114 FOSSIL TURTLES OF NORTH AMERICA. 



Taphrosphys strenuus Cope. 



Figs. 107- 1 1 1 . 



Taphrosphys princeps, Cope, Cook's Geol. New Jersey, 1868 (1869), p. 735 (name only). 



Taphrosphys strenuus, Cope, Ext. Batracli., Reptilia, Aves N. A., 1870, pp. 157, 166-B; Vert. Cret. 

 Form. West, 1875, p. 264; Kerr's Report Geol. Surv. N. C, 1875, Append. B, p. 34; Amer. Nat- 

 uralist, xii, 1878, p. 128. Hay, Bibliog. and Cat. Foss. Vert. N. A., 1902, p. 439. 



Prochonias strenuus, Cope, Amer. Naturalist, III, 1869, pp. 89, 90; Fxt. Batrach., etc., pp. 159, 167. 



Prochonias princeps, Cope, Amer. Naturalist, III, 1869, p. 89; Ext. Batrach., etc., pp. 160, 167, line 44. 



Altho the present species had been previously mentioned, the earliest description of it is 

 found in Cope's monograph on the Extinct Batrachia, Reptilia, and Aves of North America, 

 page 166-B, issued in April, 1870. Here Cope states that he had in his possession 3 specimens. 

 Only one of these, the second mentioned by him, has been found in his collection in the 

 American Museum of Natural History. This has the number 1 126. It appears that the first 

 specimen mentioned by him had been intended as the type of the species, while the one now 

 numbered 1 126 had been intended as the type of his species princeps. Before the description 

 of the latter was printed it appears that he concluded to abandon it. Cope's description of 

 T. strenuus bears evidences of imperfect revision. The second specimen, number 1 1 26, is 

 labeled by Cope as having been obtained from the West Jersey Marl Company's pits at Barnes- 

 boro, Gloucester County, New Jersey. The level is the Upper Cretaceous. The remains 

 are much broken, consisting of about 75 pieces; and so man}' parts are missing that it is 

 impossible to determine the exact position of many of those which remain. Of the neurals 

 none is preserved. A few fragments of the costals remain. One, probably the fragment 



FlG. 107. Taphrosphys strenuus. Anterior lobe ot plastron. Xj. 

 Known portions shown bv stippled areas. 



whose width and thickness are given by Cope, is 91 mm. long, 57 mm. wide, and 10 mm. thick. 

 The rib scarcely shows on the inferior surface. The upper surface presents a network ot 

 shallow grooves at one end, but at the other the grooves inosculate but little and run nearly 

 parallel with the sutural borders. Cope states that the peripherals are rough from the reticu- 

 late sculpture. A fragment of what is believed to be an anterior peripheral shows a close 

 network of grooves. The greatest thickness of this bone is 21 mm. Its free border is obtuse. 



Large portions ot the plastron are preserved. The bones are thick and heavy. Pieces 

 which belong at the crossings of the sutures measure in thickness about 18 mm., increasing in 

 places to 20 mm. As in other species of the genus, the transverse sutural faces are oblique to 

 the upper and lower surfaces of the plastron, so that the hyoplastron overlapt somewhat the 

 hypoplastron; and the latter, the xiphiplastron. On the inferior surface the network ot 

 grooves is coarse. On one fragment is seen a narrow and shallow sulcus. 



The anterior lobe of the plastron was broad and short (fig. 107). The right epiplastron is 

 present and shows the whole of its free border, but some of the entoplastral border is broken 

 away. To this is attacht a part of the free border of the hyoplastron. The width of the lobe 

 at the hyoepiplastral suture was close to 300 mm. The front of the lobe was concave for a 

 considerable distance on each side the midline. The fragment of hyoplastron is 18 mm. thick, 

 but it thins to the subacute free border. On the epiplastron the free border becomes obtuse, 

 the thickened part of the bone coming nearer the edge than on the hypoplastron. \t the 

 epiplastral symphysis the bone rather suddenly thickens to 22 mm. 



