Born May 13, 1854, in Avignon; died Oct. 7, 1920, in Sceaux, department of Hauts-de-Seine. French zoologist. Member of the Paris Academy of Sciences (1901).
Delage’s studies on invertebrate morphology (development of parasitic crustaceans [sacculinas], turbellarians, sponges, and so forth) are generalized in the multivolume work Treatise of Pure Zoology (1896-1901), which he wrote with E. Hérouard. Delage devoted special attention to the study of fertilization and parthenogenesis. He succeeded in growing parthenogenetic sea urchins from the larval stage to the adult stage. He founded the journal L’Année biologique.