Biology
Darwin's Origin, Huxley — popular-level Victorian/Edwardian science writing.
Studies of American Fungi. Mushrooms, Edible, Poisonous, etc.
Atkinson, George Francis
15,601 Gutenberg downloadsen2008Difficulty 50 (College)Vegetable Teratology An Account of the Principal Deviations from the Usual Construction of Plants
Masters, Maxwell T. (Maxwell Tylden)
12,313 Gutenberg downloadsen2007Difficulty 61 (Academic)The Elements of Bacteriological Technique A Laboratory Guide for Medical, Dental, and Technical Students. Second Edition Rewritten and Enlarged.
Eyre, J. W. H. (John William Henry)
12,051 Gutenberg downloadsen2009Difficulty 59 (Graduate)Life and Letters of Charles Darwin — Volume 1
Darwin, Charles
11,685 Gutenberg downloadsen2000Difficulty 54 (Graduate)More Letters of Charles Darwin — Volume 1 A Record of His Work in a Series of Hitherto Unpublished Letters
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11,476 Gutenberg downloadsen2001Difficulty 50 (College)On the Origin of Species By Means of Natural Selection Or, the Preservation of Favoured Races in the Struggle for Life
Darwin, Charles
11,346 Gutenberg downloadsen1998Difficulty 61 (Academic)The Variation of Animals and Plants Under Domestication, Vol. I.
Darwin, Charles
10,500 Gutenberg downloadsen2008Difficulty 67 (Academic)The Natural History of Pliny, Volume 3 (of 6)
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10,021 Gutenberg downloadsen2019Difficulty 38 (High School)Darwin, and After Darwin, Volumes 1 and 3 An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions
Romanes, George John
8,952 Gutenberg downloadsen2008Difficulty 55 (Graduate)On the Origin of Species by Means of Natural Selection or the Preservation of Favoured Races in the Struggle for Life. (2nd edition)
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8,719 Gutenberg downloadsen2007Difficulty 73 (Expert)The Notebooks of Leonardo Da Vinci — Complete
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7,998 Gutenberg downloadsen2008Difficulty 78 (Expert)Evolution, Old & New Or, the Theories of Buffon, Dr. Erasmus Darwin and Lamarck, as compared with that of Charles Darwin
Butler, Samuel
7,988 Gutenberg downloadsen2007Difficulty 57 (Graduate)Contributions to the Theory of Natural Selection A Series of Essays
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7,552 Gutenberg downloadsen2007Difficulty 63 (Academic)Cattle and Their Diseases Embracing Their History and Breeds, Crossing and Breeding, and Feeding and Management; with the Diseases to Which They Are Subject, and the Remedies Best Adapted to Their Cure
Jennings, Robert
7,482 Gutenberg downloadsen2007Difficulty 67 (Academic)Letters of Asa Gray; Vol. 2
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7,220 Gutenberg downloadsen2017Difficulty 47 (College)The Foundations of the Origin of Species Two Essays written in 1842 and 1844
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6,188 Gutenberg downloadsen2007Difficulty 56 (Graduate)Birds of the Rockies
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6,174 Gutenberg downloadsen2008Difficulty 58 (Graduate)Insects and Diseases A Popular Account of the Way in Which Insects may Spread or Cause some of our Common Diseases
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Unknown
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5,381 Gutenberg downloadsen2014Difficulty 62 (Academic)The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality
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5,278 Gutenberg downloadsen2007Difficulty 56 (Graduate)Sketches of the Natural History of Ceylon
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5,038 Gutenberg downloadsen2004Difficulty 72 (Expert)Zoölogische Philosophie Of beschouwingen over de Natuurlijke Historie der dieren etc.
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4,734 Gutenberg downloadsnl2008The Dawn of Reason; or, Mental Traits in the Lower Animals
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4,644 Gutenberg downloadsen2007Difficulty 70 (Academic)Sir Jagadis Chunder Bose, His Life and Speeches
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4,588 Gutenberg downloadsen2007Difficulty 65 (Academic)An Introduction to Entomology: Vol. 3 or Elements of the Natural History of the Insects
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4,582 Gutenberg downloadsen2013Difficulty 61 (Academic)The Stock-Feeder's Manual the chemistry of food in relation to the breeding and feeding of live stock
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4,554 Gutenberg downloadsen2008Difficulty 59 (Graduate)Outlines of Dairy Bacteriology, 8th edition A Concise Manual for the Use of Students in Dairying
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4,320 Gutenberg downloadsen2009Difficulty 62 (Academic)An Introduction to Entomology: Vol. 4 or Elements of the Natural History of the Insects
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4,297 Gutenberg downloadsen2013Difficulty 68 (Academic)The Expression of the Emotions in Man and Animals
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4,163 Gutenberg downloadsen1998Difficulty 64 (Academic)The Origin of Species by Means of Natural Selection Or, the Preservation of Favoured Races in the Struggle for Life, 6th Edition
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3,670 Gutenberg downloadsla2008Journal of Researches into the Natural History and Geology of the Countries Visited During the Voyage Round the World of H.M.S. Beagle Under the Command of Captain Fitz Roy, R.N.
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3,449 Gutenberg downloadsen2007Difficulty 51 (Graduate)Himalayan Journals — Complete Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.
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1,149 Gutenberg downloadsen2003Difficulty 60 (Graduate)Special report on diseases of cattle
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1,144 Gutenberg downloadsen2009Difficulty 53 (Graduate)An Australian Bird Book: A Pocket Book for Field Use
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1,119 Gutenberg downloadsen2014Difficulty 50 (College)A History of Science — Volume 2
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1,114 Gutenberg downloadsen1999Difficulty 63 (Academic)The Chain of Life in Geological Time A Sketch of the Origin and Succession of Animals and Plants
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1,114 Gutenberg downloadsen2011Difficulty 56 (Graduate)The History of Creation, Vol. 2 (of 2) Or the Development of the Earth and its Inhabitants by the Action of Natural Causes
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864 Gutenberg downloadsen2025Difficulty 50 (College)The Mason-Bees
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808 Gutenberg downloadsen2014Difficulty 72 (Expert)The Beaked Whales of the Family Ziphiidae An Account of the Beaked Whales of the Family Ziphiidae in the Collection of the United States Museum...
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798 Gutenberg downloadsen2009Difficulty 57 (Graduate)Memoirs of the Distinguished Men of Science of Great Britain Living in the Years 1807-8
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775 Gutenberg downloadsen2008Difficulty 63 (Academic)Lachesis Lapponica; Or, A Tour in Lapland, Volume 1
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772 Gutenberg downloadsen2012Difficulty 100 (Quantum Electrodynamics)Index of the Project Gutenberg Works of Charles Darwin
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772 Gutenberg downloadsen2019Difficulty 88 (Specialist)Domesticated animals : $b Their relation to man and to his advancement in civilization
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771 Gutenberg downloadsen2008Difficulty 63 (Academic)The Recent Mammals of Tamaulipas, México
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771 Gutenberg downloadsen2012Difficulty 57 (Graduate)A Synopsis of the North American Lagomorpha
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768 Gutenberg downloadsen2006Difficulty 53 (Graduate)Natural History of Cottonmouth Moccasin, Agkistrodon piscovorus (Reptilia)
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763 Gutenberg downloadsen2013Difficulty 59 (Graduate)The Evolution of Marriage and of the Family
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763 Gutenberg downloadsen2022Difficulty 61 (Academic)Drawings and Pharmacy in Al-Zahrawi's 10th-Century Surgical Treatise
Hamarneh, Sami Khalaf
759 Gutenberg downloadsen2008Difficulty 62 (Academic)The Botanical Magazine, Vol. 01 Or, Flower-Garden Displayed
Curtis, William
759 Gutenberg downloadsen2005Difficulty 57 (Graduate)Sea-Weeds, Shells and Fossils
Gray, Peter & Woodward, B. B. (Bernard Bolingbroke)
757 Gutenberg downloadsen2011Difficulty 58 (Graduate)Travels on the Amazon
Wallace, Alfred Russel
756 Gutenberg downloadsen2016Difficulty 65 (Academic)The Breath of Life
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754 Gutenberg downloadsen2006Difficulty 57 (Graduate)Handbook of the Trees of New England
Dame, Lorin Low & Brooks, Henry M. (Henry Mason)
752 Gutenberg downloadsen2007Difficulty 53 (Graduate)Woman and Womanhood: A Search for Principles
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752 Gutenberg downloadsen2006Difficulty 59 (Graduate)Cassell's Natural History, Vol. 3 (of 6)
Unknown
750 Gutenberg downloadsen2020Difficulty 100 (Quantum Electrodynamics)The Different Forms of Flowers on Plants of the Same Species
Darwin, Charles
749 Gutenberg downloadsen2003Difficulty 62 (Academic)The Story of Evolution
McCabe, Joseph
749 Gutenberg downloadsen1997Difficulty 56 (Graduate)British Pomology Or, the History, Description, Classification, and Synonymes, of the Fruits and Fruit Trees of Great Britain
Hogg, Robert
747 Gutenberg downloadsen2014Difficulty 58 (Graduate)Cassell's book of birds; vol. 3
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744 Gutenberg downloadsen2019Difficulty 62 (Academic)Pioneers of Evolution from Thales to Huxley With an Intermediate Chapter on the Causes of Arrest of the Movement
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743 Gutenberg downloadsen2012Difficulty 58 (Graduate)Species and Varieties, Their Origin by Mutation
Vries, Hugo de
742 Gutenberg downloadsen2005Difficulty 60 (Graduate)The Chautauquan, Vol. 05, June 1885, No. 9
Chautauqua Literary and Scientific Circle & Chautauqua Institution
741 Gutenberg downloadsen2017Difficulty 53 (Graduate)Observations of a Naturalist in the Pacific Between 1896 and 1899, Volume 2 Plant-Dispersal
Guppy, H. B. (Henry Brougham)
740 Gutenberg downloadsen2017Difficulty 59 (Graduate)The Lobster Fishery of Maine Bulletin of the United States Fish Commission, Vol. 19, Pages 241-265, 1899
Cobb, John N. (John Nathan)
740 Gutenberg downloadsen2006Difficulty 51 (Graduate)An introduction to the study of fishes
Günther, Albert C. L. G. (Albert Carl Ludwig Gotthilf)
736 Gutenberg downloadsen2023Difficulty 74 (Expert)Anatomy of the Cat
Reighard, Jacob & Jennings, H. S. (Herbert Spencer)
736 Gutenberg downloadsen2018Difficulty 52 (Graduate)Animal Behaviour
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735 Gutenberg downloadsen2017Difficulty 56 (Graduate)Louis Pasteur: His Life and Labours
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735 Gutenberg downloadsen2014Difficulty 59 (Graduate)Bodily changes in pain, hunger, fear, and rage : $b an account of recent researches into the function of emotional excitement
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734 Gutenberg downloadsen2024Difficulty 75 (Expert)Scientific American Supplement, No. 799, April 25, 1891
Various
734 Gutenberg downloadsen2004Difficulty 50 (College)The Arctic World : $b Its plants, animals, and natural phenomena. With a historical sketch of Arctic discovery, down to the British polar expedition: 1875-76.
Anonymous
734 Gutenberg downloadsen2023Difficulty 60 (Graduate)L'Afrique centrale française : $b Récit du voyage de la mission
Chevalier, Auguste & Mission Chari-Lac Tchad (1902-1904)
732 Gutenberg downloadsfr2025Philosophical transactions, Vol. L. Part I. For the year 1757. Giving some account of the present undertakings, studies, and labours, of the ingenious, in many considerable parts of the world.
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731 Gutenberg downloadsen2021Difficulty 49 (College)Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, Plates Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76, Vol. XVIII
Haeckel, Ernst
731 Gutenberg downloadsen2013Difficulty 53 (Graduate)The Barren Ground Caribou of Keewatin
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730 Gutenberg downloadsen2010Difficulty 59 (Graduate)Some Reptiles and Amphibians from Korea
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729 Gutenberg downloadsen2011Difficulty 57 (Graduate)Scientific American Supplement, No. 598, June 18, 1887
Various
727 Gutenberg downloadsen2004Difficulty 50 (College)Zoological Illustrations, Volume 1 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
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727 Gutenberg downloadsen2012Difficulty 64 (Academic)The romance of insect life : $b Interesting descriptions of the strange and curious in the insect world
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725 Gutenberg downloadsen2023Difficulty 76 (Expert)The Life-Story of Insects
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724 Gutenberg downloadsen2005Difficulty 57 (Graduate)The Effects of Cross & Self-Fertilisation in the Vegetable Kingdom
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721 Gutenberg downloadsen2023Difficulty 81 (Specialist)The Chemistry of Plant Life
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719 Gutenberg downloadsen2010Difficulty 88 (Specialist)The Cambridge natural history, Vol. 04 (of 10)
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717 Gutenberg downloadsen2023Difficulty 72 (Expert)The Homing Pigeon
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715 Gutenberg downloadsen2017Difficulty 51 (Graduate)A Monograph on the Sub-class Cirripedia (Volume 1 of 2) The Lepadidae; Or, Pedunculated Cirripedes
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714 Gutenberg downloadsen2010Difficulty 59 (Graduate)The Appendages, Anatomy, and Relationships of Trilobites
Raymond, Percy E. (Percy Edward)
713 Gutenberg downloadsen2012Difficulty 67 (Academic)André Michaux's Travels into Kentucky, 1793-96; François André Michaux's Travels West of Alleghany Mountains, 1802; Thaddeus Mason Harris's Journal of a Tour Northwest of Alleghany Mountains, 1803.
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712 Gutenberg downloadsen2025Difficulty 65 (Academic)British birds
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711 Gutenberg downloadsen2024Difficulty 67 (Academic)Elementary Botany
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710 Gutenberg downloadsen2021Difficulty 53 (Graduate)Fossil plants, Vol. 1 : $b [A text-book] for students of botany and geology
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710 Gutenberg downloadsen2022Difficulty 57 (Graduate)Cassell's book of birds; vol. 2
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708 Gutenberg downloadsen2018Difficulty 58 (Graduate)Our Common Insects A Popular Account of the Insects of Our Fields, Forests, Gardens and Houses
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706 Gutenberg downloadsen2008Difficulty 53 (Graduate)The plums of New York
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704 Gutenberg downloadsen2024Difficulty 65 (Academic)Buffon's Natural History. Volume 06 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
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703 Gutenberg downloadsen2014Difficulty 60 (Graduate)Fishing Grounds of the Gulf of Maine
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703 Gutenberg downloadsen2005Difficulty 57 (Graduate)On Molecular and Microscopic Science, Volume 2 (of 2)
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703 Gutenberg downloadsen2018Difficulty 58 (Graduate)Cave Hunting Researches on the evidence of caves respecting the early inhabitants of Europe
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699 Gutenberg downloadsen2016Difficulty 77 (Expert)Cavity-Nesting Birds of North American Forests Agriculture Handbook 511
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699 Gutenberg downloadsen2015Difficulty 64 (Academic)Vestiges of the Natural History of Creation
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699 Gutenberg downloadsen2004Difficulty 66 (Academic)Trees: A Woodland Notebook Containing Observations on Certain British and Exotic Trees
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698 Gutenberg downloadsen2012Difficulty 59 (Graduate)The Life of the Grasshopper
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697 Gutenberg downloadsen2021Difficulty 51 (Graduate)The Works of William Harvey M.D. Translated from the Latin with a life of the author
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697 Gutenberg downloadsen2019Difficulty 66 (Academic)Aphorisms and Reflections from the works of T. H. Huxley
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695 Gutenberg downloadsen2011Difficulty 59 (Graduate)New-England's rarities discovered : $b In birds, beasts, fishes, serpents, and plants of that country
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694 Gutenberg downloadsen2023Difficulty 57 (Graduate)The case against evolution
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694 Gutenberg downloadsen2022Difficulty 69 (Academic)The Tropical World Aspects of man and nature in the equatorial regions of the globe.
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694 Gutenberg downloadsen2020Difficulty 95 (Quantum Electrodynamics)The Variation of Animals and Plants under Domestication — Volume 2
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694 Gutenberg downloadsen2001Difficulty 72 (Expert)Time and Change
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693 Gutenberg downloadsen2004Difficulty 54 (Graduate)General Anatomy, Applied to Physiology and Medicine, Vol. 1 (of 3)
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690 Gutenberg downloadsen2017Difficulty 67 (Academic)Noteworthy Records of Bats From Nicaragua, with a Checklist of the Chiropteran Fauna of the Country
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690 Gutenberg downloadsen2010Difficulty 55 (Graduate)Botany for Ladies or, A Popular Introduction to the Natural System of Plants, According to the Classification of De Candolle.
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689 Gutenberg downloadsen2014Difficulty 54 (Graduate)Half hours with the lower animals : $b protozoans, sponges, corals, shells, insects, and crustaceans
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688 Gutenberg downloadsen2014Difficulty 60 (Graduate)Scientific American Supplement, No. 388, June 9, 1883
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688 Gutenberg downloadsen2005Difficulty 56 (Graduate)Scientific American Supplement, No. 520, December 19, 1885
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688 Gutenberg downloadsen2004Difficulty 56 (Graduate)The Butterfly Book A Popular Guide to a Knowledge of the Butterflies of North America
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688 Gutenberg downloadsen2012Difficulty 55 (Graduate)The Story of the Living Machine A Review of the Conclusions of Modern Biology in Regard to the Mechanism Which Controls the Phenomena of Living Activity
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688 Gutenberg downloadsen2005Difficulty 58 (Graduate)The Taleef Shereef; Or, Indian Materia Medica
Unknown
688 Gutenberg downloadsen2016Difficulty 54 (Graduate)The Pleistocene of North America and its vertebrated animals from the states east of the Mississippi River and from the Canadian provinces east of longitude 95°
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687 Gutenberg downloadsen2020Difficulty 73 (Expert)The Variation of Animals and Plants under Domestication — Volume 1
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687 Gutenberg downloadsen2001Difficulty 62 (Academic)Essays: Scientific, Political, & Speculative; Vol. 1 of 3 Library Edition (1891), Containing Seven Essays not before Republished, and Various other Additions.
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684 Gutenberg downloadsen2009Difficulty 67 (Academic)Text Book of Biology, Part 1: Vertebrata
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683 Gutenberg downloadsen2007Difficulty 61 (Academic)The Making of Species
Dewar, Douglas & Finn, Frank
682 Gutenberg downloadsen2013Difficulty 72 (Expert)Chambers's Elementary Science Readers Book I
Various
681 Gutenberg downloadsen2006Difficulty 27 (Middle School)The apiary; or, bees, bee-hives, and bee culture [1878] being a familiar account of the habits of bees, and the most improved methods of management
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681 Gutenberg downloadsen2022Difficulty 53 (Graduate)Dinosaurs, with Special Reference to the American Museum Collections
Matthew, William Diller
680 Gutenberg downloadsen2006Difficulty 59 (Graduate)Science in Arcady
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680 Gutenberg downloadsen2005Difficulty 63 (Academic)Versuche über Pflanzenhybriden
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679 Gutenberg downloadsde2012Structure and Functions of the Body A Hand-Book of Anatomy and Physiology for Nurses and Others Desiring a Practical Knowledge of the Subject
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677 Gutenberg downloadsen2021Difficulty 66 (Academic)Homo-Culture; Or, The Improvement of Offspring Through Wiser Generation
Holbrook, M. L. (Martin Luther)
676 Gutenberg downloadsen2010Difficulty 66 (Academic)Every Girl's Book
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673 Gutenberg downloadsen2009Difficulty 41 (College)Intelligence in Plants and Animals Being a New Edition of the Author's Privately Issued "Soul and Immortality."
