Asa Gray, an American botanist, born in Paris, Oneida co., N. Y., Nov. 18, 1810. He graduated at the Fairfield medical college in 1831, but abandoned the practice of medicine, and applied himself to the study of botany. In 1834 he was appointed botanist to the United States exploring expedition; but as some time elapsed before it was ready to sail, he resigned that situation. In 1842 he was elected Fisher professor of natural history in Harvard college. In his numerous writings he has shown equal ability in communicating elementary knowledge and in elucidating recondite theory. His elementary works, "Elements of Botany," published in 1836, and especially his later series, "How Plants Grow," "How Plants Behave," "Lessons in Botany," and "Structural and Systematic Botany " (1858), are unsurpassed in the language for precision, simplicity, perspicuity, and comprehensiveness. His labors are recorded in numerous papers contributed to the principal scientific journals and academical memoirs of the day, and in several special works, He came forward at a time when the old artificial systems of botany were giving way before the natural system. Dr. Gray, with Dr. John Torrey, was among the first who arranged the heterogeneous assemblage of species upon the natural basis of affinity.

While actively engaged in describing the new forms which were pouring in upon them from numerous explorations in our hitherto almost unknown territory, they were elaborating the accumulated knowledge of their predecessors which remained in a crude form. In 1838 Dr. Gray commenced, in conjunction with Dr. Torrey, the publication of a "Flora of North America," intended to give a thorough and comprehensive history of the botany of the country upon the basis of the then little known natural system. This was continued as far as the end of the order compositoe; but as the explorations of several collectors were accumulating masses of new material from our western borders, the "Flora" was suspended until this wealth of matter could be aggregated under one head. The government expeditions to the Pacific coast also returned laden with botanical treasures, which were described by Dr. Gray and Dr. Torrey in the government reports. In 1848 Dr. Gray began his "Genera of the Plants of the United States, illustrated by Isaac Sprague," and in the same year the " Manual of the Botany of the Northern United States," several editions of which, enlarged and amended, have since appeared.

In 1854 appeared the first volume of the "Botany of the United States Pacific Exploring Expedition under Capt. Wilkes," a work in which the author has shown himself able to treat of the botany of remote regions with the same critical power that he has applied to the North American flora. In 1861 he published "A Free Examination of Darwin's Treatise on the Origin of Species, and of its American Reviewers." He is an associate editor of the " American Journal of Science and Arts." In 1873 he retired from active service in teaching, to devote himself to the charge of the herbarium of Harvard college, and to scientific work. In 1874 he was appointed a regent of the Smithsonian institution in place of Prof. Agassiz.