170 



FOSSIL TURTLES OF NORTH AMERICA. 



For description of the shoulder-girdle (fig. 206, from Case) and remarks thereon, see page 

 [66. The structure of the anterior limb has also been described and illustrated. 



No pelvis definitely known to belong to this species has been described. References to 

 femora supposed to belong to this species have already been given, but these may have belonged 

 to other species, as T. procax or T . brai hyrhina. Case (op. cit., p. 378) describes a hind foot 

 which he refers to T . latiremis. This has already been mentioned on page 167. 



\\ agner has described and figured a portion of a skull of a turtle from the Pierre shales 

 of Kansas, which he identifies as T. latiremis. The present writer has not seen this skull. 

 The lower jaw figured bv Wagner certainly does not belong to T. latiremis. 



Toxochelys serrifer Cope. 

 Figs. 207-212.. 



Toxochelys serrifer, Cope, Vert. Cret. Form. West, 1875, p. 299. Hay, Bibliog. and Cat. Foss. Vert. 

 N. A., 1902, p. 442; Bull. Amer. Mus. Nat. Hist, xxi, 1905, p. 178, figs. 1-7. 



The type of this species is No. 1835 of the Cope collection of reptiles and fishes in the 

 American Museum of Natural History, New York. It consists of the greater portion of both 

 maxilla?, the left dentary, the greater portion of the pterygoids, the right quadrate, the frontals 



208. 



FlGS. 207-212. Toxochelys serrifer. 

 Shows cutting-edge and grinding- 



209. 



212 



207. Left dentarv 



surface. 



208. View of inner face of dentary. 

 20*). Symphysis of lower jaw. 



Portions of skull of type. XI. 



210. Cutting-edge and gnnding-surface of upper jaw. 



mx, maxdla; pal, portion of palatine. 



21 1 . Base of skull, hoc, basioccipital; pf, pterygoid. 



212. I'pper aspect of skull, fr, frontals; pa, parie- 



tal; prf, prefrontal. 



and prefrontals, and two peripherals. They were collected somewhere in the Niobrara deposits 

 of Kansas by Professor Merrill, in 1865. 



The dentarv (figs. 207-209) had not yet become co-ossified with its fellow. Its length is. 

 as Cope states, 48 mm.; its width above, 9 mm.; the depth of the inner face, 7 mm. Longi- 

 tudinally the alveolar surface is more strongly concave than in T. latiremis. Near the sym- 

 physis the surface is considerably concave transversely, but posteriorly it is nearly flat. The 

 inner border of this surface is nearly on the same level as the outer. At the symphysis (fig. 209) 

 the alveolar surface extends nearly as far backward as does the lower face of the bone. The 

 inner face of the dentary is occupied by a broad groove. The length of the alveolar surface of 

 the symphysis is 9 mm. 



Slightly more than the posterior half of each maxilla (fig. 210) is present. The alveolar 

 surface is flat, and the cutting-edge retains its height to its hinder end. In T . latiremis the 

 height becomes reduced posteriorly. The pterygoids (fig. 211, pt) present no peculiarity. 

 Where narrowest the portion of the palate formed by the pterygoids is 15 mm. wide. The 

 quadrate does not differ from that of T. latiremis, except that the articular surface for the 