Gentry, Thomas G. (Thomas George)
671 Gutenberg downloadsen2021Difficulty 71 (Expert)Lehrbuch der Botanik für Hochschulen
Strasburger, Eduard & Noll, Fritz & Schenck, H. (Heinrich) & Schimper, A. F. W. (Andreas Franz Wilhelm)
670 Gutenberg downloadsde2020Recuerdos de mi vida (tomo 2 de 2)
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669 Gutenberg downloadses2019A handbook of systematic botany
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667 Gutenberg downloadsen2022Difficulty 55 (Graduate)Glimpses of Ocean Life; Or, Rock-Pools and the Lessons they Teach
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666 Gutenberg downloadsen2016Difficulty 66 (Academic)Man's Place in the Universe A Study of the Results of Scientific Research in Relation to the Unity or Plurality of Worlds, 3rd Edition
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666 Gutenberg downloadsen2012Difficulty 71 (Expert)Le monde de la mer
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665 Gutenberg downloadsfr2023Synopsis of Some Genera of the Large Pyrenomycetes Camillea, Thamnomyces, Engleromyces
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665 Gutenberg downloadsen2007Difficulty 52 (Graduate)The Snakes of Europe
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664 Gutenberg downloadsen2014Difficulty 63 (Academic)A Hand-book to the Primates, Volume 2 (of 2)
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662 Gutenberg downloadsen2013Difficulty 54 (Graduate)Studies in the Theory of Descent, Volume II
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662 Gutenberg downloadsen2015Difficulty 65 (Academic)The Butterflies of the British Isles
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661 Gutenberg downloadsen2013Difficulty 57 (Graduate)The life of Pasteur
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661 Gutenberg downloadsen2019Difficulty 59 (Graduate)The Mechanism of Life
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659 Gutenberg downloadsen2010Difficulty 63 (Academic)Vertebrates from the Barrier Island of Tamaulipas, México
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658 Gutenberg downloadsen2011Difficulty 54 (Graduate)The Nests and Eggs of Indian Birds, Volume 1
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657 Gutenberg downloadsen2004Difficulty 49 (College)An Experimental Translocation of the Eastern Timber Wolf
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656 Gutenberg downloadsen2011Difficulty 56 (Graduate)Elements of Physiophilosophy
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655 Gutenberg downloadsen2015Difficulty 61 (Academic)Scientific American Supplement, No. 561, October 2, 1886
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654 Gutenberg downloadsen2005Difficulty 50 (College)Darwiniana : Essays — Volume 02
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653 Gutenberg downloadsen2004Difficulty 68 (Academic)The Lights of the Church and the Light of Science Essay #6 from "Science and Hebrew Tradition"
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650 Gutenberg downloadsen2001Difficulty 70 (Academic)On the mode of communication of cholera
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649 Gutenberg downloadsen2024Difficulty 58 (Graduate)Scientific American Supplement, No. 711, August 17, 1889
Various
649 Gutenberg downloadsen2005Difficulty 61 (Academic)Antarctic Penguins: A Study of Their Social Habits
Levick, G. Murray (George Murray)
648 Gutenberg downloadsen2011Difficulty 50 (College)Cassell's book of birds; vol. 1
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648 Gutenberg downloadsen2015Difficulty 61 (Academic)The Coming of Evolution: The Story of a Great Revolution in Science
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648 Gutenberg downloadsen2010Difficulty 68 (Academic)The Glands Regulating Personality A Study of the Glands of Internal Secretion in Relation to the Types of Human Nature
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647 Gutenberg downloadsen2003Difficulty 58 (Graduate)The Brain and the Voice in Speech and Song
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646 Gutenberg downloadsen2004Difficulty 68 (Academic)The World's Greatest Books — Volume 15 — Science
Unknown
646 Gutenberg downloadsen2008Difficulty 67 (Academic)Illustrations of Exotic Entomology, Volume 1
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645 Gutenberg downloadsen2014Difficulty 62 (Academic)Insect life: Souvenirs of a naturalist
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645 Gutenberg downloadsen2022Difficulty 51 (Graduate)Noteworthy families (modern science) : $b An index to kinships in near degrees between persons whose achievements are honourable, and have been publicly recorded
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645 Gutenberg downloadsen2005Difficulty 64 (Academic)On the Relations of Man to the Lower Animals
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645 Gutenberg downloadsen2001Difficulty 72 (Expert)Scientific American Supplement, No. 492, June 6, 1885
Various
644 Gutenberg downloadsen2004Difficulty 53 (Graduate)Flora von Deutschland Ein Hilfsbuch zum Bestimmen der zwischen den deutschen Meeren und den Alpen wildwachsenden und angebauten Pflanzen
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643 Gutenberg downloadsde2019The Life of the Caterpillar
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643 Gutenberg downloadsen2021Difficulty 51 (Graduate)Living lights : $b A popular account of phosphorescent animals and vegetables
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642 Gutenberg downloadsen2025Difficulty 58 (Graduate)The Chautauquan, Vol. 05, April 1885
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642 Gutenberg downloadsen2017Difficulty 54 (Graduate)Useful Knowledge: Volume 2. Vegetables Or, a familiar account of the various productions of nature
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642 Gutenberg downloadsen2018Difficulty 51 (Graduate)Life History and Ecology of the Five-Lined Skink, Eumeces fasciatus
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641 Gutenberg downloadsen2012Difficulty 62 (Academic)American Addresses, with a Lecture on the Study of Biology
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640 Gutenberg downloadsen2005Difficulty 67 (Academic)Appletons' Popular Science Monthly, April 1899 Volume LIV, No. 6, April 1899
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638 Gutenberg downloadsen2013Difficulty 56 (Graduate)The Popular Science Monthly, October, 1900 Vol. 57, May, 1900 to October, 1900
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638 Gutenberg downloadsen2014Difficulty 75 (Expert)First course in biology
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637 Gutenberg downloadsen2025Difficulty 46 (College)Scientific American Supplement No. 822, October 3, 1891
Various
636 Gutenberg downloadsen2005Difficulty 55 (Graduate)A Guide for the Study of Animals
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634 Gutenberg downloadsen2011Difficulty 48 (College)Dactylography; Or, The Study of Finger-prints
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634 Gutenberg downloadsen2015Difficulty 59 (Graduate)North American Jumping Mice (Genus Zapus)
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633 Gutenberg downloadsen2012Difficulty 64 (Academic)Secrets of Earth and Sea
Lankester, E. Ray (Edwin Ray), Sir
633 Gutenberg downloadsen2016Difficulty 53 (Graduate)The book of antelopes, vol. 1 (of 4)
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631 Gutenberg downloadsen2023Difficulty 49 (College)The Meaning of Evolution
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630 Gutenberg downloadsen2009Difficulty 51 (Graduate)Charles Darwin
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628 Gutenberg downloadsen2010Difficulty 73 (Expert)Species Plantarum, Sections I-III
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628 Gutenberg downloadsla2007Scientific American Supplement, No. 795, March 28, 1891
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627 Gutenberg downloadsen2004Difficulty 62 (Academic)The physiology of digestion considered with relation to the principles of dietetics
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625 Gutenberg downloadsen2023Difficulty 83 (Specialist)Creierul, O Enigma Descifrata
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624 Gutenberg downloadsro2004Appletons' Popular Science Monthly, March 1899 Volume LIV, No. 5, March 1899
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623 Gutenberg downloadsen2013Difficulty 57 (Graduate)On the Origin and Metamorphoses of Insects
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622 Gutenberg downloadsen2011Difficulty 54 (Graduate)The Interpreters of Genesis and the Interpreters of Nature Essay #4 from "Science and Hebrew Tradition"
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621 Gutenberg downloadsen2001Difficulty 65 (Academic)Whale hunting with gun and camera A naturalist's account of the modern shore-whaling industry, of whales and their habits, and of hunting experiences in various parts of the world
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621 Gutenberg downloadsen2022Difficulty 87 (Specialist)The Romance of the Microscope An interesting description of its uses in all branches of science, industry, agriculture, and in the detection of crime, with a short account of its origin, history, and development
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620 Gutenberg downloadsen2015Difficulty 55 (Graduate)De Canibus Britannicis: Of Englishe Dogges
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619 Gutenberg downloadsen2008Difficulty 81 (Specialist)The Origin of Species From 'The Westminster Review', April 1860
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619 Gutenberg downloadsen2001Difficulty 74 (Expert)A Synopsis of the Birds of North America
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618 Gutenberg downloadsen2013Difficulty 50 (College)Scientific American Supplement, No. 433, April 19, 1884
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618 Gutenberg downloadsen2005Difficulty 66 (Academic)Seaside Studies in Natural History. Marine Animals of Massachusetts Bay. Radiates.
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618 Gutenberg downloadsen2011Difficulty 52 (Graduate)Wood and Forest
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618 Gutenberg downloadsen2011Difficulty 51 (Graduate)The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee
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617 Gutenberg downloadsen2012Difficulty 60 (Graduate)Histology of medicinal plants
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616 Gutenberg downloadsen2021Difficulty 70 (Academic)Natural Wonders
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616 Gutenberg downloadsen2015Difficulty 40 (High School)Scientific American Supplement, No. 363, December 16, 1882
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615 Gutenberg downloadsen2005Difficulty 62 (Academic)Seed Dispersal
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615 Gutenberg downloadsen2008Difficulty 46 (College)Scientific American Supplement, No. 810, July 11, 1891
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614 Gutenberg downloadsen2005Difficulty 51 (Graduate)Mendelism Third Edition
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613 Gutenberg downloadsen2009Difficulty 61 (Academic)Through Magic Glasses and Other Lectures A Sequel to The Fairyland of Science
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613 Gutenberg downloadsen2011Difficulty 58 (Graduate)British Bees An Introduction into the Studies of the Natural History and Economy of the Bees Indigenous to the British Isles
Shuckard, William Edward
612 Gutenberg downloadsen2017Difficulty 72 (Expert)Introduction à l'étude de la médecine expérimentale
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612 Gutenberg downloadsfr2005L'Académie des sciences et les académiciens de 1666 à 1793
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611 Gutenberg downloadsfr2016The Present Condition of Organic Nature Lecture I. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
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610 Gutenberg downloadsen2001Difficulty 64 (Academic)Animal intelligence: Experimental studies
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609 Gutenberg downloadsen2023Difficulty 65 (Academic)Life History of the Kangaroo Rat
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609 Gutenberg downloadsen2006Difficulty 62 (Academic)Ancient Plants Being a Simple Account of the past Vegetation of the Earth and of the Recent Important Discoveries Made in This Realm of Nature
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608 Gutenberg downloadsen2013Difficulty 57 (Graduate)Het Leven der Dieren: Deel 2, Hoofdstuk 04: De Hoendervogels
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608 Gutenberg downloadsnl2009On Some Fossil Remains of Man
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608 Gutenberg downloadsen2001Difficulty 60 (Graduate)The Evolution of Man Scientifically Disproved in 50 Arguments
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608 Gutenberg downloadsen2005Difficulty 55 (Graduate)The Biology, Physiology and Sociology of Reproduction Also Sexual Hygiene with Special Reference to the Male
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607 Gutenberg downloadsen2008Difficulty 56 (Graduate)Personality of plants
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605 Gutenberg downloadsen2022Difficulty 54 (Graduate)Animal Parasites and Messmates
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602 Gutenberg downloadsen2015Difficulty 57 (Graduate)The Fantastic Clan: The Cactus Family
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602 Gutenberg downloadsen2014Difficulty 67 (Academic)Aspects of nature, in different lands and different climates (Vol. 2 of 2) with scientific elucidations
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601 Gutenberg downloadsen2022Difficulty 72 (Expert)Life of Elie Metchnikoff, 1845-1916
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601 Gutenberg downloadsen2013Difficulty 66 (Academic)Grundriß der menschlichen Erblichkeitslehre und Rassenhygiene (1/2) Menschliche Erblichkeitslehre
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600 Gutenberg downloadsde2015Ideen zu einer Physiognomik der Gewächse
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600 Gutenberg downloadsde2007Initiative in Evolution
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600 Gutenberg downloadsen2016Difficulty 57 (Graduate)Thoughts on Religion
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600 Gutenberg downloadsen2005Difficulty 72 (Expert)The Bird Study Book
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599 Gutenberg downloadsen2007Difficulty 52 (Graduate)An essay towards a natural history of serpents
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598 Gutenberg downloadsen2023Difficulty 49 (College)Natural History of the Ornate Box Turtle, Terrapene ornata ornata Agassiz
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598 Gutenberg downloadsen2011Difficulty 63 (Academic)Life Movements in Plants, Volume II
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597 Gutenberg downloadsen2012Difficulty 73 (Expert)Little Masterpieces of Science: The Naturalist as Interpreter and Seer
Unknown
597 Gutenberg downloadsen2009Difficulty 63 (Academic)On the Advisableness of Improving Natural Knowledge
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596 Gutenberg downloadsen2001Difficulty 72 (Expert)Criticisms on "The Origin of Species" From 'The Natural History Review', 1864
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595 Gutenberg downloadsen2001Difficulty 64 (Academic)Hints towards the formation of a more comprehensive theory of life.
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595 Gutenberg downloadsen2008Difficulty 68 (Academic)Scientific American Supplement, No. 601, July 9, 1887
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594 Gutenberg downloadsen2004Difficulty 53 (Graduate)Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, II. Band Von Galilei bis zur Mitte des XVIII. Jahrhunderts
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593 Gutenberg downloadsde2017Facts and Arguments for Darwin
Müller, Fritz
593 Gutenberg downloadsen2004Difficulty 70 (Academic)Philosophical transactions, Vol. L. Part II. For the year 1758. Giving some account of the present undertakings, studies, and labours, of the ingenious, in many considerable parts of the world.
Various & Royal Society (Great Britain)
593 Gutenberg downloadsen2022Difficulty 49 (College)Physics and Politics, or, Thoughts on the application of the principles of "natural selection" and "inheritance" to political society
Bagehot, Walter
593 Gutenberg downloadsen2003Difficulty 64 (Academic)The Life of an Insect being a history of the changes of insects from the egg to the perfect being.
Unknown
593 Gutenberg downloadsen2014Difficulty 62 (Academic)Life: Its True Genesis
Flaccus, Horatius
592 Gutenberg downloadsen2005Difficulty 60 (Graduate)Disease and Its Causes
Councilman, W. T. (William Thomas)
591 Gutenberg downloadsen2005Difficulty 57 (Graduate)Subspeciation in the Kangaroo Rat, Dipodomys ordii KU. Vol 1 No 23
Setzer, Henry W.
591 Gutenberg downloadsen2013Difficulty 66 (Academic)The Evolution Theory, Vol. 2 of 2
Weismann, August
591 Gutenberg downloadsen2021Difficulty 64 (Academic)Abstracts of Papers Read at the First International Eugenics Congress University of London, July, 1912
International Eugenics Congress (1st : 1912 : London)
590 Gutenberg downloadsen2014Difficulty 65 (Academic)Les abeilles
Pérez, Jean M.
590 Gutenberg downloadsfr2011North American Yellow Bats, 'Dasypterus,' and a List of the Named Kinds of the Genus Lasiurus Gray
Hall, E. Raymond (Eugene Raymond) & Jones, J. Knox
589 Gutenberg downloadsen2010Difficulty 59 (Graduate)Outlines of Lessons in Botany, Part I; from Seed to Leaf For the Use of Teachers, or Mothers Studying with Their Children
Moore, Jane Newell
588 Gutenberg downloadsen2004Difficulty 42 (College)Über die Entstehung der Arten im Thier- und Pflanzen-Reich durch natürliche Züchtung
Darwin, Charles
588 Gutenberg downloadsde2022The Rise and Progress of Palaeontology Essay #2 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
587 Gutenberg downloadsen2001Difficulty 77 (Expert)Outlines of Creation
Noyce, Elisha
586 Gutenberg downloadsen2015Difficulty 68 (Academic)The Botanist's Companion, Volume II Or an Introduction to the Knowledge of Practical Botany, and the Uses of Plants. Either Growing Wild in Great Britain, or Cultivated for the Puroses of Agriculture, Medicine, Rural Oeconomy, or the Arts
Salisbury, William
586 Gutenberg downloadsen2004Difficulty 55 (Graduate)Popular Books on Natural Science For Practical Use in Every Household, for Readers of All Classes
Bernstein, Aaron David
584 Gutenberg downloadsen2011Difficulty 50 (College)Speciation in the Brazilian Spiny Rats
Moojen, João
584 Gutenberg downloadsen2013Difficulty 70 (Academic)Studies on Fermentation The diseases of beer, their causes, and the means of preventing them
Pasteur, Louis
584 Gutenberg downloadsen2020Difficulty 55 (Graduate)An Introduction to Nature-study
Stenhouse, E. (Ernest)
583 Gutenberg downloadsen2020Difficulty 42 (College)Appletons' Popular Science Monthly, July 1899 Volume LV, No. 3, July 1899
Various
583 Gutenberg downloadsen2014Difficulty 58 (Graduate)The Genetic Effects of Radiation
Asimov, Isaac & Dobzhansky, Theodosius
583 Gutenberg downloadsen2017Difficulty 59 (Graduate)Creation and Its Records A Brief Statement of Christian Belief with Reference to Modern Facts and Ancient Scripture
Baden-Powell, B. H. (Baden Henry)
582 Gutenberg downloadsen2004Difficulty 62 (Academic)Het Leven der Dieren. Deel 3. Afdeling 2. De Visschen
Brehm, Alfred Edmund
582 Gutenberg downloadsnl2016A treatise on the esculent funguses of England containing an account of their classical history, uses, characters, development, structure, nutritious properties, modes of cooking and preserving, etc.
Badham, David
581 Gutenberg downloadsen2019Difficulty 68 (Academic)Natural History of the Racer Coluber constrictor
Fitch, Henry S. (Henry Sheldon)
581 Gutenberg downloadsen2013Difficulty 69 (Academic)The Courtship of Animals
Pycraft, W. P. (William Plane)
581 Gutenberg downloadsen2019Difficulty 66 (Academic)Mammals of the Southwest Mountains and Mesas
Olin, George
580 Gutenberg downloadsen2016Difficulty 57 (Graduate)Life Movements in Plants, Volume I
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579 Gutenberg downloadsen2015Difficulty 69 (Academic)Scientific American Supplement, No. 417, December 29, 1883
Various
579 Gutenberg downloadsen2005Difficulty 65 (Academic)Scientific American Supplement, No. 299, September 24, 1881
Various
578 Gutenberg downloadsen2005Difficulty 60 (Graduate)The birds of Jamaica
Gosse, Philip Henry
578 Gutenberg downloadsen2024Difficulty 63 (Academic)The Principles of Breeding or, Glimpses at the Physiological Laws involved in the Reproduction and Improvement of Domestic Animals
Goodale, S. L. (Stephen Lincoln)
577 Gutenberg downloadsen2007Difficulty 57 (Graduate)Birds, Illustrated by Color Photography, Vol. 1, No. 6 June, 1897
Various
575 Gutenberg downloadsen2009Difficulty 48 (College)The Popular Science Monthly, September, 1900 Vol. 57, May, 1900 to October, 1900
Various
575 Gutenberg downloadsen2014Difficulty 77 (Expert)Our Summer Migrants An Account of the Migratory Birds Which Pass the Summer in the British Islands.
Harting, James Edmund
572 Gutenberg downloadsen2019Difficulty 57 (Graduate)The Botanical Magazine, Vol. 07 Or, Flower-Garden Displayed
Curtis, William
572 Gutenberg downloadsen2007Difficulty 58 (Graduate)The Edinburgh New Philosophical Journal, Vol. XLIX April-October 1850
Various
572 Gutenberg downloadsen2013Difficulty 66 (Academic)The Foot-prints of the Creator : $b or, The Asterolepis of Stromness
Miller, Hugh
572 Gutenberg downloadsen2022Difficulty 66 (Academic)Animal Locomotion; or, walking, swimming, and flying With a dissertation on aëronautics
Pettigrew, James Bell
571 Gutenberg downloadsen2018Difficulty 66 (Academic)Scientific American Supplement, No. 315, January 14, 1882
Various
571 Gutenberg downloadsen2006Difficulty 63 (Academic)Forest Trees of Illinois: How to Know Them
Fuller, George D. (George Damon) & Mattoon, Wilbur R. (Wilbur Reed) & Miller, Robert B. (Robert Barclay) & Nuuttila, E. E.
570 Gutenberg downloadsen2011Difficulty 50 (College)Canterbury Pieces
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569 Gutenberg downloadsen2002Difficulty 55 (Graduate)European Fungus Flora: Agaricaceae
Massee, George
569 Gutenberg downloadsen2010Difficulty 48 (College)Text book of veterinary medicine, Volume 4 (of 5)
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568 Gutenberg downloadsen2024Difficulty 69 (Academic)The Honey-Bee: Its Natural History, Physiology and Management
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568 Gutenberg downloadsen2022Difficulty 63 (Academic)Warum wir sterben
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568 Gutenberg downloadsde2008Mr. Gladstone and Genesis Essay #5 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
566 Gutenberg downloadsen2001Difficulty 59 (Graduate)Research methods in ecology
Clements, Frederic E. (Frederic Edward)
566 Gutenberg downloadsen2024Difficulty 50 (College)Scientific American Supplement, No. 829, November 21, 1891
Various
566 Gutenberg downloadsen2005Difficulty 63 (Academic)The Geographical Distribution of Animals, Volume 2 With a study of the relations of living and extinct faunas as elucidating the past changes of the Earth's surface
Wallace, Alfred Russel
566 Gutenberg downloadsen2018Difficulty 64 (Academic)De l'origine des espèces
Darwin, Charles
565 Gutenberg downloadsfr2004Scientific American Supplement, No. 324, March 18, 1882
Various
565 Gutenberg downloadsen2005Difficulty 53 (Graduate)Within the Deep Cassell's "Eyes and No Eyes" Series, Book VIII.
Smith, R. Cadwallader
565 Gutenberg downloadsen2004Difficulty 34 (High School)A Critical Examination of the Position of Mr. Darwin's Work, "On the Origin of Species," in Relation to the Complete Theory of the Causes of the Phenomena of Organic Nature Lecture VI. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
564 Gutenberg downloadsen2001Difficulty 67 (Academic)Die epiphytische Vegetation Amerikas
Schimper, A. F. W. (Andreas Franz Wilhelm)
563 Gutenberg downloadsde2007Nature readers : $b Sea-side and way-side. No. 4
Wright, Julia McNair
563 Gutenberg downloadsen2023Difficulty 45 (College)On the Study of Zoology
Huxley, Thomas Henry
563 Gutenberg downloadsen2001Difficulty 66 (Academic)The Dinosaur Quarry. Dinosaur National Monument, Colorado-Utah
Good, John M. (John Maxwell) & Stucker, Gilbert F. & White, Theodore Elmer
563 Gutenberg downloadsen2015Difficulty 54 (Graduate)Birds of Guernsey (1879) And the Neighbouring Islands: Alderney, Sark, Jethou, Herm; Being a Small Contribution to the Ornitholony of the Channel Islands
Smith, Cecil
562 Gutenberg downloadsen2004Difficulty 65 (Academic)Journal of a tour in Marocco and the Great Atlas
Hooker, Joseph Dalton & Ball, John
562 Gutenberg downloadsen2023Difficulty 66 (Academic)Scientific American Supplement, No. 595, May 28, 1887
Various
562 Gutenberg downloadsen2004Difficulty 52 (Graduate)The Life and Love of the Insect
Fabre, Jean-Henri
562 Gutenberg downloadsen2022Difficulty 50 (College)Buffon's Natural History, Volume 01 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Mineral, &c. &c
Buffon, Georges Louis Leclerc, comte de
561 Gutenberg downloadsen2014Difficulty 76 (Expert)Nouveaux souvenirs entomologiques - Livre II Étude sur l'instinct et les moeurs des insectes
Fabre, Jean-Henri
561 Gutenberg downloadsfr2006Scientific American Supplement, No. 303, October 22, 1881
Various
561 Gutenberg downloadsen2005Difficulty 52 (Graduate)The Natural Philosophy of Love
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561 Gutenberg downloadsen2014Difficulty 56 (Graduate)A Historical Account of Useful Inventions and Scientific Discoveries Being a manual of instruction and entertainment.
