G. R. Wieland — Upper Cretaceous Turtles. 191 



the plastron, marginals 2 and 8 being deeply pitted for the 

 extreme ends of the hyo- and hypoplastron, respectively, as 

 explained in the description of 0. Gibbi and Propleura. In 



t 



Figure 5. — Osteopygis sp. (Yale specimen 908). x £. Eight eighth pleural 

 with the ninth neural and a portion of the antero-pygal (P) attached. Horn- 

 shield borders of fourth and fifth vertebralia and fourth costal horn-shields 

 distinct and shown in triple line. (Thickness of neural is - 7 cm.) 



Figure 6.— Propleura sp. (Yale specimen 559). x £. Right and left seventh 

 and eighth pleuralia and seventh neural with borders of the fourth and fifth 

 vertebral and the fourth costal horn- shields distinct and shown in triple line. 

 Stippled portions only preserved. 7-9, neuralia ; VII, VIII, pleuralia ; P, 

 antero-pygal ; f,f,f, the three posterior pleuro-marginal fontanelles. (Thick- 

 ness of pleuralia at sutural edge 3- '5 cm.) Barnsboro, New Jersey. 



the living Cheloninse, the marginal pits for the plastral digita- 

 tions are indistinct. Hence, Lytoloma is also intermediate in 

 this respect. 



