Geoffroy Saint-Hilaire, Isidore

Born Dec. 16, 1805, in Paris; died there Nov. 10, 1861. French zoologist. Son of E. Geoffroy Saint-Hilaire. Professor of zoology in the National Museum of Natural History (from 1841) and the University of Paris (from 1850). Member of the Institute of France (1833) and president of the Paris Academy of Sciences (1856-57).

Geoffroy Saint-Hilaire subscribed to his father’s views on the unity and evolution of the animal world. Attacks on his father’s theories led him to soften his views and to advance the theory of variability limited to species. In continuing his father’s research on monstrosities, he published a series of works on hermaphroditism in man. He founded a society for the acclimatization of economically useful animals. His study on the domestication of new animal species attracted the attention of C. Darwin and such progressive Russian scientists as K. F. Rul’e, N. A. Severtsov, and A. P. Bogdanov.