140 THE WABATOU AM-) BHIDGEII FAUNuE. 



HADRIANUS Cope. 



Proceedings of the Aniericau Philosopbical Society, 1872, i>. 468. 



This genus resembles Testudo in form, but has two anal scuta, as in 

 most Emydiddc. The claws are short and stout ; one ungual phalange is a 

 long oval viewed from above, and is oval in section, with obtuse edges. 

 The articular surface is subinferior. A cervical vertebra is of moderate 

 length and has a very prominent anterior zygapophysis. The centrum 

 presents two distinct convex articular surfaces anteriorly, and one trans- 

 verse one behind. A sacral is free from the carapace above ; it presents 

 two surbround articular cups posteriorly and outwardly ; the anterior are 

 broken off. These characters are observed in a large specimen of H. corsoni. 



Hadrianus allabiatus Cope. 



Proceedings of the American Philospbical Society, 1872, p. 471. 

 Plate XIII, iigs. 13-15. 



This large land tortoise differs from both the //. quadratus and the H. 

 octonarius in the absence of the projecting lip of the anterior lobe of the 

 plastron, which is thus simply truncate. The mesosternum is not cordate, 

 but has much the shape of that of //. quadratus; that is, rhombic. The 

 scutal sutures are dee])ly impressed. The plastron is strongly concave. 

 Carapace without irregularities of the surface. Length eighteen inches. 



From the bad lands of Cottonwood Creek, Wyoming. 



Hadrianus octonarius Cope. 



Proceedings of the American Philosophical Society, 1872, p. 468. 

 Phito XX. 



The //. octonarius is distinguished from its congeners as follows. It 

 is of elongate form, strongly contracted at the bridges, but expanded and 

 arched above the limbs. The carapace is very convex. The plastron has 

 the posterior lobe emarginate rather tlian bifurcate, as seen in H. corsoni. 

 Each projection represents a right-angled triangle rather than a wedge. 

 The anterior lobe presents an elongate lip, which is expanded and slightly 

 emarginate, at the end. The mesosternal bone is heart-shaped, the posterior 

 emargination being widt; and not very deep. 