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560 Gutenberg downloadsen2016Difficulty 62 (Academic)Scientific American Supplement, No. 358, November 11, 1882
Various
560 Gutenberg downloadsen2005Difficulty 61 (Academic)Outlines of dairy bacteriology, 10th edition A concise manual for the use of students in dairying
Russell, H. L. (Harry Luman) & Hastings, E. G. (Edwin George)
559 Gutenberg downloadsen2010Difficulty 60 (Graduate)Scientific American Supplement, No. 441, June 14, 1884.
Various
559 Gutenberg downloadsen2005Difficulty 56 (Graduate)On the Reception of the 'Origin of Species'
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558 Gutenberg downloadsen2000Difficulty 66 (Academic)The Botanical Magazine, Vol. 05 Or, Flower-Garden Displayed
Curtis, William
557 Gutenberg downloadsen2006Difficulty 57 (Graduate)A Critique of the Theory of Evolution
Morgan, Thomas Hunt
556 Gutenberg downloadsen2009Difficulty 57 (Graduate)British Butterflies: Figures and Descriptions of Every Native Species
Coleman, W. S. (William Stephen)
556 Gutenberg downloadsen2010Difficulty 65 (Academic)The Adductor Muscles of the Jaw In Some Primitive Reptiles
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556 Gutenberg downloadsen2009Difficulty 66 (Academic)The Life of the Scorpion
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556 Gutenberg downloadsen2021Difficulty 49 (College)Harvey's Views on the Use of the Circulation of the Blood
Curtis, John Green
555 Gutenberg downloadsen2014Difficulty 69 (Academic)Mental Radio
Sinclair, Upton
555 Gutenberg downloadsen2020Difficulty 52 (Graduate)Scientific American Supplement, No. 455, September 20, 1884
Various
554 Gutenberg downloadsen2004Difficulty 57 (Graduate)History of Embalming and of Preparations in Anatomy, Pathology, and Natural History; Including an Account of a New Process for Embalming
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553 Gutenberg downloadsen2015Difficulty 78 (Expert)Biology and Its Makers With Portraits and Other Illustrations
Locy, William A. (William Albert)
552 Gutenberg downloadsen2019Difficulty 56 (Graduate)The Social Direction of Evolution: An Outline of the Science of Eugenics
Kellicott, William E. (William Erskine)
552 Gutenberg downloadsen2010Difficulty 63 (Academic)Scientific American Supplement, No. 643, April 28, 1888
Various
551 Gutenberg downloadsen2005Difficulty 65 (Academic)Scientific American Supplement, No. 385, May 19, 1883
Various
548 Gutenberg downloadsen2005Difficulty 58 (Graduate)The botanist's repository for new and rare plants; vol. 01 & 02 [of 10]
Andrews, Henry Cranke, active 1799-1828
547 Gutenberg downloadsen2023Difficulty 57 (Graduate)Histology of the Blood, Normal and Pathological
Ehrlich, Paul & Lazarus, Adolf
546 Gutenberg downloadsen2009Difficulty 63 (Academic)The Pecan and its Culture
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546 Gutenberg downloadsen2009Difficulty 57 (Graduate)Scientific American Supplement, No. 613, October 1, 1887
Various
545 Gutenberg downloadsen2005Difficulty 63 (Academic)The Last Link: Our Present Knowledge of the Descent of Man
Haeckel, Ernst
545 Gutenberg downloadsen2013Difficulty 63 (Academic)Appletons' Popular Science Monthly, November 1898 Volume 54, November 1898
Various
544 Gutenberg downloadsen2013Difficulty 60 (Graduate)Darwiniana; Essays and Reviews Pertaining to Darwinism
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544 Gutenberg downloadsen2004Difficulty 69 (Academic)History of biology
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544 Gutenberg downloadsen2018Difficulty 61 (Academic)Haeckel : $b his life and work
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543 Gutenberg downloadsen2023Difficulty 53 (Graduate)The History of Insects
Unknown
543 Gutenberg downloadsen2004Difficulty 55 (Graduate)The Past Condition of Organic Nature Lecture II. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
543 Gutenberg downloadsen2001Difficulty 65 (Academic)Appletons' Popular Science Monthly, February 1900 Vol. 56, November, 1899 to April, 1900
Various
542 Gutenberg downloadsen2014Difficulty 62 (Academic)A Review of the Middle American Tree Frogs of the Genus Ptychohyla
Duellman, William Edward
541 Gutenberg downloadsen2011Difficulty 58 (Graduate)Summer Birds From the Yucatan Peninsula, Mexico
Klaas, Erwin E.
541 Gutenberg downloadsen2011Difficulty 52 (Graduate)The human species
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541 Gutenberg downloadsen2023Difficulty 56 (Graduate)Himalayan Journals — Volume 1 Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.
Hooker, Joseph Dalton
539 Gutenberg downloadsen2004Difficulty 74 (Expert)On the Method of Zadig Essay #1 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
539 Gutenberg downloadsen2001Difficulty 66 (Academic)The Conditions of Existence as Affecting the Perpetuation of Living Beings Lecture V. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
539 Gutenberg downloadsen2001Difficulty 64 (Academic)The Lives of Celebrated Travellers, Vol. 2 (of 3)
St. John, James Augustus
539 Gutenberg downloadsen2021Difficulty 90 (Specialist)Yeast
Huxley, Thomas Henry
539 Gutenberg downloadsen2001Difficulty 66 (Academic)A Treatise on Physiology and Hygiene For Educational Institutions and General Readers
Hutchison, Joseph C. (Joseph Chrisman)
537 Gutenberg downloadsen2010Difficulty 53 (Graduate)On the Seashore Cassell's "Eyes and No Eyes" Series, Book VII
Smith, R. Cadwallader
537 Gutenberg downloadsen2003Difficulty 35 (High School)The Monist, Vol. 1, 1890-1891 : $b A quarterly magazine
Various
537 Gutenberg downloadsen2018Difficulty 64 (Academic)Charles Darwin and the Theory of Natural Selection
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536 Gutenberg downloadsen2021Difficulty 60 (Graduate)Lectures on Evolution Essay #3 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
536 Gutenberg downloadsen2001Difficulty 69 (Academic)Natural Philosophy
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536 Gutenberg downloadsen2013Difficulty 60 (Graduate)Rede, gehalten bei der Eröffnung der Versammlung deutscher Naturforscher und Ärzte in Berlin, am 18. September 1828
Humboldt, Alexander von
536 Gutenberg downloadsde2007The anatomy of the domestic fowl
Kaupp, B. F. (Benjamin Franklyn)
536 Gutenberg downloadsen2023Difficulty 65 (Academic)The Elements of Agriculture A Book for Young Farmers, with Questions Prepared for the Use of Schools
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536 Gutenberg downloadsen2010Difficulty 53 (Graduate)An elementary manual of New Zealand entomology : $b being an introduction to the study of our native insects
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535 Gutenberg downloadsen2013Difficulty 54 (Graduate)Field, Forest and Farm Things interesting to young nature-lovers, including some matters of moment to gardeners and fruit-growers
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535 Gutenberg downloadsen2022Difficulty 54 (Graduate)From an Easy Chair
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535 Gutenberg downloadsen2020Difficulty 50 (College)New observations on the natural history of bees
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535 Gutenberg downloadsen2008Difficulty 57 (Graduate)Scientific American Supplement, No. 275, April 9, 1881
Various
535 Gutenberg downloadsen2005Difficulty 57 (Graduate)Mammals of Northwestern South Dakota
Andersen, Kenneth W. & Jones, J. Knox
534 Gutenberg downloadsen2010Difficulty 50 (College)An anatomical disquisition on the motion of the heart & blood in animals
Harvey, William
533 Gutenberg downloadsen2022Difficulty 62 (Academic)Appletons' Popular Science Monthly, January 1899 Volume LIV, No. 3, January 1899
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532 Gutenberg downloadsen2013Difficulty 56 (Graduate)Essays in Natural History and Agriculture
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532 Gutenberg downloadsen2006Difficulty 64 (Academic)The Botanical Magazine, Vol. 02 Or, Flower-Garden Displayed
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532 Gutenberg downloadsen2006Difficulty 57 (Graduate)The Principles of Biology, Volume 2 (of 2)
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532 Gutenberg downloadsen2022Difficulty 63 (Academic)Grundzüge der Paläontologie (Paläozoologie). 2. Abteilung: Vertebrata.
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531 Gutenberg downloadsde2025The Method by Which the Causes of the Present and Past Conditions of Organic Nature Are to Be Discovered; the Origination of Living Beings Lecture III. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
531 Gutenberg downloadsen2001Difficulty 61 (Academic)The Principal Species of Wood: Their Characteristic Properties First Edition
Snow, Charles H. (Charles Henry)
531 Gutenberg downloadsen2014Difficulty 60 (Graduate)Was Man Created?
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531 Gutenberg downloadsen2009Difficulty 66 (Academic)Geological Contemporaneity and Persistent Types of Life
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530 Gutenberg downloadsen2001Difficulty 72 (Expert)Middle American Frogs of the Hyla microcephala Group
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529 Gutenberg downloadsen2010Difficulty 66 (Academic)Physiology
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529 Gutenberg downloadsen2016Difficulty 39 (High School)Scientific American Supplement, No. 787, January 31, 1891
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528 Gutenberg downloadsen2004Difficulty 53 (Graduate)The Mental Life of Monkeys and Apes: A Study of Ideational Behavior
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528 Gutenberg downloadsen2004Difficulty 61 (Academic)The Physical Basis of Mind Being the Second Series of Problems of Life and Mind.
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528 Gutenberg downloadsen2019Difficulty 70 (Academic)Flowers of mountain and plain
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527 Gutenberg downloadsen2014Difficulty 50 (College)The book of antelopes, vol. 3 (of 4)
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527 Gutenberg downloadsen2023Difficulty 45 (College)Wild Animals of North America Intimate Studies of Big and Little Creatures of the Mammal Kingdom
Nelson, Edward William
527 Gutenberg downloadsen2019Difficulty 52 (Graduate)De afstamming van den mensch en de seksueele teeltkeus, deel 1 (van 2)
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526 Gutenberg downloadsnl2022The Illustrated Self-Instructor in Phrenology and Physiology
Fowler, O. S. (Orson Squire) & Fowler, L. N. (Lorenzo Niles)
526 Gutenberg downloadsen2010Difficulty 64 (Academic)Essays of a Biologist
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525 Gutenberg downloadsen2021Difficulty 66 (Academic)On Snake-Poison: Its Action and Its Antidote
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525 Gutenberg downloadsen2010Difficulty 69 (Academic)Parallel Paths: A Study in Biology, Ethics, and Art
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524 Gutenberg downloadsen2014Difficulty 69 (Academic)Μικρά Φυσικά, Τόμος Πρώτος
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524 Gutenberg downloadsel2009The flowering plants of South Africa; vol. 3
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523 Gutenberg downloadsen2021Difficulty 52 (Graduate)Pearls & Parasites
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522 Gutenberg downloadsen2016Difficulty 55 (Graduate)The Migration of Birds
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522 Gutenberg downloadsen2013Difficulty 67 (Academic)Darwin
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521 Gutenberg downloadsen2023Difficulty 60 (Graduate)On the cattle plague: or, Contagious typhus in horned cattle. Its history, origin, description, and treatment
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521 Gutenberg downloadsen2011Difficulty 69 (Academic)Scientific American Supplement, No. 344, August 5, 1882
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521 Gutenberg downloadsen2005Difficulty 54 (Graduate)Himalayan Journals — Volume 2 Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.
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520 Gutenberg downloadsen2004Difficulty 69 (Academic)Text book of veterinary medicine, Volume 1 (of 5)
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520 Gutenberg downloadsen2023Difficulty 67 (Academic)Parasiten der Honigbiene und die durch dieselben bedingten Krankheiten dieses Insects.
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519 Gutenberg downloadsde2006Species Plantarum, Sections VI-X
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519 Gutenberg downloadsla2009Buffon's Natural History. Volume 07 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
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518 Gutenberg downloadsen2014Difficulty 60 (Graduate)General Anatomy, Applied to Physiology and Medicine, Vol. 2 (of 3)
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518 Gutenberg downloadsen2017Difficulty 61 (Academic)On the phenomena of variation and geographical distribution as illustrated by the Papilionidæ of the Malayan region
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518 Gutenberg downloadsen2024Difficulty 66 (Academic)Quadrupeds, What They Are and Where Found: A Book of Zoology for Boys
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518 Gutenberg downloadsen2007Difficulty 55 (Graduate)A Monograph on the Sub-class Cirripedia (Volume 2 of 2) The Balanidæ, (or Sessile Cirripedes); the Verrucidæ, etc., etc.
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517 Gutenberg downloadsen2014Difficulty 57 (Graduate)A Report upon the Mollusk Fisheries of Massachusetts
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517 Gutenberg downloadsen2015Difficulty 67 (Academic)Amphibians and Reptiles of the Rainforests of Southern El Petén, Guatemala
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517 Gutenberg downloadsen2011Difficulty 63 (Academic)The Structure and Life-history of the Cockroach (Periplaneta orientalis) An Introduction to the Study of Insects
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517 Gutenberg downloadsen2016Difficulty 58 (Graduate)Zoological Illustrations, Second Series, Volume 2 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
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517 Gutenberg downloadsen2013Difficulty 60 (Graduate)A Distributional Study of the Amphibians of the Isthmus of Tehuantepec, México
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516 Gutenberg downloadsen2011Difficulty 65 (Academic)The Child's Book of Nature Three parts in one
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516 Gutenberg downloadsen2018Difficulty 36 (High School)The romance of the animal world : $b Interesting descriptions of the strange & curious in natural history
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516 Gutenberg downloadsen2023Difficulty 63 (Academic)A Treatise on the Plague and Yellow Fever With an Appendix, containing histories of the plague at Athens in the time of the Peloponnesian War; at Constantinople in the time of Justinian; at London in 1665; at Marseilles in 1720
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515 Gutenberg downloadsen2022Difficulty 55 (Graduate)The Life and Letters of George John Romanes, M.A., LL.D., F.R.S.
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515 Gutenberg downloadsen2015Difficulty 52 (Graduate)Buffon's Natural History, Volume 03 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c.
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514 Gutenberg downloadsen2014Difficulty 68 (Academic)La simulación en la lucha por la vida
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514 Gutenberg downloadsen2013Difficulty 54 (Graduate)Theory of circulation by respiration : $b synopsis of its principles and history
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513 Gutenberg downloadsen2006Difficulty 57 (Graduate)Beginners' botany
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512 Gutenberg downloadsen2024Difficulty 50 (College)On Germinal Selection as a Source of Definite Variation
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512 Gutenberg downloadsen2010Difficulty 69 (Academic)A Revision of Snakes of the Genus Conophis (Family Colubridae, from Middle America)
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511 Gutenberg downloadsen2011Difficulty 59 (Graduate)Bacteria Especially as they are related to the economy of nature, to industrial processes, and to the public health
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511 Gutenberg downloadsen2015Difficulty 66 (Academic)The Biological Problem of To-day: Preformation Or Epigenesis? The Basis of a Theory of Organic Development
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511 Gutenberg downloadsen2011Difficulty 67 (Academic)The Botanical Magazine, Vol. 08 Or, Flower-Garden Displayed
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511 Gutenberg downloadsen2008Difficulty 60 (Graduate)The Geographical Distribution of Animals, Volume 1 With a study of the relations of living and extinct faunas as elucidating the past changes of the Earth's surface
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511 Gutenberg downloadsen2018Difficulty 58 (Graduate)Development of the Digestive Canal of the American Alligator
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510 Gutenberg downloadsen2007Difficulty 58 (Graduate)Mendel's principles of heredity: A defence
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510 Gutenberg downloadsen2022Difficulty 55 (Graduate)The House Fly and How to Suppress It
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510 Gutenberg downloadsen2006Difficulty 54 (Graduate)De Reis om de Wereld
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509 Gutenberg downloadsnl2010Het Leven der Dieren, Deel 3, Hoofdstuk 04: De Insecten
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509 Gutenberg downloadsnl2020Marvels of Pond-life Or, A Year's Microscopic Recreations Among the Polyps, Infusoria, Rotifers, Water-bears and Polyzoa
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509 Gutenberg downloadsen2011Difficulty 74 (Expert)The Naturalist in Nicaragua
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509 Gutenberg downloadsen2004Difficulty 63 (Academic)Catholic Churchmen in Science [First Series] Sketches of the Lives of Catholic Ecclesiastics Who Were Among the Great Founders in Science
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508 Gutenberg downloadsen2010Difficulty 67 (Academic)A Description of the Bar-and-Frame-Hive With an Abstract of Wildman's Complete Guide for the Management of Bees Throughout the Year
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507 Gutenberg downloadsen2006Difficulty 57 (Graduate)Appletons' Popular Science Monthly, March 1900 Vol. 56, Nov. 1899 to April, 1900
Various
507 Gutenberg downloadsen2014Difficulty 55 (Graduate)Die Cellularpathologie in ihrer Begründung auf physiologische und pathologische Gewebelehre
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507 Gutenberg downloadsde2014An Account of the Insects Noxious to Agriculture and Plants in New Zealand The Scale Insects (Coccididae)
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506 Gutenberg downloadsen2015Difficulty 53 (Graduate)Buffon's Natural History. Volume 09 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
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506 Gutenberg downloadsen2014Difficulty 54 (Graduate)Science and Morals and Other Essays
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506 Gutenberg downloadsen2008Difficulty 56 (Graduate)Travels into North America, Volume 2 (of 3)
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506 Gutenberg downloadsen2023Difficulty 47 (College)Buffon's Natural History. Volume 05 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
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505 Gutenberg downloadsen2014Difficulty 65 (Academic)De Wereld vóór de schepping van den mensch
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505 Gutenberg downloadsnl2006Coral and Coral Reefs
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504 Gutenberg downloadsen2001Difficulty 58 (Graduate)Grundriß der menschlichen Erblichkeitslehre und Rassenhygiene (2/2) Menschliche Auslese und Rassenhygiene
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504 Gutenberg downloadsde2015Studies in the Evolutionary Psychology of Feeling
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504 Gutenberg downloadsen2018Difficulty 62 (Academic)The zoology of the voyage of H.M.S. Beagle [vol. 2 of 5] : $b Mammalia
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504 Gutenberg downloadsen2022Difficulty 53 (Graduate)The zoology of the voyage of H.M.S. Beagle [vol. 3 of 5] : $b Birds
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504 Gutenberg downloadsen2024Difficulty 54 (Graduate)Buffon's Natural History. Volume 04 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
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502 Gutenberg downloadsen2014Difficulty 56 (Graduate)The Book of Love
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502 Gutenberg downloadsen2018Difficulty 72 (Expert)Les Phénomènes Psychiques Occultes: État Actuel de la Question
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501 Gutenberg downloadsfr2013A Taxonomic Study of the Middle American Snake, Pituophis deppei
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500 Gutenberg downloadsen2010Difficulty 58 (Graduate)Animal Life in Field and Garden
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500 Gutenberg downloadsen2021Difficulty 47 (College)Birds from Coahuila, Mexico
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500 Gutenberg downloadsen2008Difficulty 55 (Graduate)Essays on the Microscope Containing a Practical Description of the Most Improved Microscopes, a General History of Insects, etc., etc.
