LIFE AND WORKS OF COPE. IX 



tology and his third contribution to the history of the Ce- 

 tacea. Henceforward his papers become far too numerous 

 to consider together and we must endeavor to follow merely 

 the main outlines of his life-work. 



This was a bright era in the history of the Philadelphia 

 Academy ; Leidy, Gill, and Harrison Allen being frequent 

 •contributors. In 1868 Cope gave his first complete synop- 

 sis of the extinct Amphibia of the world. Between 1868 

 and 1870 he made his first six contributions upon the Plesio- 

 saurs and Mosasaurs of the Cretaceous of Kansas, and in 

 1871 began his first western explorations in these beds. 

 This led to his appointment as Vertebrate Paleontologist 

 of the U. S. Geological Survey, under Dr. Hayden, and to 

 further explorations in Wyoming (1872) and Colorado 

 (1873), which resulted in the discovery of many new types 

 of fishes, mosasaurs, chelonians, dinosaurs and other rep- 

 tiles, notably, Pmiheus, Platecarpus, Clidastes, Compsemys 

 (type of the Amphichelydia, Lydekker), Protostega, and 

 Agaihaumus. These were described chiefly in the Annual 

 Reports of the U. S. Geological Survey and in the Proceedings 

 and Transactions of the American Philosophical Society, and 

 then culminated in his first large volume " The Vertebrata 

 of the Cretaceous Formations of the West," No. II, of the 

 Hayden quartos, which was published in 1875. 



He spent his summers in the Bad Lands, exploring the 

 Bridger and Washakie, Wasatch, New Mexican, and Judith 

 River (1887) formations. The latter exposures he visited 

 in 1874, in connection with the Wheeler Survey (Geological 

 ■ Surveys West of the 100th Meridian) securing a collection 

 which is now preserved in the National Museum, and pub- 

 lishing a most vivid description of the geology of this in- 

 teresting region. His movements in the field are described 

 by one who was with him as so rapid and full of energy, 

 so regardless of food and rest, that he wore out the other 

 members of his parties and did not allow time for thorough 



