MEMOIRS 
OF THE 
CAIRN IDEA AiUhS a Ue 
VOL. LE NOP. 
THE OSTEOLOGY OF PROTOSTEGA. 
By G. R. WIELAND. 
The first mention of ancient gigantic marine turtles from America was made by 
Cope in 1871 ina letter to Professor J. P. Lesley containing an account of a journey 
in the valley of the Smoky Hill River in Western Kansas. This letter, as subse- 
quently published in the Proceedings of the American Philosophical Society,’ 
includes a preliminary notice of the huge Niobrara Cretaceous turtle, Protostega 
gigas. ‘The type specimen was collected by Cope himself on a bluff near Butte 
Creek in the vicinity of Fort Wallace. It was secured in a more or less fragmentary 
condition after the manner of the vertebrate collecting of the earlier days of western 
exploration, for, in the more extended description given in the Cretaceous Vertebrata 
of the West, Cope says this fossil is made up of more than eight hundred separate 
fragments. 
The various parts of Protostega gigas (type), although mostly in situ, were con- 
siderably removed from their natural position. The original specimen is now in the 
collection of the American Museum of Natural History. It includes much crushed 
eranial elements with portions of the lower jaw, ten nearly free ribs, several verte- 
bree, various plastral elements, the shoulder girdle, a humerus, radius, and ulna, and 
several metacarpals and marginals, as well as parts of uncertain position. Owing, 
however, to the manner in which the ribs lay athwart the rather imperfect plastral 
plates, the latter were supposed to be dorsal, and to represent a very primitive con- 
dition of carapacial development with large fenestree. The radius and ulna were 
1 Vol. XIL., p. 175. 
279 