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500 Gutenberg downloadsen2020Difficulty 62 (Academic)General Anatomy, Applied to Physiology and Medicine, Vol. 3 (of 3)
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500 Gutenberg downloadsen2018Difficulty 61 (Academic)Variation in the Muscles and Nerves of the Leg in Two Genera of Grouse (Tympanuchus and Pedioecetes)
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500 Gutenberg downloadsen2013Difficulty 55 (Graduate)Science from an Easy Chair
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499 Gutenberg downloadsen2018Difficulty 52 (Graduate)The Fairy-Land of Science
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499 Gutenberg downloadsen2004Difficulty 48 (College)Darwinism stated by Darwin himself Characteristic passages from the writings of Charles Darwin
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498 Gutenberg downloadsen2022Difficulty 64 (Academic)Prehistoric man
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498 Gutenberg downloadsen2013Difficulty 57 (Graduate)The Academic Gregories
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498 Gutenberg downloadsen2016Difficulty 59 (Graduate)The Perpetuation of Living Beings, Hereditary Transmission and Variation Lecture IV. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
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498 Gutenberg downloadsen2001Difficulty 66 (Academic)Freshwater Sponges, Hydroids & Polyzoa
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497 Gutenberg downloadsen2011Difficulty 61 (Academic)Ecological Studies of the Timber Wolf in Northeastern Minnesota
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496 Gutenberg downloadsen2011Difficulty 52 (Graduate)Studies in the Theory of Descent (Volumes 1 and 2)
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495 Gutenberg downloadsen2015Difficulty 68 (Academic)The Scientific Evidences of Organic Evolution
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495 Gutenberg downloadsen2006Difficulty 67 (Academic)Zoological Illustrations, Second Series, Volume 1 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
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495 Gutenberg downloadsen2013Difficulty 59 (Graduate)Scientific American Supplement, No. 794, March 21, 1891
Various
494 Gutenberg downloadsen2005Difficulty 52 (Graduate)The Forests of Mount Rainier National Park
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494 Gutenberg downloadsen2010Difficulty 49 (College)Scientific American Supplement, No. 286, June 25, 1881
Various
493 Gutenberg downloadsen2005Difficulty 53 (Graduate)The Myxomycetes of the Miami Valley, Ohio
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493 Gutenberg downloadsen2009Difficulty 63 (Academic)A conchological manual
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492 Gutenberg downloadsen2013Difficulty 64 (Academic)Food Poisoning
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492 Gutenberg downloadsen2010Difficulty 65 (Academic)Journal of the Proceedings of the Linnean Society - Vol. 4 Zoology
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492 Gutenberg downloadsen2014Difficulty 61 (Academic)Keys to Fungi on Dung
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491 Gutenberg downloadsen2018Difficulty 57 (Graduate)On the Preparations of the Indian Hemp, or Gunjah (Cannabis Indica) Their Effects on the Animal System in Health, and Their Utility in the Treatment of Tetanus and Other Convulsive Diseases
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491 Gutenberg downloadsen2022Difficulty 63 (Academic)A Review of the Frogs of the Hyla bistincta Group
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490 Gutenberg downloadsen2010Difficulty 60 (Graduate)Darwinism and Race Progress
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490 Gutenberg downloadsen2014Difficulty 71 (Expert)Text book of veterinary medicine, Volume 2 (of 5)
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490 Gutenberg downloadsen2023Difficulty 66 (Academic)Manual of the apiary
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489 Gutenberg downloadsen2022Difficulty 49 (College)Evolution and Classification of the Pocket Gophers of the Subfamily Geomyinae
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488 Gutenberg downloadsen2012Difficulty 65 (Academic)Stories of the Universe: Animal Life
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488 Gutenberg downloadsen2012Difficulty 51 (Graduate)The Story of Creation as Told By Theology and By Science
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488 Gutenberg downloadsen2003Difficulty 62 (Academic)Greek Biology & Greek Medicine
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487 Gutenberg downloadsen2020Difficulty 56 (Graduate)Text book of veterinary medicine, Volume 3 (of 5)
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487 Gutenberg downloadsen2023Difficulty 63 (Academic)An Examination of Weismannism
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486 Gutenberg downloadsen2015Difficulty 74 (Expert)Appletons' Popular Science Monthly, February 1899 Volume LIV, No. 4, February 1899
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486 Gutenberg downloadsen2013Difficulty 57 (Graduate)The Evolution of Man — Volume 2
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486 Gutenberg downloadsen2004Difficulty 55 (Graduate)British Sea Birds
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485 Gutenberg downloadsen2014Difficulty 61 (Academic)The Evolution of Man — Volume 1
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485 Gutenberg downloadsen2004Difficulty 52 (Graduate)The Life of the Weevil
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485 Gutenberg downloadsen2021Difficulty 49 (College)A history of land mammals in the western hemisphere
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484 Gutenberg downloadsen2025Difficulty 66 (Academic)Physiological Researches on Life and Death
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484 Gutenberg downloadsen2018Difficulty 60 (Graduate)Fear
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483 Gutenberg downloadsen2019Difficulty 59 (Graduate)Systematics of Megachiropteran Bats in the Solomon Islands
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483 Gutenberg downloadsen2012Difficulty 58 (Graduate)Buffon's Natural History. Volume 10 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
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482 Gutenberg downloadsen2014Difficulty 61 (Academic)Little Busybodies: The Life of Crickets, Ants, Bees, Beetles, and Other Busybodies
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482 Gutenberg downloadsen2007Difficulty 34 (High School)The Botanical Magazine, Vol. 03 Or, Flower-Garden Displayed
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482 Gutenberg downloadsen2006Difficulty 57 (Graduate)The Salmon Fishery of Penobscot Bay and River in 1895-96
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482 Gutenberg downloadsen2005Difficulty 48 (College)A New Order of Fishlike Amphibia From the Pennsylvanian of Kansas
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481 Gutenberg downloadsen2010Difficulty 55 (Graduate)Het Leven der Dieren: Deel 1, Hoofdstuk 04: De Roofdieren
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481 Gutenberg downloadsnl2006Note on the Resemblances and Differences in the Structure and the Development of the Brain in Man and Apes
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481 Gutenberg downloadsen2000Difficulty 66 (Academic)Poisonous Snakes of Texas and First Aid Treatment of Their Bites Bulletin No. 31
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481 Gutenberg downloadsen2017Difficulty 58 (Graduate)Common objects of the microscope
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480 Gutenberg downloadsen2017Difficulty 69 (Academic)Zoological Illustrations, Volume 2 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
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480 Gutenberg downloadsen2012Difficulty 62 (Academic)Ecological Observations on the Woodrat, Neotoma floridana
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479 Gutenberg downloadsen2010Difficulty 59 (Graduate)The Sacred Beetle, and Others
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479 Gutenberg downloadsen2021Difficulty 56 (Graduate)Comments on the Taxonomy and Geographic Distribution of Some North American Marsupials, Insectivores and Carnivores
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478 Gutenberg downloadsen2010Difficulty 58 (Graduate)Ohio Biological Survey, Bull. 10, Vol. 11, No. 6 The Ascomycetes of Ohio IV and V
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478 Gutenberg downloadsen2006Difficulty 58 (Graduate)Speciation of the Wandering Shrew
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478 Gutenberg downloadsen2011Difficulty 62 (Academic)Evolution: Its nature, its evidence, and its relation to religious thought
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477 Gutenberg downloadsen2014Difficulty 88 (Specialist)The apiary; or, bees, bee-hives, and bee culture [1865] Being a familiar account of the habits of bees, and the most improved methods of management, with full directions, adapted for the cottager, farmer, or scientific apiarian
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477 Gutenberg downloadsen2022Difficulty 63 (Academic)Het Leven der Dieren: Deel 1, Hoofdstuk 01: De Apen
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476 Gutenberg downloadsnl2005Insects and Diseases of Trees in the South
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476 Gutenberg downloadsen2015Difficulty 55 (Graduate)Speciation and Evolution of the Pygmy Mice, Genus Baiomys
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476 Gutenberg downloadsen2011Difficulty 64 (Academic)The Mason-Wasps
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476 Gutenberg downloadsen2021Difficulty 50 (College)Zakflora voor Suriname [Deel I] Bulletin van het Koloniaal Museum te Haarlem No. 47.
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476 Gutenberg downloadsnl2017The Evolutionist at Large
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475 Gutenberg downloadsen2014Difficulty 55 (Graduate)The Natural History of Chocolate Being a Distinct and Particular Account of the Cocoa-Tree, its Growth and Culture, and the Preparation, Excellent Properties, and Medicinal Vertues of its Fruit
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475 Gutenberg downloadsen2008Difficulty 52 (Graduate)The Story of Milk
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475 Gutenberg downloadsen2021Difficulty 64 (Academic)Useful Knowledge: Volume 3. Animals Or, a familiar account of the various productions of nature
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475 Gutenberg downloadsen2018Difficulty 54 (Graduate)Agricultural zoology
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474 Gutenberg downloadsen2025Difficulty 52 (Graduate)Stray Feathers From a Bird Man's Desk
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474 Gutenberg downloadsen2021Difficulty 54 (Graduate)The Body at Work: A Treatise on the Principles of Physiology
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473 Gutenberg downloadsen2020Difficulty 54 (Graduate)Physiology: The Science of the Body
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472 Gutenberg downloadsen2015Difficulty 53 (Graduate)Aphorisms and Reflections from the Works of T. H. Huxley
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470 Gutenberg downloadsen2011Difficulty 60 (Graduate)Journal of Entomology and Zoology, Vol. 11, No. 4, December 1919
Various
470 Gutenberg downloadsen2011Difficulty 54 (Graduate)The Arena, Volume 18, No. 93, August, 1897
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470 Gutenberg downloadsen2010Difficulty 51 (Graduate)An Elementary Text-book of the Microscope including a description of the methods of preparing and mounting objects, etc.
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469 Gutenberg downloadsen2015Difficulty 52 (Graduate)Dissection of the Platana and the Frog
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468 Gutenberg downloadsen2022Difficulty 55 (Graduate)The Tower Menagerie : $b comprising the natural history of the animals contained in that establishment; with anecdotes of their characters and history.
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468 Gutenberg downloadsen2016Difficulty 77 (Expert)More Beetles
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467 Gutenberg downloadsen2022Difficulty 47 (College)A Preliminary Revision of the North American Species of Cactus, Anhalonium, and Lophophora
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466 Gutenberg downloadsen1998Difficulty 56 (Graduate)A Text-Book of Horseshoeing, for Horseshoers and Veterinarians
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466 Gutenberg downloadsen2021Difficulty 55 (Graduate)Discourses: Biological & Geological Essays
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466 Gutenberg downloadsen2003Difficulty 61 (Academic)The Destiny of Man, Viewed in the Light of His Origin
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466 Gutenberg downloadsen2005Difficulty 65 (Academic)A Synopsis of the American Bats of the Genus Pipistrellus
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465 Gutenberg downloadsen2010Difficulty 58 (Graduate)Birds in Flight
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465 Gutenberg downloadsen2014Difficulty 54 (Graduate)Buffon's Natural History. Volume 08 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
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465 Gutenberg downloadsen2014Difficulty 61 (Academic)Die Welträtsel: Gemeinverständliche Studien über Monistische Philosophie
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465 Gutenberg downloadsde2019Ornithological biography, Vol. 4 (of 5) : $b An account of the habits of the birds of the United States of America
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465 Gutenberg downloadsen2023Difficulty 62 (Academic)Regeneration
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465 Gutenberg downloadsen2018Difficulty 57 (Graduate)The Farmer's Veterinarian: A Practical Treatise on the Diseases of Farm Stock
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464 Gutenberg downloadsnl2007Les énigmes de l'Univers
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464 Gutenberg downloadsfr2012New England Salmon Hatcheries and Salmon Fisheries in the Late 19th Century
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464 Gutenberg downloadsen2005Difficulty 53 (Graduate)Q. E. D., or New Light on the Doctrine of Creation
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464 Gutenberg downloadsen2004Difficulty 67 (Academic)Scientific American Supplement, No. 664, September 22,1888
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464 Gutenberg downloadsen2008Difficulty 58 (Graduate)Appletons' Popular Science Monthly, May, 1900 Vol. 57, May, 1900 to October, 1900
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463 Gutenberg downloadsen2014Difficulty 60 (Graduate)Birds' Nests, Eggs and Egg-Collecting
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462 Gutenberg downloadsen2014Difficulty 65 (Academic)Jaw Musculature of the Mourning and White-winged Doves
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462 Gutenberg downloadsen2010Difficulty 58 (Graduate)Measles
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462 Gutenberg downloadsen2006Difficulty 50 (College)An Expository Outline of the "Vestiges of the Natural History of Creation" With a Notice of the Author's "Explanations:" A Sequel to the Vestiges
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461 Gutenberg downloadsen2006Difficulty 66 (Academic)Anthropoid apes
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461 Gutenberg downloadsen2025Difficulty 53 (Graduate)British Museum (Natural History) General Guide
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461 Gutenberg downloadsen2018Difficulty 69 (Academic)The Systematics of the Frogs of the Hyla Rubra Group in Middle America
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460 Gutenberg downloadsen2010Difficulty 60 (Graduate)Descripción Geografica, Histórica y Estadística de Bolivia, Tomo 1.
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459 Gutenberg downloadses2004God and the World: A Survey of Thought
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459 Gutenberg downloadsen2009Difficulty 60 (Graduate)Food Habits of the Thrushes of the United States
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457 Gutenberg downloadsen2010Difficulty 54 (Graduate)Mazedonien : $b Erlebnisse und Beobachtungen eines Naturforschers im Gefolge des deutschen Heeres
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457 Gutenberg downloadsde2023Garden Pests in New Zealand A Popular Manual for Practical Gardeners, Farmers and Schools
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456 Gutenberg downloadsen2014Difficulty 71 (Expert)Natural History of the Prairie Vole (Mammalian Genus Microtus) [KU. Vol. 1 No. 7]
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456 Gutenberg downloadsen2011Difficulty 52 (Graduate)The ivory king : $b A popular history of the elephant and its allies
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456 Gutenberg downloadsen2022Difficulty 58 (Graduate)Time and Life: Mr. Darwin's "Origin of Species"
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456 Gutenberg downloadsen2001Difficulty 72 (Expert)How to Know the Ferns
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455 Gutenberg downloadsen2014Difficulty 50 (College)Evolution: An Investigation and a Critique
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454 Gutenberg downloadsen2006Difficulty 62 (Academic)An Account of the Late Improvements in Galvanism With a Series of Curious and Interesting Experiments Performed Before the Commissioners of the French National Institute, and Repeated Lately in the Anatomical Theatres of London
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453 Gutenberg downloadsen2018Difficulty 64 (Academic)Darwin, and After Darwin, Volume 2 of 3 Post-Darwinian Questions: Heredity and Utility
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453 Gutenberg downloadsen2011Difficulty 64 (Academic)The micro-organisms of the soil
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452 Gutenberg downloadsen2025Difficulty 61 (Academic)Common Diseases of Farm Animals
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451 Gutenberg downloadsen2005Difficulty 55 (Graduate)Fishes of Chautauqua, Cowley and Elk Counties, Kansas
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451 Gutenberg downloadsen2010Difficulty 55 (Graduate)The Dancing Mouse: A Study in Animal Behavior
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451 Gutenberg downloadsen2005Difficulty 64 (Academic)The Popular Science Monthly, August, 1900 Vol. 57, May, 1900 to October, 1900
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451 Gutenberg downloadsen2014Difficulty 68 (Academic)Dans la Haute-Gambie : $b Voyage d'exploration scientifique, 1891-1892
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450 Gutenberg downloadsfr2024Fathers of Biology
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450 Gutenberg downloadsen2008Difficulty 64 (Academic)Memorias sobre a influencia dos descobrimentos portuguezes no conhecimento das plantas I. - Memoria sobre a Malagueta
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450 Gutenberg downloadspt2009Migration of Birds (1979)
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450 Gutenberg downloadsen2021Difficulty 68 (Academic)Souvenirs entomologiques - Livre I Étude sur l'instinct et les moeurs des insectes
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450 Gutenberg downloadsfr2005The Orchid Album, Volume 3 Comprising Coloured Figures and Descriptions of New, Rare, and Beautiful Orchidaceous Plants
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450 Gutenberg downloadsen2019Difficulty 57 (Graduate)Illustrations of the Birds of California, Texas, Oregon, British and Russian America
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448 Gutenberg downloadsen2021Difficulty 63 (Academic)The botanist's repository for new and rare plants; vol. 03 & 04 [of 10]
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448 Gutenberg downloadsen2024Difficulty 55 (Graduate)I funghi mangerecci e velenosi dell'Europa media con speciale riguardo a quelli che crescono nel Trentino - II edizione riveduta ed aumentata
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447 Gutenberg downloadsit2013The Botanical Magazine, Vol. 06 Or, Flower-Garden Displayed
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447 Gutenberg downloadsen2007Difficulty 59 (Graduate)Experimentelle Untersuchungen über die Frage »Ist die Furcht vor Krankheitsübertragung durch das Telephon berechtigt«? Inaugural-Dissertation zur Erlangung der Doktorwürde in der Medizin, Chirurgie und Geburtshülfe der Hohen Medizinischen Fakultät der Königlichen Universität Greifswald
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446 Gutenberg downloadsde2008Illustrations of Exotic Entomology, Volume 2
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446 Gutenberg downloadsen2014Difficulty 55 (Graduate)The history of a mouthful of bread : $b and its effect on the organization of men and animals
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446 Gutenberg downloadsen2004Difficulty 49 (College)The Crayfish: An Introduction to the Study of Zoology.
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445 Gutenberg downloadsen2019Difficulty 54 (Graduate)Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, I. Band Von den Anfängen bis zum Wiederaufleben der Wissenschaften
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444 Gutenberg downloadsde2016Respiration Calorimeters for Studying the Respiratory Exchange and Energy Transformations of Man
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444 Gutenberg downloadsen2009Difficulty 65 (Academic)Scientific Essays and Lectures
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443 Gutenberg downloadsen2003Difficulty 56 (Graduate)The book of antelopes, vol. 4 (of 4)
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443 Gutenberg downloadsen2023Difficulty 48 (College)The Universal Kinship
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443 Gutenberg downloadsen2020Difficulty 54 (Graduate)Colouration in Animals and Plants
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442 Gutenberg downloadsen2014Difficulty 56 (Graduate)The book of antelopes, vol. 2 (of 4)
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442 Gutenberg downloadsen2023Difficulty 48 (College)The Flea
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442 Gutenberg downloadsen2014Difficulty 53 (Graduate)The Birds of Australia, Vol. 1 of 7
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441 Gutenberg downloadsen2021Difficulty 45 (College)The Fishing Industry
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441 Gutenberg downloadsen2016Difficulty 54 (Graduate)A Quantitative Study of the Nocturnal Migration of Birds
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440 Gutenberg downloadsen2011Difficulty 55 (Graduate)An ethical problem; or, Sidelights upon scientific experimentation on man and animals
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440 Gutenberg downloadsen2006Difficulty 64 (Academic)Aromatics and the Soul: A Study of Smells
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440 Gutenberg downloadsen2019Difficulty 53 (Graduate)Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, IV. Band Das Emporblühen der modernen Naturwissenschaften seit der Entdeckung des Energieprinzips
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440 Gutenberg downloadsde2019Journal of Entomology and Zoology, Vol. 11, No. 2, June 1919
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440 Gutenberg downloadsen2010Difficulty 54 (Graduate)The Naturalist's Repository, Volume 1 (of 5) or Monthly Miscellany of Exotic Natural History: etc. etc.
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440 Gutenberg downloadsen2017Difficulty 76 (Expert)Evolution and creation
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439 Gutenberg downloadsen2017Difficulty 64 (Academic)Evolution of Life and Form Four lectures delivered at the twenty-third anniversary meeting of the Theosophical Society at Adyar, Madras, 1898
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439 Gutenberg downloadsen2012Difficulty 60 (Graduate)The Essentials of Illustration A Practical Guide to the Reproduction of Drawings & Photographs for the Use of Scientists & Others
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439 Gutenberg downloadsen2011Difficulty 58 (Graduate)The Hunting Wasps
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439 Gutenberg downloadsen2022Difficulty 57 (Graduate)Aspects of plant life; with special reference to the British flora
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438 Gutenberg downloadsen2018Difficulty 59 (Graduate)Het Leven der Dieren. Derde Deel, Hoofdstuk 1 tot 4, De Kruipende Dieren
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438 Gutenberg downloadsnl2014The Pros and Cons of Vivisection
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438 Gutenberg downloadsen2011Difficulty 63 (Academic)On the phenomena of hybridity in the genus Homo
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437 Gutenberg downloadsen2014Difficulty 66 (Academic)Travels into North America, Volume 3 (of 3)
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437 Gutenberg downloadsen2024Difficulty 50 (College)A Field Study of the Kansas Ant-Eating Frog, Gastrophryne olivacea
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436 Gutenberg downloadsen2010Difficulty 55 (Graduate)A Mechanical Account of Poisons in Several Essays
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436 Gutenberg downloadsen2016Difficulty 73 (Expert)Handboek voor den kaasmaker in Nederland
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436 Gutenberg downloadsnl2010The Doctrine of Evolution: Its Basis and Its Scope
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436 Gutenberg downloadsen2005Difficulty 65 (Academic)Bees
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435 Gutenberg downloadsen2015Difficulty 52 (Graduate)The Study of Plant Life
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435 Gutenberg downloadsen2019Difficulty 43 (College)House Rats and Mice
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434 Gutenberg downloadsen2011Difficulty 51 (Graduate)Life's Dawn on Earth Being the history of the oldest known fossil remains, and their relations to geological time and to the development of the animal kingdom
Dawson, John William, Sir
434 Gutenberg downloadsen2015Difficulty 58 (Graduate)Mammals Obtained by Dr. Curt von Wedel from the Barrier Beach of Tamaulipas, Mexico
Hall, E. Raymond (Eugene Raymond)
434 Gutenberg downloadsen2009Difficulty 53 (Graduate)The honey-bee: its nature, homes and products
Harris, William Hetherington
433 Gutenberg downloadsen2022Difficulty 56 (Graduate)Westafrikanische Kautschuk-Expedition
Schlechter, Rudolf & Deutsche Kolonialgesellschaft. Kolonial-Wirtschaftliches Komitee
433 Gutenberg downloadsde2022Louis Agassiz as a Teacher; illustrative extracts on his method of instruction
Cooper, Lane
432 Gutenberg downloadsen2004Difficulty 56 (Graduate)The Popular Science Monthly, June, 1900 Vol. 57, May, 1900 to October, 1900
Various
432 Gutenberg downloadsen2014Difficulty 69 (Academic)Die Tier- und Pflanzenwelt des Süsswassers. Erster Band.
Forel, F. A. (François Alphonse) & Gruber, August & Ludwig, Friedrich & Migula, W. (Walter) & Plate, Ludwig & Vosseler, Julius & Weltner, Wilhelm
431 Gutenberg downloadsde2024Evolution and Adaptation
Morgan, Thomas Hunt
431 Gutenberg downloadsen2020Difficulty 62 (Academic)Grundzüge der Paläontologie (Paläozoologie). 1. Abteilung: Invertebrata.
Zittel, Karl Alfred von
431 Gutenberg downloadsde2023Handbuch der Pharmakognosie : $b Zweiter Band. Spezielle Pharmakognosie
Tschirch, A. (Alexander)
431 Gutenberg downloadsde2023Reis door Noord Amerika : $b Gedaan door den Heer Pieter Kalm
Kalm, Pehr
430 Gutenberg downloadsnl2023The winners in life's race : $b Or, the great backboned family
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430 Gutenberg downloadsen2024Difficulty 63 (Academic)A Dissertation on Horses Wherein It is Demonstrated, by Matters of Fact, as Well as from the Principles of Philosophy, That Innate Qualities Do Not Exist, and That the Excellence of This Animal is Altogether Mechanical and Not in the Blood
Osmer, William
429 Gutenberg downloadsen2004Difficulty 64 (Academic)A first book in organic evolution
Shute, D. Kerfoot (Daniel Kerfoot)
429 Gutenberg downloadsen2024Difficulty 58 (Graduate)Die Tier- und Pflanzenwelt des Süsswassers. Zweiter Band.
Apstein, C. (Carl Heinrich) & Borcherding, Friedrich & Clessin, Stephan & Kramer, Paul & Schmidt-Schwedt, E. & Seligo, Arthur & Zschokke, Friedrich
429 Gutenberg downloadsde2024Journal of Entomology and Zoology, Vol. 09, No. 1, March 1917
Various
429 Gutenberg downloadsen2015Difficulty 53 (Graduate)The Forest Habitat of the University of Kansas Natural History Reservation
Fitch, Henry S. (Henry Sheldon) & McGregor, Ronald L.
