LEIDY, li'df, Jos= (1823-91). A distin guished American naturalist, born in Philadel phia, l'a. lle obtained his degree in medicine at the University of Pennsylvania in 1844, executed the dissections and drawings for the work on Termstrial and Air-Breuthing Mollusks of the United Mates (Boston, 1845). by Amos Ilinney, was appointed eliairman of the Board of Curators of the Academy of Natural Sciences in 1846. and became demonstrator of anatomy in the Uni versity of Pennsylvania. ln 1853 he was ap pointed full profess(o- of anatomy in the School of the university, and in 1882 professor of biology in the Faculty of Philosophy. Ile was also the first director of the biological depart ment of the university, organized in 1885; and for a time occupied the chair of natural history in Swarthmore College. In 1881 he was elected president of the Aeademy of Natural Sciences at Philadelphia, and in 1885 president of the Wagner Free Institute of Science in that city. He reeeived the Walker grand honorary prize of the Boston Society of Natural History in 1880, and, for distinguished contributions to the sei epee of paleontology. the Sir Charles Lye]] medal of the Royal Geological Society of London in 1884, and the Cuvier medal of the Institut de France in 1888. His contributions to the natural sciences included comparative anatomy, botany, mineralogy, geology, and microscopic zo6logy, helminthology, and more especially pa leontology. His researches in connection with the fossil horse and camel. published in the P•o ceedings of the Academy of Natural Sciences and of time Smithsonian Institution from 1847 to 1891, were of acknowledged service to Darwin and Sir Charles Lyell. lie also discovered (1846) the
hog to be the host by which the parasite Trichina spiralis is introduced into the human system. His writings include numerous papers contributed to the Transortions of the American Philosophical Society. the publications of the Wagner Free Institute of Seienee. Smithsonian publications under the auspices of the United States Geo logical Surveys, and the Journal and Pro ceedings of time Academy of Natural Seiences in all. upward of 1000; A Flora and Fauna Liring Animals (1851) ; Description of the Remains of Extinct Maimmalia and Che Ionia from Nebraska Territory (1852) ; Cre taceous Reptiles of the United Rtates (1865) ; The Extinct Mammalia Fauna of Dakota and Nebraska (1869) ; Contributions to the Extinct lerlebrate Fauna of the Western Territories (1873) ; The Fresh-Water Rhizopods of North America (1879) ; Treatise on human Anatomy (1861-89). Dr. Leidy was an honorary member of more than sixty-live scientific societies of the United States and other countries. Consult the article by Frazer in vol. ix. of the A merican Geologist (Minneapolis. 1892), also reprinted as a monograph ; the memoirs by H. C. Chapman. in the Proceedings of the Academy of Natural Sci ences; by Rusehenberger,in those of the American Philosophical Society (1891) ; by Geikie, in those of the Geological Society of London (1892) ; and in the publications of the Royal Microscopical Society, London (1891), and the American Jour nal of .trts and Sciences (1891).
LEIF (1ff) ER'ICSON. See ERICSON, LEIF.