257 



PltOTOSTEOA TUBEEOSA. Cope. 



Proceedings of the American Philosophical Society, 1872, 433 (where riakcarpus is written 

 (?aj;sit calami) ; and Haydcn's Annual Report of the United States Geological Survey, 

 1872, 330, 334. — Atlantochelys tuherosus, Lcidy, Report to the United States Geological 

 Survey of the Territories, 4to, vol. 1, 1873, p. 342. 



Cretaceous of Mississippi. 

 Protostega neptunia, Cope. 



Proceedings of the American Philosophical Society, 1872, p. WA.—Attantoehelys movtonii, 

 Leidy, Report of the United States Geological Survey of the Territories, I, 1873, p. 

 342; Mosasaurus mitclrilii, Leidy (pars), Cretaceous Reptiles of the United States, 

 1SG5, p. 43, 116, Plate VIII, figs. 3-4. 



Grecnsand, No. f, of New Jersey. 



LYTOLOMA, Cope. 



Extinct Batraehia and Reptilia of North America, 1870, p. 144. 



Lytoloma jeanesii, Cope. 



L. c, p. 145. 



Greensand of No. 5, New Jersey. 



Lytoloma angusta, Cope. 



i.e., p. 145; Chelonc sojiila (part), Leidy, Cretaceous Reptiles of the United States, p. 105, 

 Plate XLX, fig. 2. 



Greensand of No. 5, New Jersey. 



OSTEOPYGIS, Cope. 



Proceedings of the Academy of Philadelphia, 1808, p. 147 ; Extinct Batraehia and Reptilia of 

 North America, 1870, p. 132. 



In this genus, the alveolar surfaces are horizontal, very wide, and entirely 

 flat. The alveolar edge is not generally reflexed, even at the broadly-rounded 

 apex, but is acute. As already described, there arc eleven marginal bones, 

 which, with the pygal, make twenty-three in all. The first and last are 

 without corresponding costal bone, so that the number of the latter is nine. 

 I formerly suspected that the eleventh marginal of the O.sopitus is connected 

 with a special costal, the entire number in this species being thus ten ; but 

 subsequent investigation does not establish the view, though it is not yet dis- 

 proves For the present, therefore, I place this species in Osteopygis. I now 

 add another species to the genus, making the entire number four; and the 

 following table points out the distinctive characters: 

 33 c 