429 Gutenberg downloadsen2010Difficulty 59 (Graduate)ABC's of Science
Oliver, Charles A. (Charles Alexander)
427 Gutenberg downloadsen1998Difficulty 51 (Graduate)Der Unterkiefer des Homo Heidelbergensis: Aus den Sanden von Mauer bei Heidelberg
Schoetensack, Otto
427 Gutenberg downloadsde2011Guide to the study of animal ecology
Adams, Charles C. (Charles Christopher)
427 Gutenberg downloadsen2023Difficulty 66 (Academic)Le Tour du Monde; Voyage d'un naturaliste. Journal des voyages et des voyageurs; 2. sem. 1860
Various
427 Gutenberg downloadsfr2008The Birds of Australia, Vol. 5 of 7
Gould, John
427 Gutenberg downloadsen2020Difficulty 61 (Academic)A Discourse on the Plague
Mead, Richard
426 Gutenberg downloadsen2010Difficulty 61 (Academic)Daedalus : $b or, Science and the future
Haldane, J. B. S. (John Burdon Sanderson)
426 Gutenberg downloadsen2023Difficulty 58 (Graduate)De afstamming van den mensch en de seksueele teeltkeus, deel 2 (van 2)
Darwin, Charles
426 Gutenberg downloadsnl2024Scientific American magazine, Vol. 2 Issue 1 The advocate of Industry and Journal of Scientific, Mechanical and Other Improvements
Various
426 Gutenberg downloadsen2009Difficulty 52 (Graduate)Phylogeny of the Waxwings and Allied Birds
Arvey, M. Dale (Martin Dale)
424 Gutenberg downloadsen2010Difficulty 66 (Academic)The Brain, A Decoded Enigma
Moisa, Dorin Teodor
424 Gutenberg downloadsen2005Difficulty 58 (Graduate)The horse's mouth, showing the age by the teeth
Mayhew, Edward
423 Gutenberg downloadsen2014Difficulty 55 (Graduate)The Subspecific Status of Two Central American Sloths
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
423 Gutenberg downloadsen2010Difficulty 62 (Academic)Animal Castration
Liautard, Alexandre François Augustin
422 Gutenberg downloadsen2019Difficulty 71 (Expert)Systematic Status of the Colubrid Snake, Leptodeira discolor Günther
Duellman, William Edward
422 Gutenberg downloadsen2011Difficulty 63 (Academic)Life and death
Dastre, A. (Albert)
421 Gutenberg downloadsen2021Difficulty 56 (Graduate)The Genera of Phyllomedusine Frogs (Anura: Hylidae)
Duellman, William Edward
420 Gutenberg downloadsen2010Difficulty 74 (Expert)Through a Microscope Something of the Science, Together with many Curious Observations Indoor and Out and Directions for a Home-made Microscope.
Wells, Samuel & Sargent, Frederick Leroy & Treat, Mary
420 Gutenberg downloadsen2011Difficulty 48 (College)Aus den Tiefen des Weltmeeres Schilderungen von der deutschen Tiefsee-Expedition
Chun, Carl
419 Gutenberg downloadsde2014Lamarck et son OEuvre
Corra, Emile
419 Gutenberg downloadsfr2012The Deseado Formation of Patagonia
Loomis, Frederic Brewster
419 Gutenberg downloadsen2024Difficulty 61 (Academic)The Natural History of the Tea-Tree, with Observations on the Medical Qualities of Tea, and on the Effects of Tea-Drinking
Lettsom, John Coakley
419 Gutenberg downloadsen2021Difficulty 52 (Graduate)A New Extinct Emydid Turtle from the Lower Pliocene of Oklahoma
Galbreath, Edwin C. (Edwin Carter)
418 Gutenberg downloadsen2010Difficulty 59 (Graduate)Earthworms and Their Allies
Beddard, Frank E. (Frank Evers)
418 Gutenberg downloadsen2013Difficulty 59 (Graduate)Flowers and their friends
Morley, Margaret Warner
418 Gutenberg downloadsen2024Difficulty 39 (High School)Harvesting Ants and Trap-Door Spiders Notes and Observations on Their Habits and Dwellings
Moggridge, John Traherne
418 Gutenberg downloadsen2021Difficulty 54 (Graduate)Influenza : $b An epidemiologic study
Vaughan, Warren T. (Warren Taylor)
418 Gutenberg downloadsen2023Difficulty 66 (Academic)Noteworthy Mammals from Sinaloa, Mexico
Jones, J. Knox & Alvarez, Ticul & Lee, M. Raymond
418 Gutenberg downloadsen2010Difficulty 52 (Graduate)Rust, Smut, Mildew, & Mould: An Introduction to the Study of Microscopic Fungi
Cooke, M. C. (Mordecai Cubitt)
417 Gutenberg downloadsen2020Difficulty 61 (Academic)The Dolphin in History
Montagu, Ashley & Lilly, John Cunningham
417 Gutenberg downloadsen2019Difficulty 56 (Graduate)Aspects of Reproduction and Development in the Prairie Vole (Microtus ochrogaster)
Fitch, Henry S. (Henry Sheldon)
416 Gutenberg downloadsen2011Difficulty 60 (Graduate)Dr. B. Mure's materia medica : $b or, provings of the principal animal and vegetable poisons of the Brazilian Empire, and their application in the treatment of disease
Mure, Benoît
416 Gutenberg downloadsen2023Difficulty 45 (College)Myology and Serology of the Avian Family Fringillidae: A Taxonomic Study
Stallcup, William B.
416 Gutenberg downloadsen2010Difficulty 65 (Academic)A Theory of Creation: A Review of 'Vestiges of the Natural History of Creation'
Bowen, Francis
415 Gutenberg downloadsen2008Difficulty 67 (Academic)Improved Queen-Rearing; or, How to Rear Large, Prolific, Long-Lived Queen Bees The Result of Nearly Half a Century's Experience in Rearing Queen Bees, Giving the Practical, Every-day Work of the Queen-Rearing Apiary
Alley, Henry
415 Gutenberg downloadsen2019Difficulty 48 (College)Radioisotopes and Life Processes (Revised)
Kisieleski, Walter E. & Baserga, Renato
415 Gutenberg downloadsen2015Difficulty 66 (Academic)The Ancestry of Modern Amphibia: A Review of the Evidence
Eaton, Theodore H. (Theodore Hildreth)
415 Gutenberg downloadsen2011Difficulty 69 (Academic)The Breeding Birds of Kansas
Johnston, Richard F.
415 Gutenberg downloadsen2011Difficulty 74 (Expert)Vivisection
Leffingwell, Albert
415 Gutenberg downloadsen2010Difficulty 64 (Academic)Wasps, Social and Solitary
Peckham, George W. (George Williams) & Peckham, E. G. (Elizabeth Gifford)
415 Gutenberg downloadsen2014Difficulty 60 (Graduate)Embryology: The Beginnings of Life
Leighton, Gerald R. (Gerald Rowley)
414 Gutenberg downloadsen2011Difficulty 59 (Graduate)La vie des termites
Maeterlinck, Maurice
414 Gutenberg downloadsfr2024Preservation of Bull Semen at Sub-Zero Temperatures
VanDemark, N. L. & Friedman, M. E. & Kinney, W. C. & Miller, W. J. & Rodriguez, Carlos
414 Gutenberg downloadsen2011Difficulty 62 (Academic)Introduction to the Study of Palæontological Botany
Balfour, John Hutton
413 Gutenberg downloadsen2016Difficulty 55 (Graduate)Systematic Status of a South American Frog, Allophryne ruthveni Gaige
Lynch, John D. & Freeman, Howard L.
413 Gutenberg downloadsen2010Difficulty 63 (Academic)Illustrations of Exotic Entomology, Volume 3
Drury, Dru
412 Gutenberg downloadsen2014Difficulty 57 (Graduate)Little Masterpieces of Science: Health and Healing
Unknown
412 Gutenberg downloadsen2014Difficulty 53 (Graduate)Occurrence of the Garter Snake, Thamnophis sirtalis, in the Great Plains and Rocky Mountains
Fitch, Henry S. (Henry Sheldon) & Maslin, T. Paul
412 Gutenberg downloadsen2010Difficulty 66 (Academic)Popular Lectures on Zoonomia Or The Laws of Animal Life, in Health and Disease
Garnett, Thomas
412 Gutenberg downloadsen2009Difficulty 59 (Graduate)The Birds of Australia, Vol. 2 of 7
Gould, John
412 Gutenberg downloadsen2019Difficulty 66 (Academic)The Darwinian Hypothesis
Huxley, Thomas Henry
412 Gutenberg downloadsen2001Difficulty 69 (Academic)Botanical features of the Algerian Sahara
Cannon, William Austin
411 Gutenberg downloadsen2023Difficulty 52 (Graduate)Heroes of science : $b Botanists, zoologists, and geologists
Duncan, P. Martin (Peter Martin)
411 Gutenberg downloadsen2023Difficulty 58 (Graduate)The Subspecies of the Mountain Chickadee
Grinnell, Joseph
411 Gutenberg downloadsen2010Difficulty 50 (College)A Population Study of the Prairie Vole (Microtus ochrogaster) in Northeastern Kansas
Martin, Edwin Perry
410 Gutenberg downloadsen2012Difficulty 61 (Academic)Biology : $b A lecture delivered at Columbia University in the series on Science, Philosophy and Art November 20, 1907
Wilson, Edmund B. (Edmund Beecher)
410 Gutenberg downloadsen2006Difficulty 69 (Academic)Epidemic Respiratory Disease The pneumonias and other infections of the repiratory tract accompanying influenza and measles
Opie, Eugene L. (Eugene Lindsay) & Blake, Francis G. (Francis Gilman) & Rivers, Thomas M. (Thomas Milton) & Small, James C. (James Craig)
410 Gutenberg downloadsen2020Difficulty 67 (Academic)Nouvel atlas de poche des champignons Comestibles et Vénéneux les plus répandus. Série II (Première édition)
Dumée, Paul
410 Gutenberg downloadsfr2017A New Subspecies of Lizard, Cnemidophorus sacki, from Michoacán, México
Duellman, William Edward
409 Gutenberg downloadsen2010Difficulty 58 (Graduate)Birds Found on the Arctic Slope of Northern Alaska
Bee, James W.
409 Gutenberg downloadsen2010Difficulty 42 (College)Descriptions of New Hylid Frogs From Mexico and Central America
Duellman, William Edward
409 Gutenberg downloadsen2010Difficulty 64 (Academic)Physiological economy in nutrition, with special reference to the minimal proteid requirement of the healthy man an experimental study
Chittenden, R. H. (Russell Henry)
409 Gutenberg downloadsen2022Difficulty 66 (Academic)The Botanical Magazine, Vol. 13 Or, Flower-Garden Displayed
Curtis, William & Sims, John
409 Gutenberg downloadsen2013Difficulty 58 (Graduate)Natur und Mensch Sechs Abschnitte aus Werken von Ernst Haeckel
Haeckel, Ernst
408 Gutenberg downloadsde2015Woher die Kindlein kommen
Hoppeler, Hans
408 Gutenberg downloadsde2009A Profitable Instruction of the Perfite Ordering of Bees With the Maruellous Nature, Propertie, and Gouernemente of Them: and the Necessarie Vses Both of Their Honie and Waxe, Seruing Diuersly, as Well in Inward as Outward Causes: Gathered Out of the Best Writers
Hill, Thomas
407 Gutenberg downloadsen2014Difficulty 50 (College)Nouvel atlas de poche des champignons Comestibles et Vénéneux les plus répandus. Série I (Troisième édition) Suivi de notions générales sur les champignons, leur classification, composition chimique, valeur alimentaire, préparation
Dumée, Paul
407 Gutenberg downloadsfr2010Handboek voor Bijenhouders
Dirks, J.
406 Gutenberg downloadsnl2010Het Leven der Dieren: Deel 1, Hoofdstuk 07: De Knaagdieren
Brehm, Alfred Edmund
406 Gutenberg downloadsnl2007The British Woodlice Being a Monograph of the Terrestrial Isopod Crustacea Occurring in the British Islands
Webb, Wilfred Mark & Sillem, Charles
406 Gutenberg downloadsen2013Difficulty 58 (Graduate)The Wild Elephant and the Method of Capturing and Taming it in Ceylon
Tennent, James Emerson, Sir
406 Gutenberg downloadsen2018Difficulty 65 (Academic)Het Leven der Dieren: Deel 2, Hoofdstuk 01: De Boomvogels.
Brehm, Alfred Edmund
405 Gutenberg downloadsnl2009Inheritance of Characteristics in Domestic Fowl
Davenport, Charles Benedict
405 Gutenberg downloadsen2015Difficulty 50 (College)Through a pocket lens
Scherren, Henry
405 Gutenberg downloadsen2022Difficulty 43 (College)A Manual of Conchology According to the System Laid Down by Lamarck, with the Late Improvements by De Blainville. Exemplified and Arranged for the Use of Students.
Wyatt, Thomas
404 Gutenberg downloadsen2018Difficulty 58 (Graduate)Kyphosis and other Variations in Soft-shelled Turtles
Smith, Hobart M. (Hobart Muir)
404 Gutenberg downloadsen2010Difficulty 46 (College)Beginselen der dierkunde
Ritzema Bos, J. (Jan)
403 Gutenberg downloadsnl2010Chambers's Journal of Popular Literature, Science, and Art, No. 683 January 27, 1877
Various
403 Gutenberg downloadsen2014Difficulty 50 (College)Cranial Osteology of the Hylid Frog, Smilisca baudini
Trueb, Linda
403 Gutenberg downloadsen2010Difficulty 61 (Academic)Lajien synty: Luonnollisen valinnan kautta
Darwin, Charles
403 Gutenberg downloadsfi2016Les grands froids
Bouant, Emile
403 Gutenberg downloadsfr2013The flowering plants of South Africa; vol. 4
Pole Evans, I. B. (Illtyd Buller)
403 Gutenberg downloadsen2023Difficulty 49 (College)In sloot en plas
Heimans, Eli & Thijsse, Jac. P. (Jacobus Pieter)
402 Gutenberg downloadsnl2022The Vivisectors' Directory Being a list of the licensed vivisectors in the United Kingdom, together with the leading physiologists in foreign laboratories
Unknown
402 Gutenberg downloadsen2017Difficulty 61 (Academic)Studies on Epidemic Influenza: Comprising Clinical and Laboratory Investigations
University of Pittsburgh. School of Medicine
401 Gutenberg downloadsen2019Difficulty 62 (Academic)The alligator and its allies
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401 Gutenberg downloadsen2023Difficulty 53 (Graduate)Studies of trees in winter : $b A description of the deciduous trees of northeastern America
Huntington, Annie Oakes
400 Gutenberg downloadsen2024Difficulty 51 (Graduate)Subspeciation in Pocket Gophers of Kansas, [KU. Vol. 1 No. 11]
Villa Ramírez, Bernardo & Hall, E. Raymond (Eugene Raymond)
400 Gutenberg downloadsen2011Difficulty 58 (Graduate)The genetic and the operative evidence relating to secondary sexual characters
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400 Gutenberg downloadsen2018Difficulty 47 (College)Atoms, Nature, and Man: Man-made Radioactivity in the Environment
Hines, Neal O.
399 Gutenberg downloadsen2015Difficulty 68 (Academic)Essays in eugenics
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399 Gutenberg downloadsen2024Difficulty 59 (Graduate)Geographic Variation in the North American Cyprinid Fish, Hybopsis gracilis
Olund, Leonard J. & Cross, Frank B. (Frank Bernard)
399 Gutenberg downloadsen2011Difficulty 57 (Graduate)Fishes of the Big Blue River Basin, Kansas
Minckley, W. L.
398 Gutenberg downloadsen2011Difficulty 47 (College)Half Hours With Modern Scientists: Lectures and Essays
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398 Gutenberg downloadsen2021Difficulty 66 (Academic)The Popular Science Monthly, July, 1900 Vol. 57, May, 1900 to October, 1900
Various
398 Gutenberg downloadsen2014Difficulty 56 (Graduate)Two New Meadow Mice from Michoacán Mexico
Hall, E. Raymond (Eugene Raymond)
398 Gutenberg downloadsen2010Difficulty 60 (Graduate)Animal portraiture
Lydekker, Richard
397 Gutenberg downloadsen2023Difficulty 58 (Graduate)Fish Populations, Following a Drought, in the Neosho and Marais des Cygnes Rivers of Kansas
Deacon, James E.
397 Gutenberg downloadsen2010Difficulty 52 (Graduate)Hormones and Heredity A Discussion of the Evolution of Adaptations and the Evolution of Species
Cunningham, J. T. (Joseph Thomas)
397 Gutenberg downloadsen2005Difficulty 73 (Expert)Texas Honey Plants
Sanborn, Charles Emerson & Scholl, Ernest E. (Ernest Emmett)
396 Gutenberg downloadsen2012Difficulty 53 (Graduate)The Minor Horrors of War
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396 Gutenberg downloadsen2021Difficulty 51 (Graduate)The Speech of Monkeys
Garner, R. L. (Richard Lynch)
396 Gutenberg downloadsen2010Difficulty 54 (Graduate)The Underworld of Oregon Caves National Monument
Contor, Roger J.
396 Gutenberg downloadsen2019Difficulty 56 (Graduate)Unsere Haustiere vom Standpunkte ihrer wilden Verwandten
Zell, Th. (Theodor)
396 Gutenberg downloadsde2018International Weekly Miscellany of Literature, Art and Science — Volume 1, No. 2, July 8, 1850
Various
395 Gutenberg downloadsen2004Difficulty 59 (Graduate)The Dwelling House
Poore, George Vivian
395 Gutenberg downloadsen2015Difficulty 52 (Graduate)De la télépathie: Étude sur la transmission de la pensée
Hureau, Émile
394 Gutenberg downloadsfr2006Zoological Illustrations, Volume 3 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
394 Gutenberg downloadsen2012Difficulty 60 (Graduate)Evolution
Watson, James A. S. (James Anderson Scott)
393 Gutenberg downloadsen2016Difficulty 60 (Graduate)The Diatomaceæ of Philadelphia and Vicinity
Boyer, Charles S. (Charles Sumner)
393 Gutenberg downloadsen2014Difficulty 67 (Academic)Venomous arthropod handbook : $b envenomization symptoms/treatment, identification, biology and control
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393 Gutenberg downloadsen2018Difficulty 66 (Academic)The Philosophy of Health; Volume 1 (of 2) or, an exposition of the physical and mental constitution of man
Smith, Southwood
392 Gutenberg downloadsen2019Difficulty 73 (Expert)Two New Pocket Gophers from Wyoming and Colorado
Hall, E. Raymond (Eugene Raymond) & Montague, H. Gordon
392 Gutenberg downloadsen2009Difficulty 51 (Graduate)Ants and Some Other Insects: An Inquiry Into the Psychic Powers of These Animals
Forel, Auguste
391 Gutenberg downloadsen2016Difficulty 70 (Academic)Comments on the Taxonomy and Geographic Distribution of Some North American Rodents
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391 Gutenberg downloadsen2010Difficulty 56 (Graduate)The philosophy of biology
Johnstone, James
391 Gutenberg downloadsen2020Difficulty 65 (Academic)The Pocket Gophers (Genus Thomomys) of Utah University of Kansas Publications, Museum of Natural History, Vol. 1 No. 1
Durrant, Stephen David
391 Gutenberg downloadsen2012Difficulty 57 (Graduate)Whale Primer, with Special Attention to the California Gray Whale
Walker, Theodore J.
391 Gutenberg downloadsen2019Difficulty 55 (Graduate)A Bilateral Division of the Parietal Bone in a Chimpanzee; with a Special Reference to the Oblique Sutures in the Parietal
Hrdlička, Aleš
390 Gutenberg downloadsen2010Difficulty 65 (Academic)A Mechanico-Physiological Theory of Organic Evolution
Nägeli, Carl
390 Gutenberg downloadsen2010Difficulty 74 (Expert)An Annotated Check List of the Mammals of Michoacán, México
Hall, E. Raymond (Eugene Raymond) & Villa Ramírez, Bernardo
390 Gutenberg downloadsen2012Difficulty 55 (Graduate)Duality of Voice
Sutro, Emil
390 Gutenberg downloadsen2015Difficulty 63 (Academic)Het Leven der Dieren: Deel 1, Hoofdstuk 08: De Tandeloozen; Hoofdstuk 09: De Slurfdieren; Hoofdstuk 10: De Onevenvingerigen
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390 Gutenberg downloadsnl2007Le Sud-Oranais: études floristiques et phytogéographiques faites au cours d'une exploration dans le Sud-Ouest de l'Algérie en 1901
Hochreutiner, B. P. G. (Bénédict Pierre Georges)
390 Gutenberg downloadsfr2025The Toxicity of Caffein: An experimental study on different species of animals
Salant, William & Rieger, J. B. (John Benjamin)
390 Gutenberg downloadsen2014Difficulty 63 (Academic)The Vitamine Manual
Eddy, Walter Hollis
390 Gutenberg downloadsen2005Difficulty 58 (Graduate)Bedenkingen tegen de Leer van Darwin Gevolgd door beschouwingen over eenige philosophische onderwerpen.
Reuther, Antoine Charles
389 Gutenberg downloadsnl2009Die organische Chemie in ihrer Anwendung auf Physiologie und Pathologie
Liebig, Justus, Freiherr von
389 Gutenberg downloadsde2017Genera and Subgenera of Chipmunks
White, John A.
