An Introduction to the Study of Zoology (Barnes & Noble Digital Library) Illustrated By the Crayfish – (PDF/EPUB Version)

This classic introduction to zoology isolates a single creature, the crayfish, in order to instruct the reader in the general principles of morphology, physiology, and the behavior of the animal. Huxley hoped that this monograph would show how his description of one animal could provide the “foundation for the whole of biological science.”