Rene Joachim Henri Dutrochet, a French physiologist, born at Neon, Poitou, Nov. 14, 1776, died in Paris, Feb. 4, 1817. His family was rich and noble; but its property having been confiscated during the revolution, he studied medicine in Paris, and served in the army as physician in the Spanish campaigns of 1808-'9. The rest of his life he passed chiefly on his estate in Touraine. He published researches upon the formation of the eggs in birds and fowls, the gradual unfolding of the allantois in the incubated egg, the increase of the young as the albumen diminishes, the structure and growth of feathers, the envelopes of the foetus of mammalia and of the human foetus, and the growth of vegetables and insects. His most remarkable achievement was the discovery of endosmosis in 1828, and in that year he published Recherches sur l'en-dosmose et l' exosmose. His principal writings were collected in 1837 under the title of Memoirs pour servir d l'histoire anatomique et physiologique des vegetaux et des animaux; and in 1842 he published Recherches physiques sur la force epiploique.