389 Gutenberg downloadsen2009Difficulty 61 (Academic)Illustrated Index of British Shells Containing figures of all the recent species
Sowerby, G. B. (George Brettingham)
389 Gutenberg downloadsen2013Difficulty 53 (Graduate)Life among the butterflies
Randolph, Vance
389 Gutenberg downloadsen2022Difficulty 56 (Graduate)Observations on the Mississippi Kite in Southwestern Kansas
Fitch, Henry S. (Henry Sheldon)
389 Gutenberg downloadsen2010Difficulty 55 (Graduate)Sertum Anglicum, seu, Plantae Rariores quae in Hortis Juxta Londinum Imprimis in Horto Regio Kewensi excoluntur, ab anno 1786 ad annum 1787 observata
L'Héritier de Brutelle, Charles Louis
389 Gutenberg downloadsla2012Some possible bearings of genetics on pathology
Morgan, Thomas Hunt
389 Gutenberg downloadsen2023Difficulty 57 (Graduate)Zoological Illustrations, Second Series, Volume 3 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
389 Gutenberg downloadsen2013Difficulty 61 (Academic)Essays on Darwinism
Stebbing, Thomas Roscoe Rede
388 Gutenberg downloadsen2015Difficulty 63 (Academic)Carlo Darwin
Lessona, Michele
387 Gutenberg downloadsit2014The flowering plants of South Africa; vol. 5
Pole Evans, I. B. (Illtyd Buller)
387 Gutenberg downloadsen2025Difficulty 50 (College)The modes of origin of lowest organisms including a discussion of the experiments of M. Pasteur
Bastian, H. Charlton
387 Gutenberg downloadsen2015Difficulty 71 (Expert)Comments on the Taxonomy and Geographic Distribution of North American Microtines
Hall, E. Raymond (Eugene Raymond) & Cockrum, E. Lendell
386 Gutenberg downloadsen2009Difficulty 62 (Academic)The works of Francis Maitland Balfour, Volume 4 (of 4) : $b Plates
Balfour, Francis M. (Francis Maitland)
386 Gutenberg downloadsen2014Difficulty 50 (College)A New Subspecies of Slider Turtle (Pseudemys scripta) from Coahuila, México
Legler, John M.
385 Gutenberg downloadsen2010Difficulty 60 (Graduate)Gorillas & Chimpanzees
Garner, R. L. (Richard Lynch)
385 Gutenberg downloadsen2013Difficulty 51 (Graduate)Den Waaragtigen Omloop des Bloeds
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384 Gutenberg downloadsnl2006Het Leven der Dieren, Deel 3, Hoofdstuk 6: De Wormen
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384 Gutenberg downloadsnl2020Het Leven der Dieren: Deel 2, Hoofdstuk 02: De Papegaaien; Hoofdstuk 03: De Duifvogels
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384 Gutenberg downloadsnl2009Notizie del pubblico giardino de' semplici di Padova compilate intorno l'anno 1771
Marsili, Giovanni
384 Gutenberg downloadsit2005Pleistocene Bats from San Josecito Cave, Nuevo Leon, Mexico
Jones, J. Knox
384 Gutenberg downloadsen2009Difficulty 55 (Graduate)Mammals of the San Gabriel Mountains of California
Vaughan, Terry A.
383 Gutenberg downloadsen2011Difficulty 63 (Academic)Phrenological Development of Robert Burns From a Cast of His Skull Moulded at Dumfries, the 31st Day of March 1834
Combe, George
383 Gutenberg downloadsen2009Difficulty 58 (Graduate)The American Bee Journal, Volume VI, Number 3, September 1870
Various
383 Gutenberg downloadsen2018Difficulty 56 (Graduate)The Baculum in Microtine Rodents
Anderson, Sydney
383 Gutenberg downloadsen2011Difficulty 65 (Academic)The flowering plants of South Africa; vol. 2
Unknown
383 Gutenberg downloadsen2021Difficulty 51 (Graduate)An Annotated Checklist of Nebraskan Bats
Webb, Olin L. & Jones, J. Knox
382 Gutenberg downloadsen2010Difficulty 55 (Graduate)Sanitation in Panama
Gorgas, William Crawford
382 Gutenberg downloadsen2023Difficulty 56 (Graduate)The human foot and the human hand
Humphry, George Murray, Sir
381 Gutenberg downloadsen2025Difficulty 48 (College)The plurality of the human race
Pouchet, G. (Georges)
381 Gutenberg downloadsen2023Difficulty 61 (Academic)Records of the Fossil Mammal Sinclairella, Family Apatemyidae, From the Chadronian and Orellan
Clemens, William A. (William Alvin)
380 Gutenberg downloadsen2009Difficulty 57 (Graduate)Seventeen Species of Bats Recorded from Barro Colorado Island, Panama Canal Zone
Hall, E. Raymond (Eugene Raymond) & Jackson, William B.
378 Gutenberg downloadsen2009Difficulty 48 (College)A New Genus of Pennsylvanian Fish (Crossopterygii, Coelacanthiformes) from Kansas
Echols, Joan
377 Gutenberg downloadsen2010Difficulty 60 (Graduate)Apes and Monkeys: Their Life and Language
Garner, R. L. (Richard Lynch)
377 Gutenberg downloadsen2022Difficulty 55 (Graduate)Description of a New Softshell Turtle from the Southeastern United States
Webb, Robert G. (Robert Gravem)
377 Gutenberg downloadsen2010Difficulty 60 (Graduate)Rudiments of Conchology Intended as a familiar introduction to the science.
Venning, Mary Anne
377 Gutenberg downloadsen2015Difficulty 49 (College)Fruits of the Hawaiian Islands
Wilder, Gerrit Parmile
376 Gutenberg downloadsen2013Difficulty 52 (Graduate)Graphic illustrations of abortion and the diseases of menstruation Consisting of Twelve Plates from Drawings Engraved on Stone, and Coloured by Mr. J. Perry, and Two Copper-plates from the Philosophical Transactions, Coloured by the Same Artist. the Whole Representing Forty-five Specimens of Aborted Ova and Adventitious Productions of the Uterus, With Preliminary Observations, Explanations of the Figures and Remarks, Anatomical and Physiological.
Granville, A. B. (Augustus Bozzi)
376 Gutenberg downloadsen2019Difficulty 61 (Academic)The Conchologist's First Book A System of Testaceous Malacology, Arranged Expressly for the Use of Schools, in Which the Animals, According to Cuvier, Are Given With the Shells, a Great Number of New Species Added, and the Whole Brought Up, as Accurately as Possible, to the Present Condition of the Science.
Poe, Edgar Allan & Brown, Thomas
376 Gutenberg downloadsen2021Difficulty 53 (Graduate)The octopus : $b or, The "devil-fish" of fiction and of fact
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376 Gutenberg downloadsen2023Difficulty 61 (Academic)Antony van Leeuwenhoek, de ontdekker der infusorien, 1675-1875
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375 Gutenberg downloadsnl2021El Campesino Puertorriqueño Sus Condiciones Físicas, Intelectuales y Morales, Causas que la Determinan y Medios Para Mejorarlas
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375 Gutenberg downloadses2015Lehrbuch der Toxikologie für Tierärzte
Fröhner, Eugen
375 Gutenberg downloadsde2022Phrenology Examined
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375 Gutenberg downloadsen2021Difficulty 59 (Graduate)The chocolate-plant (Theobroma cacao) and its products
Anonymous
375 Gutenberg downloadsen2025Difficulty 55 (Graduate)The Gospel of Evolution From "The Atheistic Platform", Twelve Lectures
Aveling, Edward B.
375 Gutenberg downloadsen2011Difficulty 55 (Graduate)All about Ferrets and Rats A Complete History of Ferrets, Rats, and Rat Extermination from Personal Experiences and Study. Also a Practical Hand-Book on the Ferret.
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374 Gutenberg downloadsen2013Difficulty 48 (College)Höherzüchtung des Menschen auf biologischer Grundlage. Vortrag
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374 Gutenberg downloadsde2013Last Words on Evolution: A Popular Retrospect and Summary
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374 Gutenberg downloadsen2016Difficulty 68 (Academic)Marxism and Darwinism : $b Evidence, speeches, and papers in its favour
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374 Gutenberg downloadsen2023Difficulty 58 (Graduate)The botanist's repository for new and rare plants; vol. 07 [of 10]
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374 Gutenberg downloadsen2024Difficulty 57 (Graduate)The fauna of the deep sea
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374 Gutenberg downloadsen2021Difficulty 63 (Academic)Het Leven der Dieren: Deel 3.7, De Weekdieren
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373 Gutenberg downloadsnl2020Zeugnisse für die Stellung des Menschen in der Natur
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373 Gutenberg downloadsde2010Bee-keeping for profit
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372 Gutenberg downloadsen2022Difficulty 53 (Graduate)Geographic Range of the Hooded Skunk, Mephitis macroura With Description of a New Subspecies from Mexico
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
372 Gutenberg downloadsen2010Difficulty 57 (Graduate)Journal of Entomology and Zoology, Vol. 09, No. 3, September 1917
Various
372 Gutenberg downloadsen2015Difficulty 56 (Graduate)Palm trees of the Amazon and their uses
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372 Gutenberg downloadsen2023Difficulty 62 (Academic)The English moths and butterflies : $b Together with the plants, flowers, and fruits whereon they feed, and are usually found.
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372 Gutenberg downloadsen2024Difficulty 58 (Graduate)Experiments and Observations Relative to the Influence Lately Discovered by M. Galvani and Commonly Called Animal Electricity
Fowler, Richard
371 Gutenberg downloadsen2014Difficulty 64 (Academic)Het Leven der Dieren: Deel 1, Hoofdstuk 12: Sirenen; Hoofdstuk 13: Walvischachtigen
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371 Gutenberg downloadsnl2007Additions to the List of the Birds of Louisiana
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370 Gutenberg downloadsen2010Difficulty 61 (Academic)Comments on the Taxonomy and Geographic Distribution of Some North American Rabbits
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370 Gutenberg downloadsen2009Difficulty 58 (Graduate)Descriptions of Two Species of Frogs, Genus Ptychohyla Studies of American Hylid Frogs, V
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370 Gutenberg downloadsen2010Difficulty 59 (Graduate)Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, III. Band Das Emporblühen der modernen Naturwissenschaften bis zur Entdeckung des Energieprinzipes
Dannemann, Friedrich
370 Gutenberg downloadsde2018Methods of Destroying Rats
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370 Gutenberg downloadsen2010Difficulty 55 (Graduate)Scientific American Supplement, No. 648, June 2, 1888.
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370 Gutenberg downloadsen2011Difficulty 54 (Graduate)The Botanical Magazine, Vol. 10 Or, Flower-Garden Displayed
Curtis, William
370 Gutenberg downloadsen2020Difficulty 57 (Graduate)The botanist's repository for new and rare plants; vol. 08 [of 10]
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370 Gutenberg downloadsen2024Difficulty 58 (Graduate)The Present Method of Inoculating for the Small-Pox To which are added, some experiments, instituted with a view to discover the effects of a similar treatment in the natural small-pox
Dimsdale, Thomas
370 Gutenberg downloadsen2015Difficulty 68 (Academic)A Statistical Inquiry Into the Nature and Treatment of Epilepsy
Bennett, Alexander Hughes
369 Gutenberg downloadsen2011Difficulty 44 (College)Saunders' Books on Pathology, Physiology Histology, Embryology and Bacteriology
W.B. Saunders Company
369 Gutenberg downloadsen2017Difficulty 61 (Academic)Species Plantarum, Sections XI-XIII
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369 Gutenberg downloadsla2010The botanist's repository for new and rare plants; vol. 09 [of 10]
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369 Gutenberg downloadsen2024Difficulty 55 (Graduate)The Migration of North American Birds (1935)
Lincoln, Frederick Charles
369 Gutenberg downloadsen2021Difficulty 71 (Expert)Het paddenstoelenboekje
Cool, Cath. (Catharina) & Lek, H. A. A. van der (Hendrik Adrianus Abraham)
368 Gutenberg downloadsnl2015Histoire naturelle des oiseaux d'Afrique, t. 1
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368 Gutenberg downloadsfr2018Home Range and Movements of the Eastern Cottontail in Kansas
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368 Gutenberg downloadsen2009Difficulty 55 (Graduate)Inorganic Plant Poisons and Stimulants
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368 Gutenberg downloadsen2015Difficulty 61 (Academic)La philosophie zoologique avant Darwin
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368 Gutenberg downloadsfr2010Mammals taken Along the Alaska Highway
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368 Gutenberg downloadsen2010Difficulty 47 (College)Meinauer Naturlehre
Unknown
368 Gutenberg downloadsde2009The Domestic Cat
Stables, Gordon
368 Gutenberg downloadsen2011Difficulty 51 (Graduate)The ethics of Hercules : $b A study of man's body as the sole determinant of ethical values
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368 Gutenberg downloadsen2023Difficulty 63 (Academic)Migration of Birds (1950)
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367 Gutenberg downloadsen2021Difficulty 70 (Academic)Morphological Variation in a Population of the Snake, Tantilla gracilis Baird and Girard
Hardy, Laurence M. & Cole, Charles J.
367 Gutenberg downloadsen2010Difficulty 55 (Graduate)Studies of Birds Killed in Nocturnal Migration
Tordoff, Harrison Bruce & Mengel, Robert Morrow
367 Gutenberg downloadsen2016Difficulty 54 (Graduate)Taxonomic Notes on Mexican Bats of the Genus Rhogeëssa
Hall, E. Raymond (Eugene Raymond)
367 Gutenberg downloadsen2010Difficulty 50 (College)Darwin, and After Darwin, Volume 3 of 3 Post-Darwinian Questions: Isolation and Physiological Selection
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366 Gutenberg downloadsen2011Difficulty 66 (Academic)Einheimische Fische; Die Süßwasserfische unsrer Heimat
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366 Gutenberg downloadsde2012Mushrooms of America, Edible and Poisonous
Unknown
366 Gutenberg downloadsen2009Difficulty 49 (College)Birds and Nature Vol. 09 No. 3 [March 1901]
Various
365 Gutenberg downloadsen2014Difficulty 54 (Graduate)Memoir on the Dodo (Didus ineptus, Linn.)
Owen, Richard
365 Gutenberg downloadsen2025Difficulty 57 (Graduate)Notes on Diseases of Swine, Sheep, Poultry and the Dog Cause, Symptoms and Treatments
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365 Gutenberg downloadsen2019Difficulty 55 (Graduate)Prodromus Florae Norfolkicae Sive, Catalogus stirpium quae in insula Norfolk annis 1804 et 1805 a Ferdinando Bauer collectae et depictae, nunc in Museo caesareo palatino rerum naturalium Vindobonae servantur
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365 Gutenberg downloadsla2012The Behavior of the Honey Bee in Pollen Collecting
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365 Gutenberg downloadsen2012Difficulty 54 (Graduate)The puzzle of life and how it has been put together : $b A short history of the formation of the earth, with its vegetable and animal life, from the earliest times, including an account of prehistoric man, his weapons, tools, and works
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365 Gutenberg downloadsen2025Difficulty 49 (College)Beautiful Ferns
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364 Gutenberg downloadsen2014Difficulty 58 (Graduate)Natural History of the Brush Mouse (Peromyscus boylii) in Kansas With Description of a New Subspecies
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364 Gutenberg downloadsen2010Difficulty 51 (Graduate)Plague Its Cause and the Manner of its Extension, Its Menace, Its Control and Suppression, Its Diagnosis and Treatment
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364 Gutenberg downloadsen2013Difficulty 68 (Academic)Five Natural Hybrid Combinations in Minnows (Cyprinidae)
Cross, Frank B. (Frank Bernard) & Minckley, W. L.
363 Gutenberg downloadsen2011Difficulty 55 (Graduate)Report on the Migration of Birds in the Spring and Autumn of 1881. Third Report
Harvie-Brown, J. A. (John Alexander) & Barrington, Richard Manliffe & Cordeaux, John & Kermode, P. M. C. (Philip Moore Callow) & More, Alexander Goodman
363 Gutenberg downloadsen2021Difficulty 41 (College)A New Subspecies of the Black Myotis (Bat) from Eastern Mexico
Hall, E. Raymond (Eugene Raymond) & Alvarez, Ticul
362 Gutenberg downloadsen2008Difficulty 55 (Graduate)De martelaars der wetenschap
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361 Gutenberg downloadsnl2018Little Wanderers
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361 Gutenberg downloadsen2020Difficulty 41 (College)The Coal Measures Amphibia of North America
Moodie, Roy Lee
361 Gutenberg downloadsen2019Difficulty 62 (Academic)The Kingdom of Man
Lankester, E. Ray (Edwin Ray), Sir
361 Gutenberg downloadsen2019Difficulty 61 (Academic)The Philosophy of Health; Volume 2 (of 2) or, an exposition of the physical and mental constitution of man
Smith, Southwood
361 Gutenberg downloadsen2019Difficulty 72 (Expert)A guide to the shell and starfish galleries : $b (Mollusca, Polyzoa, Brachiopoda, Tunicata, Echinoderma, and Worms)
British Museum (Natural History). Department of Zoology & Bell, F. J. (Francis Jeffrey) & Kirkpatrick, R. (Randolph) & Smith, E. A. (Edgar Albert)
360 Gutenberg downloadsen2024Difficulty 59 (Graduate)Self-Organizing Systems, 1963
Unknown
360 Gutenberg downloadsen2021Difficulty 72 (Expert)An inaugural dissertation on pulmonary consumption
Delafield, Edward
359 Gutenberg downloadsen2022Difficulty 63 (Academic)Bacteria in Daily Life
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359 Gutenberg downloadsen2013Difficulty 81 (Specialist)Die Zelle
Kahn, Fritz
359 Gutenberg downloadsde2012The Anatomy of Vegetables Begun With a General Account of Vegetation founded thereon
Grew, Nehemiah
359 Gutenberg downloadsen2018Difficulty 48 (College)A Taxonomic Revision of the Leptodactylid Frog Genus Syrrhophus Cope
Lynch, John D.
358 Gutenberg downloadsen2011Difficulty 64 (Academic)Careers in Atomic Energy
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358 Gutenberg downloadsen2013Difficulty 68 (Academic)Das Mikroskop und seine Anwendung Ein Leitfaden bei mikroskopischen Untersuchungen
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358 Gutenberg downloadsde2015Het Leven der Dieren: Hoofdstuk 7: De Pluviervogels
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358 Gutenberg downloadsnl2010A New Bog Lemming (Genus Synaptomys) From Nebraska
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357 Gutenberg downloadsen2010Difficulty 62 (Academic)Fossil Butterflies Memoirs of the American Association for the Advancement of Science, I.
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357 Gutenberg downloadsen2017Difficulty 59 (Graduate)Het Leven der Dieren: Deel 3.8, De Stekelhuidigen, Plantdieren en Sponsen
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357 Gutenberg downloadsnl2020The Kansas University Quarterly, Vol. I, No. 1 (1892)
Various
357 Gutenberg downloadsen2017Difficulty 58 (Graduate)The Microscope
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357 Gutenberg downloadsen2013Difficulty 65 (Academic)Thoracic and Coracoid Arteries In Two Families of Birds, Columbidae and Hirundinidae
Jenkinson, Marion Anne
357 Gutenberg downloadsen2010Difficulty 64 (Academic)A New Name for the Mexican Red Bat
Hall, E. Raymond (Eugene Raymond)
356 Gutenberg downloadsen2007Difficulty 55 (Graduate)Breves instrucções aos correspondentes da Academia das Sciencias de Lisboa sobre as remessas dos productos, e noticias pertencentes a' Historia da Natureza, para formar hum Museo Nacional
Unknown
356 Gutenberg downloadspt2005A New Bat (Myotis) From Mexico
Hall, E. Raymond (Eugene Raymond)
355 Gutenberg downloadsen2010Difficulty 57 (Graduate)Comments on the Taxonomic Status of Apodemus peninsulae, with Description of a New Subspecies from North China
Jones, J. Knox
355 Gutenberg downloadsen2010Difficulty 62 (Academic)Degeneration: A Chapter in Darwinism
Lankester, E. Ray (Edwin Ray), Sir
355 Gutenberg downloadsen2019Difficulty 66 (Academic)Het Leven der Dieren: Deel 1, Hoofdstuk 02: De Halfapen; Hoofdstuk 03: De Vleermuizen
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355 Gutenberg downloadsnl2005On the Variation of Species, with Especial Reference to the Insecta Followed by an Inquiry into the Nature of Genera
Wollaston, Thomas Vernon
355 Gutenberg downloadsen2012Difficulty 78 (Expert)Type specimens of amphibians and reptiles in the Museum of Natural History, the University of Kansas
Duellman, William Edward & Berg, Barbara
355 Gutenberg downloadsen2024Difficulty 56 (Graduate)Vasárnapi Könyv. 1914. Első félév 15. füzet
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355 Gutenberg downloadshu2009Der Mensch der Zukunft
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354 Gutenberg downloadsde2018The Subspecies of the Mexican Red-Bellied Squirrel, Sciurus aureogaster
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354 Gutenberg downloadsen2010Difficulty 61 (Academic)Evolution Social and Organic
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353 Gutenberg downloadsen2018Difficulty 57 (Graduate)Het Leven der Dieren: Deel 2, Hoofdstuk 05: De Ralvogels; Hoofdstuk 06: De Kraanvogels
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353 Gutenberg downloadsnl2009Poisonous Dwellers of the Desert
Dodge, Natt N. (Natt Noyes)
353 Gutenberg downloadsen2017Difficulty 61 (Academic)Race Improvement; or, Eugenics: A Little Book on a Great Subject
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353 Gutenberg downloadsen2015Difficulty 63 (Academic)Roses: or, a Monograph of the Genus Rosa
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353 Gutenberg downloadsen2021Difficulty 63 (Academic)The apiary; or, bees, bee-hives, and bee culture [1866] Being a familiar account of the habits of bees, and the most improved methods of management, with full directions, adapted for the cottager, farmer, or scientific apiarian
Neighbor, Alfred
353 Gutenberg downloadsen2022Difficulty 59 (Graduate)De afstamming van den mensch Naar voordrachten in populair-wetenschappelijken vorm bewerkt
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352 Gutenberg downloadsnl2017Emanuel Swedenborg's Investigations in Natural Science and the Basis for His Statements Concerning the Functions of the Brain
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352 Gutenberg downloadsen2020Difficulty 71 (Expert)Sciências Naturaes Pela Redacção da «Educação Nacional»
Anonymous
352 Gutenberg downloadspt2006De honig en zijn gebruik
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351 Gutenberg downloadsnl2008Pliocene and Pleistocene Records of Fossil Turtles from Western Kansas and Oklahoma University of Kansas Publications Museum of Natural History Volume 1
Galbreath, Edwin C. (Edwin Carter)
351 Gutenberg downloadsen2010Difficulty 60 (Graduate)Section Cutting and Staining A practical introduction to histological methods for students and practitioners
Colman, Walter S.
