HALL, James, paleontologist, born in Hingham, Massachusetts, 12 September, 1811. He was graduated at the Rensselaer school (now the Troy polytechnic institute) in 1832, and remained there as assistant professor of chemistry and natural sciences until 1836, when he was made professor of geology. On the organization of the geological survey of New York in 1836, he was appointed assistant geologist of the second district, and in 1837 was made state geologist in charge of the fourth district. He begun his explorations in the western part of the state during that year, and from 1838 till 1841 published annual reports of progress. In 1843 he made his final report on the survey of the fourth geological district, which was published as "Geology of New York," Part IV. (Albany, 1843). Retaining the title of state geologist, he was placed in charge of the paleontological work. His results have been embodied in the "Paleontology of New York" (Albany, 1847-'79), of which five volumes have at present been given to the public. In addition to the foregoing, Professor Hall has prepared a complete revision of the palaeozoic brachiopoda of North America, with fifty plates. This comprehensive study of the palaeozoic fauna of New York, which is to terminate with the base of the coal formation, has demanded researches beyond the limits of the state, and Professor Hall has extended his investigations westward to the Rocky mountains. These explorations have served as the basis of all our knowledge of the geology of the Mississippi basin. The general results of these comparative studies will be found in the introduction to the third volume of the "Paleontology." In 1855 he was offered the charge of the paleontology of the geological survey of Canada, with promise of succeeding Sir William E. Logan as director, but declined the offer. Subsequently he prepared a monograph on the "Graptolites of the Quebec Group" (Montreal, 1865), which was contributed to the Canadian survey. Professor Hall also held the appointments of state geologist of Iowa in 1855, and of Wisconsin in 1857. For the former he prepared the geological and paleontological portions of the two volumes of the "Geological Survey of Iowa" (Albany, 1858-'9), and he wrote the chapters on physical geography, geology, and paleontology for the" Report on the Geological Survey of the State of Wisconsin" (Madison, 1862). The examination and description of the specimens collected for the government frequently have been assigned to him, and he has written the paleontological portions of "Fremont's Exploring Expedition; Appendix A" (Washington, 1845); "Expedition to the Great Salt Lake" (Philadelphia, 1852); "United States and Mexican Boundary Survey" (Washington, 1857); and "United States Geological Exploration of the Fortieth Parallel," vol. iv. (1877). In 1866, on the reorganization of the New York state museum, he was appointed director, which place, in addition to that of state geologist, he still holds. In connection with this office he has made each year, in his annual reports, valuable contributions to science. Professor Hall has devoted much time to crystalline stratified rocks, and was the first to point out the persistence and significance of mineralogical character as a guide to classification. He has also laid the foundation for a rational theory of mountains. He received the degree of A. M. from Union in 1842. and that of LL.D. from Hamilton in 1863, and from McGill in 1884. Professor Hall received the quinquennial grand prize of $1,000 awarded in 1884 by the Boston society of natural history. In 1840 he was one of the founders of the American association of geologists and naturalists, and after its growth into the American association for the advancement of science was elected president in 1856, delivering his retiring address, on "Contributions to the Geological History of the American Continent," at the Montreal meeting in 1857. He was one of the original members of the National academy of sciences. In 1876 he was one of the founders of the International congress of geologists, and was one of the vice presidents at the session held in Paris in 1878, also in Bologna in 1881, and in Berlin in 1885. He was elected one of the fifty foreign members of the geological society of London in 1848, and in 1858 was awarded its Wollaston medal. In 1884 he was elected correspondent of the Academy of sciences in Paris, and he is a member of many other scientific societies at home and abroad. Besides his larger works, most of which have been referred to, he is the author of nearly 250 separate papers, of which a full list, from 1836 till 1882, is given in the "Thirty-sixth Annual Report of the New York Museum of Natural History" (Albany, 1884).