J line 5, 1885.1 



SCIENCE. 



457 



the Albany medical college in 1838, and was 

 afterward transferred to the professorship of 

 obstetrics, his connection with the college con- 

 tinuing until 1852. 



Dr. Emmons's chief claim to remembrance 

 lies in his work as a geologist. A favorite 

 pupil of Professor Amos Eaton, he soon be- 

 came interested 

 in the mineralo- 

 gy and geology 

 of the western 

 part of Massa- 

 chusetts, and 

 the adjacent re- 

 gion of the state 

 of New York. 

 Appointed pro- 

 fessor of natural 

 history at Wil- 

 liams college in 

 1833, he held 

 that position till 

 1859, when he 

 became profes- 

 sor of mineralo- 

 gy and geology, 

 an office which 

 he held until his 

 death in 1863. 



His appoint- 

 ment as geolo- 

 gist of the sec- 

 ond district of 

 the geological 

 survey of New 

 York in Jul}', 

 1836, gave the 



opportunity for the exercise of his power of 

 acute observation in the field, which made his 

 great reputation as a geologist. In 1837 Dr. 

 Emmons first named, described, and classified 

 the celebrated ' Potsdam sandstone.' In 1842 

 he pointed out a great system of stratified rocks 

 under the Potsdam, which he called the ' Ta- 

 conic system.' Two years later Dr. Emmons 

 first described the primordial fauna, preceding 

 the celebrated discoveries of Barrande, who 

 recognized Emmons's right of priority in the 



^sdz****^'^^ 



following very courteous manner : " In compar- 

 ing these dates, it is clear that Dr. Emmons 

 was the first to announce the existence of a 

 fauna anterior to that which had been estab- 

 lished in the ' Silurian system ' as characteriz- 

 ing the 'lower Silurian' division, and which I 

 have named the second fauna. It is, then, 



just to recognize 

 this priorit}', 

 and I think it all 

 the more fitting 

 to state it at 

 this time, that it 

 has not hitherto 

 been claimed." 

 At a later date 

 Emmons pub- 

 lished further 

 details, and de- 

 scribed several 

 other primordial 

 fossils in his 

 ' American ge- 

 ology ' and 

 'Manual of ge- 

 ology ' in 1855 

 and 1859. 



The following 

 familiar names, 

 divisions, and 

 classifications, 

 of the paleozoic 

 rocks of New 

 York, are also 

 due to Emmons: 

 Chazy lime 

 stone, black 

 marble of Isle la Motte, Lorrain shales, Cham- 

 plain group, Ontario group, Helderberg series, 

 and Erie group. 



In 1851 Dr. Emmons was appointed state 

 geologist of North Carolina. His discoveries 

 in the coal-measures of Deep and Dan rivers, 

 of a splendid triassic flora, with old vertebrates, 

 such as fishes, saurians, and finally of the oldest 

 mammal (Dromatherium sylvestre) yet found, 

 not only in America, but in the whole world, 

 are justly counted among the most important 