351 Gutenberg downloadsen2016Difficulty 50 (College)The Meaning of Infancy
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351 Gutenberg downloadsen2004Difficulty 62 (Academic)The preparation & mounting of microscopic objects
Davies, Thomas
351 Gutenberg downloadsen2019Difficulty 53 (Graduate)Het Leven der Dieren: Deel 1, Hoofdstuk 14: Buideldieren; Hoofdstuk 15: Kloakdieren
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350 Gutenberg downloadsnl2007Nests and Eggs of Familiar British Birds, Second Series Described and Illustrated; with an Account of the Haunts and Habits of the Feathered Architects, and their Times and Modes of Building
Adams, H. G. (Henry Gardiner)
350 Gutenberg downloadsen2012Difficulty 60 (Graduate)Notes on Veterinary Anatomy
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350 Gutenberg downloadsen2019Difficulty 53 (Graduate)The American Bee Journal, Vol. VI., Number 5, November 1870
Various
350 Gutenberg downloadsen2018Difficulty 53 (Graduate)Bee Keeping
Benton, Frank
349 Gutenberg downloadsen2015Difficulty 63 (Academic)Coyotes in Their Economic Relations
Lantz, David E. (David Ernest)
349 Gutenberg downloadsen2014Difficulty 54 (Graduate)Der Tabak: Studien über seine Kultur und Biologie
Koning, C. J. (Cornelis Johan)
348 Gutenberg downloadsde2016Report on the Migration of Birds in the Spring and Autumn of 1886. Eighth Report (Vol. II, No. 3.)
Harvie-Brown, J. A. (John Alexander) & Barrington, Richard Manliffe & Clarke, William Eagle & Cordeaux, John & More, Alexander Goodman
348 Gutenberg downloadsen2021Difficulty 43 (College)The Ornithosauria An elementary study of the bones of Pterodactyles made from fossil remains found in the Cambridge Upper Greensand, and arranged in the Woodwardian Museum of the University of Cambridge
Seeley, H. G. (Harry Govier)
348 Gutenberg downloadsen2016Difficulty 58 (Graduate)Descriptive Zoopraxography; or, the science of animal locomotion made popular
Muybridge, Eadweard
347 Gutenberg downloadsen2012Difficulty 72 (Expert)Foreign Butterflies
Duncan, James
347 Gutenberg downloadsen2018Difficulty 56 (Graduate)A New Subspecies of Microtus montanus from Montana and Comments on Microtus canicaudus Miller
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346 Gutenberg downloadsen2009Difficulty 58 (Graduate)Ameboid movement
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346 Gutenberg downloadsen2017Difficulty 66 (Academic)Cruise of the Revenue-Steamer Corwin in Alaska and the N.W. Arctic Ocean in 1881: Botanical Notes Notes and Memoranda: Medical and Anthropological; Botanical; Ornithological.
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346 Gutenberg downloadsen2010Difficulty 54 (Graduate)Het Leven der Dieren: Deel 1, Hoofdstuk 05: Robben; Hoofdstuk 06: Insecteneters
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346 Gutenberg downloadsnl2006Journal of Entomology and Zoology, Vol. 11, No. 1, March 1919
Various
346 Gutenberg downloadsen2014Difficulty 62 (Academic)The Birds of Australia, Vol. 3 of 7
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346 Gutenberg downloadsen2019Difficulty 61 (Academic)Adequate Preparation for the Teacher of Biological Sciences in Secondary Schools
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345 Gutenberg downloadsen2010Difficulty 64 (Academic)Notes on Philippine Birds Collected by Governor W. Cameron Forbes Bulletin of the Museum of Comparative Zoölogy at Harvard College, Vol. LXV. No. 4.
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345 Gutenberg downloadsen2011Difficulty 49 (College)Proceedings of the California Academy of Sciences, Series 3, Volume 4 (Zoology)
Various
345 Gutenberg downloadsen2017Difficulty 70 (Academic)The Story of Germ Life
Conn, H. W. (Herbert William)
345 Gutenberg downloadsen2004Difficulty 60 (Graduate)The giant sequoia : $b An account of the history and characteristics of the big trees of California
Ellsworth, Rodney Sydes
344 Gutenberg downloadsen2025Difficulty 56 (Graduate)Water Reptiles of the Past and Present
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344 Gutenberg downloadsen2022Difficulty 63 (Academic)Subspeciation in the Meadow Mouse, Microtus montanus, in Wyoming and Colorado
Anderson, Sydney
343 Gutenberg downloadsen2010Difficulty 50 (College)A Synopsis of the British Mosses Containing Descriptions of All the Genera and Species, (With Localities of the Rarer Ones) Found in Great Britain and Ireland, Based Upon Wilson's "Bryologia Britannica," Schimper's "Synopsis," Etc.
Hobkirk, Charles C. P. (Charles Codrington Pressick)
342 Gutenberg downloadsen2021Difficulty 63 (Academic)Report on the Migration of Birds in the Spring and Autumn of 1883. Fifth Report
Harvie-Brown, J. A. (John Alexander) & Barrington, Richard Manliffe & Cordeaux, John & More, Alexander Goodman
342 Gutenberg downloadsen2021Difficulty 44 (College)The Factors of Organic Evolution
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342 Gutenberg downloadsen2016Difficulty 70 (Academic)Über den Bildungstrieb
Blumenbach, Johann Friedrich
342 Gutenberg downloadsde2020De Usu Ratiocinii Mechanici in Medicina
Boerhaave, Herman
341 Gutenberg downloadsla2005Descripção de algumas especies novas ou pouco conhecidas de crustaceos e arachnidios de Portugal e possessões portuguezas do ultramar
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341 Gutenberg downloadsfr2010Researches on the Visual Organs of the Trilobites
Lindström, Gustaf
340 Gutenberg downloadsen2022Difficulty 54 (Graduate)Section-Cutting A Practical Guide to the Preparation and Mounting of Sections for the Microscope, Special Prominence Being given to the Subject of Animal Sections
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340 Gutenberg downloadsen2017Difficulty 61 (Academic)La flore utile du bassin de la Gambie
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339 Gutenberg downloadsfr2024Supplement to Harvesting Ants and Trap-Door Spiders
Moggridge, John Traherne & Pickard-Cambridge, Octavius
339 Gutenberg downloadsen2021Difficulty 59 (Graduate)The Christian Foundation, Or, Scientific and Religious Journal, Volume 1, Index, 1880
Various
339 Gutenberg downloadsen2009Difficulty 77 (Expert)The heathery; or, A monograph of the genus Erica. vol. 4
Andrews, Henry Cranke, active 1799-1828
339 Gutenberg downloadsen2023Difficulty 56 (Graduate)The Hunterian lectures on colour-vision and colour-blindness
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339 Gutenberg downloadsen2025Difficulty 56 (Graduate)The O. S. U. Naturalist, Vol. 1, No. 1, November, 1900
Ohio State University. Biological Club
339 Gutenberg downloadsen2017Difficulty 56 (Graduate)The Rocky Mountain Goat
Grant, Madison
339 Gutenberg downloadsen2015Difficulty 57 (Graduate)Use of the Dead to the Living
Smith, Southwood
339 Gutenberg downloadsen2018Difficulty 67 (Academic)Sir William Flower
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338 Gutenberg downloadsen2025Difficulty 72 (Expert)Studies in Spermatogenesis (Part 1 of 2)
Stevens, N. M. (Nettie Maria)
338 Gutenberg downloadsen2010Difficulty 57 (Graduate)The Sense of Taste
Hollingworth, Harry L. (Harry Levi) & Poffenberger, Albert T. (Albert Theodore)
338 Gutenberg downloadsen2019Difficulty 69 (Academic)A mechanical and critical enquiry into the nature of hermaphrodites
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337 Gutenberg downloadsen2023Difficulty 62 (Academic)A New Hylid Frog from Eastern Mexico. University of Kansas Publication, Vol 1, No 15
Taylor, Edward Harrison
337 Gutenberg downloadsen2010Difficulty 62 (Academic)Food of the Crow, Corvus brachyrhynchos Brehm, in South-central Kansas
Platt, Dwight R.
337 Gutenberg downloadsen2010Difficulty 53 (Graduate)On the origin of inflammation of the veins and of the causes, consequences, and treatment of purulent deposits
Lee, Henry, M.D.
337 Gutenberg downloadsen2014Difficulty 65 (Academic)Schenk's Theory: The Determination of Sex
Schenk, Samuel Leopold
337 Gutenberg downloadsen2014Difficulty 59 (Graduate)The botanist's repository for new and rare plants; vol. 06 [of 10]
Andrews, Henry Cranke, active 1799-1828
337 Gutenberg downloadsen2024Difficulty 63 (Academic)The Nautilus. Vol. XXXI, No. 2, October 1917 A Quarterly Journal Devoted to the Interests of Conchologists
Various
337 Gutenberg downloadsen2019Difficulty 52 (Graduate)The Atom and the Ocean
Hull, E. W. Seabrook
336 Gutenberg downloadsen2021Difficulty 61 (Academic)The House We Live In; or, The Making of the Body
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336 Gutenberg downloadsen2021Difficulty 31 (High School)The Ohio naturalist, Vol. 1, No. 4, February 1901
Ohio State University. Biological Club
336 Gutenberg downloadsen2022Difficulty 49 (College)Educação nova: As bases
Alves dos Santos, Augusto Joaquim
335 Gutenberg downloadspt2012Mammals of the Grand Mesa, Colorado
Anderson, Sydney
335 Gutenberg downloadsen2010Difficulty 51 (Graduate)Reise in die Aequinoctial-Gegenden des neuen Continents. Band 4.
Humboldt, Alexander von
335 Gutenberg downloadsde2012Report on the Migration of Birds in the Autumn of 1879. [First Report]
Harvie-Brown, J. A. (John Alexander) & Cordeaux, John
335 Gutenberg downloadsen2021Difficulty 40 (High School)Arabische Pflanzennamen aus Aegypten, Algerien und Jemen
Schweinfurth, Georg August
334 Gutenberg downloadsde2024The Philosophy of Evolution Together With a Preliminary Essay on The Metaphysical Basis of Science
Carpenter, Stephen H. (Stephen Haskins)
334 Gutenberg downloadsen2009Difficulty 64 (Academic)Muistelmia hyönteismaailmasta: Kuvauksia hyönteisten tavoista ja vaistosta
Fabre, Jean-Henri
333 Gutenberg downloadsfi2021Proefnemingen van de particuliere beweeging der spieren in de kikvorsch
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333 Gutenberg downloadsnl2006A New Doglike Carnivore, Genus Cynarctus, From the Clarendonian, Pliocene, of Texas
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
332 Gutenberg downloadsen2009Difficulty 53 (Graduate)Relics of Primeval Life: Beginning of Life in the Dawn of Geological Time
Dawson, John William, Sir
332 Gutenberg downloadsen2022Difficulty 58 (Graduate)A New Pocket Mouse (Genus Perognathus) from Kansas
Cockrum, E. Lendell
331 Gutenberg downloadsen2010Difficulty 51 (Graduate)Palæontological Report of the Princeton Scientific Expedition of 1877
Osborn, Henry Fairfield & Scott, William Berryman & Speir, Francis
331 Gutenberg downloadsen2021Difficulty 56 (Graduate)Profitable poultry : $b Their management in health and disease
Tegetmeier, W. B. (William Bernhard)
331 Gutenberg downloadsen2024Difficulty 65 (Academic)The pathology of influenza
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331 Gutenberg downloadsen2019Difficulty 69 (Academic)The Structure and Habits of Spiders
Emerton, J. H. (James Henry)
331 Gutenberg downloadsen2018Difficulty 44 (College)A Monograph of Odontoglossum
Bateman, Jas. (James)
330 Gutenberg downloadsen2014Difficulty 61 (Academic)Biology versus Theology. The Bible: irreconcilable with Science, Experience, and even its own statements
Julian
330 Gutenberg downloadsen2021Difficulty 52 (Graduate)De Rariorum Animalium atque Stirpium Historia
Caius, John
330 Gutenberg downloadsla2008Geographic Variation in the Harvest Mouse, Reithrodontomys megalotis, On the Central Great Plains And in Adjacent Regions
Jones, J. Knox & Mursaloglu, B.
330 Gutenberg downloadsen2009Difficulty 56 (Graduate)The History of Esculent Fish
North, Roger
330 Gutenberg downloadsen2021Difficulty 47 (College)The Philosophy Which Shows the Physiology of Mesmerism and Explains the Phenomenon of Clairvoyance
Pasley, T. H.
330 Gutenberg downloadsen2015Difficulty 74 (Expert)Colour vision : $b Being the Tyndall Lectures delivered in 1894 at the Royal Institution
Abney, William de Wiveleslie, Sir
329 Gutenberg downloadsen2024Difficulty 55 (Graduate)Im Zauber des Tierlebens
Lucanus, Friedrich von
329 Gutenberg downloadsde2024Insect manufactures
Anonymous
329 Gutenberg downloadsen2024Difficulty 60 (Graduate)Selected Records of Reptiles and Amphibians from Kansas
Breukelman, John & Smith, Hobart M. (Hobart Muir)
329 Gutenberg downloadsen2010Difficulty 47 (College)Suomen maan Meripedot: maalikuvilla selitetyt
Eurén, Gustaf Erik
329 Gutenberg downloadsfi2005A New Subspecies of the Fruit-eating Bat, Sturnira ludovici, From Western Mexico
Jones, J. Knox & Phillips, Gary L.
328 Gutenberg downloadsen2010Difficulty 55 (Graduate)New West Indian Spiders Bulletin of the AMNH, Vol. XXXIII, Art. XLI, pp. 639-642
Banks, Nathan
327 Gutenberg downloadsen2010Difficulty 47 (College)Pflanzenleben in Feld und Garten
Buckley, Arabella B. (Arabella Burton)
327 Gutenberg downloadsde2022Rapport sur une mission botanique exécutée en 1884 dans le nord, le sud et l'ouest de la Tunisie
Letourneux, A. (Aristide)
327 Gutenberg downloadsfr2024The Postnatal Development of Two Broods of Great Horned Owls (Bubo virginianus)
Hoffmeister, Donald Frederick & Setzer, Henry W.
327 Gutenberg downloadsen2011Difficulty 51 (Graduate)The Science of Animal Locomotion (Zoopraxography) An Electro-Photographic Investigation of Consecutive Phases of Animal Movements
Muybridge, Eadweard
327 Gutenberg downloadsen2012Difficulty 64 (Academic)A New Piñon Mouse (Peromyscus truei) from Durango, Mexico
Finley, Robert B.
326 Gutenberg downloadsen2010Difficulty 57 (Graduate)Subspeciation in the Meadow Mouse, Microtus pennsylvanicus, in Wyoming, Colorado, and Adjacent Areas
Anderson, Sydney
326 Gutenberg downloadsen2010Difficulty 61 (Academic)Tentamen Botanicum de Filicum Generibus Dorsiferarum Mémoires de l'Académie Royale des Sciences de Turin vol. 5, 401-422
Smith, James Edward
326 Gutenberg downloadsla2012The Baculum in the Chipmunks of Western North America
White, John A.
326 Gutenberg downloadsen2010Difficulty 46 (College)A New Long-eared Myotis (Myotis evotis) From Northeastern Mexico
Baker, Rollin H. (Rollin Harold) & Stains, Howard J.
325 Gutenberg downloadsen2010Difficulty 54 (Graduate)Death and resurrection from the point of view of the cell-theory
Björklund, Gustaf
325 Gutenberg downloadsen2019Difficulty 58 (Graduate)Humanity to Honey-Bees or, Practical Directions for the Management of Honey-Bees Upon an Improved and Humane Plan, by Which the Lives of Bees May Be Preserved, and Abundance of Honey of a Superior Quality May Be Obtained
Nutt, Thomas
325 Gutenberg downloadsen2018Difficulty 65 (Academic)The Italian Alp-bee; or, The gold mine of husbandry short and practical instructions to breed genuine prolific Italian queens; to multiply them by hundreds in a few months and how to change German hives into Italian
Hermann, H. C. (Heinrich C.)
325 Gutenberg downloadsen2023Difficulty 51 (Graduate)The Mammals of Warren Woods, Berrien County, Michigan Occasional Paper of the Museum of Zoology, Number 86
Dice, Lee R. (Lee Raymond)
325 Gutenberg downloadsen2010Difficulty 49 (College)A New Species of Heteromyid Rodent from the Middle Oligocene of Northeast Colorado with Remarks on the Skull
Galbreath, Edwin C. (Edwin Carter)
324 Gutenberg downloadsen2010Difficulty 57 (Graduate)Atlas de poche des mammifères de la France, de la Suisse romane et de la Belgique avec leur description, moeurs et organisation
Martin, René
324 Gutenberg downloadsfr2017Het Leven der Dieren. Deel 3, Hoofdstuk 5: De Amphibiën
Brehm, Alfred Edmund
324 Gutenberg downloadsnl2014Natural History of the Salamander, Aneides hardii
Johnston, Richard F. & Schad, G. A.
324 Gutenberg downloadsen2010Difficulty 59 (Graduate)The Book of Shells Containing the Classes Mollusca, Conchifera, Cirrhipeda, Annulata, and Crustacea
Society for Promoting Christian Knowledge (Great Britain). Committee of General Literature and Education
324 Gutenberg downloadsen2019Difficulty 64 (Academic)Archimedes; or, the future of physics
Whyte, Lancelot Law
323 Gutenberg downloadsen2025Difficulty 66 (Academic)Jelly-Fish, Star-Fish, and Sea-Urchins: Being a Research on Primitive Nervous Systems
Romanes, George John
323 Gutenberg downloadsen2014Difficulty 64 (Academic)The run
Hay, John
323 Gutenberg downloadsen2025Difficulty 48 (College)A New Subspecies of Pocket Mouse from Kansas
Hall, E. Raymond (Eugene Raymond)
322 Gutenberg downloadsen2010Difficulty 57 (Graduate)The cretaceous birds of New Jersey
Olson, Storrs L. & Parris, David C.
322 Gutenberg downloadsen2022Difficulty 69 (Academic)De Harmonie van het Dierlijke Leven: De Openbaring van Wetten
Donders, F. C. (Franciscus Cornelis)
321 Gutenberg downloadsnl2005Description of a New Vespertilionine Bat from Yucatan Author's Edition, extracted from Bulletin of the American Museum of Natural History, Vol. IX, September 28, 1897
Allen, J. A. (Joel Asaph)
321 Gutenberg downloadsen2008Difficulty 53 (Graduate)Beautiful shells : $b Their nature, structure, and uses familiarly explained; with directions for collecting, cleaning, and arranging them in the cabinet; descriptions of the most remarkable species, and of the creatures which inhabit them; and explanations of the meanings of their scientific names, and of the terms used in conchology
Adams, H. G. (Henry Gardiner)
320 Gutenberg downloadsen2024Difficulty 66 (Academic)Geographic Distribution and Taxonomy of the Chipmunks of Wyoming
White, John A.
320 Gutenberg downloadsen2010Difficulty 50 (College)Het Leven der Dieren: Hoofdstuk 8: De Vinduikers; Hoofdstuk 9: de Stormvogels
Brehm, Alfred Edmund
320 Gutenberg downloadsnl2010Fishes of the Wakarusa River in Kansas
Deacon, James E. & Metcalf, Artie L.
319 Gutenberg downloadsen2010Difficulty 45 (College)Jaundice: Its Pathology and Treatment With the Application of Physiological Chemistry to the Detection and Treatment of Diseases of the Liver and Pancreas
Harley, George
319 Gutenberg downloadsen2015Difficulty 69 (Academic)The suppression of tuberculosis $b Together with observations concerning phthisiogenesis in man and animals and suggestions concerning the hygiene of cow stables and the production of milk for infant-feeding, with special reference to tuberculosis
Behring, Emil von
319 Gutenberg downloadsen2023Difficulty 67 (Academic)Treatise on the Anatomy and Physiology of the Mucous Membranes With Illustrative Pathological Observations
Bichat, Xavier
319 Gutenberg downloadsen2016Difficulty 67 (Academic)A Monograph of the Trilobites of North America: with Coloured Models of the Species
Green, Jacob
318 Gutenberg downloadsen2021Difficulty 63 (Academic)Fauna der Nassauischen Mollusken
Kobelt, Wilhelm
318 Gutenberg downloadsde2015Natural History of the Bell Vireo, Vireo bellii Audubon
Barlow, Jon C.
318 Gutenberg downloadsen2010Difficulty 59 (Graduate)A bacteriological study of ham souring
McBryde, Charles Neil
317 Gutenberg downloadsen2022Difficulty 59 (Graduate)Two New Pelycosaurs from the Lower Permian of Oklahoma
Fox, Richard C.
317 Gutenberg downloadsen2009Difficulty 59 (Graduate)Poisonous Snakes of Kansas
Clarke, Robert F. (Robert Francis)
316 Gutenberg downloadsen2019Difficulty 50 (College)A New Tortoise, Genus Gopherus, From North-central Mexico
Legler, John M.
