Books in Biology (sorted by popularity)
- Darwin and Modern Science A. C. Seward 136 downloads
- The Human Side of Animals Royal Dixon 130 downloads
- Evolution in Modern Thought 129 downloads
- The Life-Story of Insects George H. Carpenter 119 downloads
- Lamarck, the Founder of Evolution: His Life and Work A. S. Packard 115 downloads
- The Story of the Living Machine H. W. Conn 113 downloads
- Life History of the Kangaroo Rat Charles Taylor Vorhies and Walter P. Taylor 104 downloads
- My Studio Neighbors W. Hamilton Gibson 98 downloads
- De l'origine des espèces (French) Charles Darwin 97 downloads
- Ducks at a Distance: A Waterfowl Identification Guide Bob Hines 96 downloads
- Species and Varieties, Their Origin by Mutation Hugo de Vries 95 downloads
- Anecdotes of the Habits and Instinct of Animals Mrs. R. Lee 95 downloads
- Text Book of Biology, Part 1: Vertebrata H. G. Wells 93 downloads
- "Wee Tim'rous Beasties": Studies of Animal life and Character Douglas English 91 downloads
- Souvenirs entomologiques - Livre I (French) Jean-Henri Fabre 90 downloads
- Nouveaux souvenirs entomologiques - Livre II (French) Jean-Henri Fabre 83 downloads
- Nature Near London Richard Jefferies 81 downloads
- Darwin, and After Darwin, Volumes 1 and 3 George John Romanes 80 downloads
- Facts and Arguments for Darwin Fritz Müller 79 downloads
- The Minds and Manners of Wild Animals: A Book of Personal Observations William T. Hornaday 76 downloads
- The Origin of Species Thomas Henry Huxley 76 downloads
- Evolution, Old & New Samuel Butler 73 downloads
- Darwiniana; Essays and Reviews Pertaining to Darwinism Asa Gray 72 downloads
- Parasiten der Honigbiene (German) Eduard Philibert Assmuss 72 downloads
- Ohio Biological Survey, Bull. 10, Vol. 11, No. 6 Bruce Fink and Leafy Jane Corrington Hilker 71 downloads