315 Gutenberg downloadsen2010Difficulty 62 (Academic)Cholera and the Water Supply in the South Districts of London in 1854
Snow, John
315 Gutenberg downloadsen2021Difficulty 71 (Expert)Field Mice as Farm and Orchard Pests
Lantz, David E. (David Ernest)
314 Gutenberg downloadsen2013Difficulty 54 (Graduate)Pipistrellus cinnamomeus Miller 1902 Referred to the Genus Myotis
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
314 Gutenberg downloadsen2010Difficulty 55 (Graduate)Μικρά Φυσικά, Τόμος Δεύτερος
Aristotle
314 Gutenberg downloadsel2009Biological analogies in history
Roosevelt, Theodore
313 Gutenberg downloadsen2023Difficulty 70 (Academic)The heathery; or, A monograph of the genus Erica. vol. 1
Andrews, Henry Cranke, active 1799-1828
313 Gutenberg downloadsen2022Difficulty 52 (Graduate)The heathery; or, A monograph of the genus Erica. vol. 3
Andrews, Henry Cranke, active 1799-1828
313 Gutenberg downloadsen2023Difficulty 56 (Graduate)A New Snake of the Genus Geophis From Chihuahua, Mexico
Legler, John M.
312 Gutenberg downloadsen2010Difficulty 63 (Academic)Carpet Beetles and Their Control
Back, E. A. (Ernest Adna)
312 Gutenberg downloadsen2019Difficulty 55 (Graduate)Rapport sur une mission botanique exécutée en 1884 dans la région saharienne, au nord des grands chotts et dans les îles de la côte orientale de la Tunisie
Doumet-Adanson, Napoléon
312 Gutenberg downloadsfr2024A Guide for the Dissection of the Dogfish (Squalus Acanthias)
Griffin, Lawrence Edmonds
311 Gutenberg downloadsen2019Difficulty 54 (Graduate)Bird studies with a camera : $b with introductory chapters on the outfit and methods of the bird photographer
Chapman, Frank M. (Frank Michler)
311 Gutenberg downloadsen2025Difficulty 50 (College)Journal of Entomology and Zoology, Vol. 06, No. 4, December 1914
Various
311 Gutenberg downloadsen2015Difficulty 53 (Graduate)Observations on the Terataspis grandis, Hall, the largest known trilobite
Clarke, John Mason
311 Gutenberg downloadsen2022Difficulty 60 (Graduate)A history of evolution
Fenton, Carroll Lane
310 Gutenberg downloadsen2025Difficulty 63 (Academic)A New Pocket Gopher (Thomomys) and A New Spiny Pocket Mouse (Liomys) from Michoacán, Mexico
Hall, E. Raymond (Eugene Raymond) & Villa Ramírez, Bernardo
310 Gutenberg downloadsen2010Difficulty 60 (Graduate)A New Subspecies of Bat (Myotis velifer) from Southeastern California and Arizona
Vaughan, Terry A.
310 Gutenberg downloadsen2010Difficulty 56 (Graduate)Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado
Douglas, Charles L.
310 Gutenberg downloadsen2012Difficulty 63 (Academic)Conspecificity of two pocket mice, Perognathus goldmani and P. artus
Hall, E. Raymond (Eugene Raymond) & Ogilvie, Marilyn Bailey
310 Gutenberg downloadsen2010Difficulty 52 (Graduate)A New Subspecies of Wood Rat (Neotoma mexicana) from Colorado
Finley, Robert B.
309 Gutenberg downloadsen2010Difficulty 60 (Graduate)Dissertatio inauguralis physico-medica de respiratione quam consensu & auctoritate gratiosissimi medicorum ordinis in universitate patria pro summis in arte medica honoribus & privilegiis doctoralibus rite consequendis....
Bernoulli, Daniel
309 Gutenberg downloadsla2013Geographic Variation in the Pocket Gopher, Thomomys bottae, in Colorado
Youngman, Phillip M.
309 Gutenberg downloadsen2011Difficulty 57 (Graduate)Het Leven der Dieren: Deel 2, Hoofdstuk 10: De Stootvogels
Brehm, Alfred Edmund
309 Gutenberg downloadsnl2012The Botanical Magazine, Vol. 09 Or, Flower-Garden Displayed
Curtis, William
309 Gutenberg downloadsen2011Difficulty 58 (Graduate)Geographic Variation in the Pocket Gopher, Cratogeomys castanops, in Coahuila, México
Russell, Robert J. & Baker, Rollin H. (Rollin Harold)
308 Gutenberg downloadsen2010Difficulty 64 (Academic)The Cubomedusæ
Conant, Franklin Story
308 Gutenberg downloadsen2017Difficulty 60 (Graduate)Alpine flora of the Canadian Rocky Mountains
Brown, Stewardson
307 Gutenberg downloadsen2025Difficulty 60 (Graduate)Coloured engravings of heaths; vol. 3
Andrews, Henry Cranke, active 1799-1828
307 Gutenberg downloadsen2023Difficulty 66 (Academic)Ilex cassine, the aboriginal North American tea $b Its history, distribution, and use among the native North American Indians
Hale, Edwin M. (Edwin Moses)
307 Gutenberg downloadsen2023Difficulty 52 (Graduate)Coloured engravings of heaths; vol. 4
Andrews, Henry Cranke, active 1799-1828
306 Gutenberg downloadsen2023Difficulty 60 (Graduate)Geographic Variation in Red-backed Mice (Genus Clethrionomys) of the Southern Rocky Mountain Region
Cockrum, E. Lendell & Fitch, Kenneth Leonard
306 Gutenberg downloadsen2010Difficulty 53 (Graduate)Links With the Past in the Plant World
Seward, A. C. (Albert Charles)
306 Gutenberg downloadsen2020Difficulty 65 (Academic)Piebald rats and selection : $b An experimental test of the effectiveness of selection and of the theory of gametic purity in Mendelian crosses
Castle, William E. (William Ernest) & Phillips, John C. (John Charles)
306 Gutenberg downloadsen2024Difficulty 54 (Graduate)The Ohio naturalist, Vol. 1, No. 8, June 1901
Ohio State University. Biological Club
306 Gutenberg downloadsen2022Difficulty 51 (Graduate)Aus Natur und Geisteswelt Sammlung wissenschaftlich-gemeinverständlicher Darstellungen aus allen Gebieten des Wissens
B.G. Teubner (Firm)
305 Gutenberg downloadsde2016Disease in captive wild mammals and birds : $b incidence, description, comparison
Fox, Herbert
305 Gutenberg downloadsen2025Difficulty 55 (Graduate)The Bedbug [1934]
Marlatt, C. L.
305 Gutenberg downloadsen2020Difficulty 62 (Academic)Ecology of the Opossum on a Natural Area in Northeastern Kansas
Fitch, Henry S. (Henry Sheldon) & Sandidge, Lewis L.
304 Gutenberg downloadsen2011Difficulty 62 (Academic)Leprosy : $b in its clinical & pathological aspects
Hansen, G. Armauer (Gerhard Armauer) & Looft, Carl
304 Gutenberg downloadsen2023Difficulty 64 (Academic)Meeresfische
Floericke, Kurt
304 Gutenberg downloadsde2018Practical Skunk Raising A Book of Information Concerning the Raising of Skunks for Profit
Pratt, William Edwin
304 Gutenberg downloadsen2014Difficulty 40 (High School)Studies in Spermatogenesis (Part 2 of 2)
Stevens, N. M. (Nettie Maria)
304 Gutenberg downloadsen2010Difficulty 58 (Graduate)A New Bat (Genus Leptonycteris) From Coahuila
Stains, Howard J.
303 Gutenberg downloadsen2010Difficulty 53 (Graduate)Genera of Leptodactylid Frogs in México
Lynch, John D.
302 Gutenberg downloadsen2010Difficulty 74 (Expert)Records of Harvest Mice, Reithrodontomys, from Central America, with Description of a New Subspecies from Nicaragua
Anderson, Sydney & Jones, J. Knox
302 Gutenberg downloadsen2010Difficulty 55 (Graduate)Some Common Birds Useful to the Farmer (1915 edition)
Beal, F. E. L. (Foster Ellenborough Lascelles)
302 Gutenberg downloadsen2020Difficulty 54 (Graduate)Eugenics as a Factor in the Prevention of Mental Disease
Pollock, Horatio M. (Horatio Milo)
301 Gutenberg downloadsen2011Difficulty 65 (Academic)Rapport sur un voyage botanique en Algérie, de Philippeville à Biskra et dans les Monts Aurès, entrepris en 1853 sous le patronage du Ministère de la guerre
Cosson, E. (Ernest)
301 Gutenberg downloadsfr2024Die Protozoen als Krankheitserreger des Menschen und der Hausthiere Für Ärzte, Thierärzte und Zoologen
Schneidemühl, Georg
300 Gutenberg downloadsde2016Some Common Birds in Their Relation to Agriculture
Beal, F. E. L. (Foster Ellenborough Lascelles)
300 Gutenberg downloadsen2020Difficulty 55 (Graduate)The American Apiculturist. Vol. III. No. 6, June 15, 1885 A Journal Devoted to Scientific and Practical Beekeeping
Various
300 Gutenberg downloadsen2018Difficulty 54 (Graduate)Zwischen Pol und Äquator: Tiergeographische Lebensbilder
Floericke, Kurt
300 Gutenberg downloadsde2022The Ohio Naturalist, Vol. II, No. 1, November, 1901
Ohio State University. Biological Club
299 Gutenberg downloadsen2023Difficulty 53 (Graduate)Additional Records and Extensions of Known Ranges of Mammals from Utah
Durrant, Stephen David & Hansen, Richard M. & Lee, M. Raymond
298 Gutenberg downloadsen2010Difficulty 57 (Graduate)Experiments on the Nervous System with Opium and Metalline Substances Made Chiefly with the View of Determining the Nature and Effects of Animal Electricity
Monro, Alexander
298 Gutenberg downloadsen2014Difficulty 66 (Academic)The Tadpoles of Bufo cognatus Say
Smith, Hobart M. (Hobart Muir)
298 Gutenberg downloadsen2010Difficulty 55 (Graduate)Die krankheiterregenden Bakterien Entstehung, Heilung und Bekämpfung der bakteriellen Infektionskrankheiten des Menschen
Löhlein, Max
297 Gutenberg downloadsde2017Humboldt From 'The Gods and Other Lectures'
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297 Gutenberg downloadsen2011Difficulty 62 (Academic)The Protection of Fresh-Water Mussels
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297 Gutenberg downloadsen2013Difficulty 65 (Academic)Le piante utili dell' Eritrea
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296 Gutenberg downloadsit2025Pleistocene Soricidae from San Josecito Cave, Nuevo Leon, Mexico
Findley, James S. (James Smith)
296 Gutenberg downloadsen2010Difficulty 58 (Graduate)The botanist's repository for new and rare plants; vol. 05 [of 10]
Andrews, Henry Cranke, active 1799-1828
296 Gutenberg downloadsen2024Difficulty 55 (Graduate)The heathery; or, A monograph of the genus Erica. vol. 6
Andrews, Henry Cranke, active 1799-1828
296 Gutenberg downloadsen2023Difficulty 58 (Graduate)The Periodical Cicada, "the 17-year Locust"
United States. Department of Agriculture
296 Gutenberg downloadsen2019Difficulty 51 (Graduate)The Pigmy Woodrat, Neotoma goldmani, Its Distribution and Systematic Position
Rainey, Dennis G. & Baker, Rollin H. (Rollin Harold)
296 Gutenberg downloadsen2010Difficulty 61 (Academic)A természettudomány fejlődésének története (1. kötet)
Bölsche, Wilhelm
295 Gutenberg downloadshu2022An account of the manner of inoculating for the small pox in the East Indies With some observations on the practice and mode of treating that disease in those parts
Holwell, J. Z. (John Zephaniah)
295 Gutenberg downloadsen2016Difficulty 88 (Specialist)The Ohio naturalist, Vol. 1, No. 3, January, 1901
Ohio State University. Biological Club
295 Gutenberg downloadsen2023Difficulty 53 (Graduate)Études sur la flore du Sénégal
Vallot, Joseph
295 Gutenberg downloadsfr2024Het Leven der Dieren: Deel 3.9, De Oerdieren
Brehm, Alfred Edmund
294 Gutenberg downloadsnl2021The Fern Bulletin, October 1903 A Quarterly Devoted to Ferns
Various
294 Gutenberg downloadsen2018Difficulty 50 (College)The Mammals of Washtenaw County, Michigan Occasional Papers of the Museum of Zoology, No. 123
Wood, Norman Asa
293 Gutenberg downloadsen2010Difficulty 44 (College)The Virtue and Use of Coffee With Regard to the Plague and Other Infectious Distempers
Bradley, Richard
293 Gutenberg downloadsen2019Difficulty 63 (Academic)Desert and water gardens of the Red Sea : $b Being an account of the natives and the shore formations of the coast
Crossland, Cyril
292 Gutenberg downloadsen2023Difficulty 50 (College)L'intelligence des fleurs
Maeterlinck, Maurice
292 Gutenberg downloadsfr2020The Hand Phrenologically Considered Being a Glimpse at the Relation of the Mind with the Organisation of the Body
Anonymous
292 Gutenberg downloadsen2016Difficulty 70 (Academic)Complete Treatise on the mare and foal at the time of delivery, with illustrations. Also on cows and calves, with stallion and mare, when diseased by Gonorrhea (clap) or Pox, also Diarrhea and Costiveness in Colts.
Mitchell, Conrad
291 Gutenberg downloadsen2016Difficulty 49 (College)Contagious Abortion of Cows
MacNeal, Ward J.
291 Gutenberg downloadsen2011Difficulty 66 (Academic)Epidemics Examined and Explained: or, Living Germs Proved by Analogy to be a Source of Disease
Grove, John
291 Gutenberg downloadsen2010Difficulty 65 (Academic)A New Species of Frog (Genus Tomodactylus) from Western México
Webb, Robert G. (Robert Gravem)
290 Gutenberg downloadsen2010Difficulty 62 (Academic)An Account of the Sore Throat Attended With Ulcers A Disease Which Hath of Late Years Appeared in This City, and in Several Parts of the Nation
Fothergill, John
290 Gutenberg downloadsen2017Difficulty 67 (Academic)Aus dem Leben der Insekten
Buckley, Arabella B. (Arabella Burton)
290 Gutenberg downloadsde2022House Flies
Howard, L. O. (Leland Ossian)
290 Gutenberg downloadsen2019Difficulty 56 (Graduate)Physiology and histology of the Cubomedusæ including Dr. F.S. Conant's notes on the physiology
Berger, E. W. (Edward William)
290 Gutenberg downloadsen2017Difficulty 62 (Academic)Dairy Disagreeables Busy the Bacteriologists
Hall, Frank H. (Frank Henry) & Harding, Harry Alexis & Rogers, L. A. (Lore Alford) & Smith, George A.
289 Gutenberg downloadsen2022Difficulty 56 (Graduate)The Methods and Scope of Genetics An inaugural lecture delivered 23 October 1908
Bateson, William
289 Gutenberg downloadsen2016Difficulty 60 (Graduate)Catalogue of the dipterous insects collected at Singapore and Malacca
Wallace, Alfred Russel
287 Gutenberg downloadsen2023Difficulty 56 (Graduate)Notes on the Mammals of Gogebic and Ontonagon Counties, Michigan, 1920 Occasional Papers of the Museum of Zoology, Number 109
Dice, Lee R. (Lee Raymond) & Sherman, Harley Bakwel
287 Gutenberg downloadsen2011Difficulty 54 (Graduate)A study of mushrooms and mushroom spawn
Jacob, Edward Henry
286 Gutenberg downloadsen2023Difficulty 50 (College)A study of some factors influencing fertility and sterility in the bull
Gilman, Herbert Lester
286 Gutenberg downloadsen2024Difficulty 67 (Academic)Notes on Diseases of Cattle: Cause, Symptoms and Treatment
Korinek, Charles James
286 Gutenberg downloadsen2019Difficulty 55 (Graduate)The O. S. U. Naturalist, Vol. 1, No. 2, December, 1900
Ohio State University. Biological Club
285 Gutenberg downloadsen2023Difficulty 52 (Graduate)Thoughts on General and Partial Inoculations Containing a translation of two treatises written when the author was at Petersburg, and published there, by Command of her Imperial Majesty, in the Russian Language
Dimsdale, Thomas
285 Gutenberg downloadsen2015Difficulty 67 (Academic)The Florist and Horticultural Journal, Vol. II. No. 7, July, 1853 A Monthly Magazine of Horticulture, Agriculture, Botany, Agricultural Chemistry, Entomology, &c.
Various
284 Gutenberg downloadsen2018Difficulty 55 (Graduate)Bees from British Guiana Bulletin of the AMNH, Vol. XXXVIII, Art. XX, pp. 685-690
Cockerell, Theodore D. A. (Theodore Dru Alison)
283 Gutenberg downloadsen2010Difficulty 55 (Graduate)Florulae Insularum Australium Prodromus
Forster, Georg
283 Gutenberg downloadsla2011Het paard : $b in zijne natuurlijke ontwikkeling
Bölsche, Wilhelm
283 Gutenberg downloadsnl2025La espressione dei sentimenti dei nostri volatili domestici
Pascal, Teodoro
283 Gutenberg downloadsit2017Mammals Collected by Dr. W. L. Abbott on the Natuna Islands Proceedings of the Washington Academy of Sciences, Vol. III, pp. 111-138
Miller, Gerrit S. (Gerrit Smith)
283 Gutenberg downloadsen2014Difficulty 54 (Graduate)Pecan Diseases and Pests and Their Control
Rosburg, David W. & King, D. R.
283 Gutenberg downloadsen2021Difficulty 64 (Academic)The Bedbug [1916]
Marlatt, C. L.
283 Gutenberg downloadsen2020Difficulty 61 (Academic)A New Bat (Genus Myotis) From Mexico
Dalquest, Walter Woelber & Hall, E. Raymond (Eugene Raymond)
282 Gutenberg downloadsen2010Difficulty 57 (Graduate)The Systematic Status of Eumeces pluvialis Cope
Smith, Hobart M. (Hobart Muir)
282 Gutenberg downloadsen2011Difficulty 60 (Graduate)The bedbug : $b Its relation to public health, its habits and life history, and methods of control
United States. Public Health Service
280 Gutenberg downloadsen2023Difficulty 60 (Graduate)A New Species of Pocket Gopher (Genus Pappogeomys) From Jalisco, México
Russell, Robert J.
278 Gutenberg downloadsen2010Difficulty 60 (Graduate)Sweet-Clover Seed
Coe, H. S. & Martin, John N. (John Nathan)
278 Gutenberg downloadsen2020Difficulty 60 (Graduate)The heathery; or, A monograph of the genus Erica. vol. 2
Andrews, Henry Cranke, active 1799-1828
278 Gutenberg downloadsen2023Difficulty 54 (Graduate)Wintering Bees in Cellars
Phillips, Everett Franklin & Demuth, Geo. S. (George S.)
278 Gutenberg downloadsen2019Difficulty 52 (Graduate)Coloured engravings of heaths; vol. 1
Andrews, Henry Cranke, active 1799-1828
277 Gutenberg downloadsen2023Difficulty 60 (Graduate)Darwinism. The Noachian Flood A lecture delivered before the Torquay Natural History Society, Jan. 31st, 1870
Stebbing, Thomas Roscoe Rede
277 Gutenberg downloadsen2021Difficulty 68 (Academic)Flytraps and Their Operation [1921]
Bishopp, F. C. (Fred Corry)
276 Gutenberg downloadsen2020Difficulty 48 (College)Irritability : $b a physiological analysis of the general effect of stimuli in living substance
Verworn, Max
275 Gutenberg downloadsen2021Difficulty 65 (Academic)Nitrogen Bacteria and Legumes With special reference to red clover, cowpeas, soy beans, alfalfa, and sweet clover, on Illinois soils
Hopkins, Cyril G. (Cyril George)
274 Gutenberg downloadsen2018Difficulty 58 (Graduate)The little book of British quadrupeds
May, W.
274 Gutenberg downloadsen2024Difficulty 44 (College)Hints on the History and Management of the Honey Bee Being the Substance of Two Lectures Read Before the Members of the Hereford Literary, Philosophical, and Antiquarian Institution, in the Winter of 1850-51
Bevan, Edward
273 Gutenberg downloadsen2022Difficulty 64 (Academic)Descriptions of Three New Birds from the Belgian Congo Bulletin of the AMNH , Vol. XXXIV, Art. XVI, pp. 509-513, Oct. 20th, 1915
Chapin, James Paul
272 Gutenberg downloadsen2010Difficulty 49 (College)The Kansas University Science Bulletin (Vol. I, No. 1)
Various
272 Gutenberg downloadsen2017Difficulty 50 (College)A New Bat (Genus Pipistrellus) from Northeastern Mexico
Baker, Rollin H. (Rollin Harold)
271 Gutenberg downloadsen2010Difficulty 56 (Graduate)Memoria sobre a cultura da Urumbeba e sobre criação da Cochonilha
Thiéry de Menonville, Nicolas-Joseph & Berthollet, Claude-Louis & Velloso, José Mariano da Conceição
271 Gutenberg downloadspt2012Straußenpolitik : $b Neue Tierfabeln
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271 Gutenberg downloadsde2025Taxonomic Status of Some Mice of The Peromyscus boylii Group in Eastern Mexico, With Description of a New Subspecies
Alvarez, Ticul
271 Gutenberg downloadsen2010Difficulty 52 (Graduate)A Defence of the Inquiry into Mesmerism & Phrenology chiefly in relation to recent events in Lynn
Armes, William
270 Gutenberg downloadsen2017Difficulty 66 (Academic)Sphinx Vespiformis: An Essay
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