4.38 FOSSIL TURTLES OF NORTH AMERICA. 



In some of his earlier references to this species Leidy was in doubt regarding its distinctness 

 from Stylemys nebrascensis, but in his latest description he pointed out one character which 

 definitely separates it from the White River species. This is found in the lip, which projects 

 well beyond the general contour of the plastron and has a deep excavation beneath its backward 

 extension on the upper surface of the lobe. 



The plastral lip (figs. 575, 576) is 36 mm. wide, measured from where one gulo-humeral 

 sulcus crosses the free border to the crossing of the other. From a line on the upper side join- 

 ing these points the rounded, slightly notcht lip extends forward 13 mm. and backward 9 mm. 

 Its hinder border overhangs the excavation. The gulo-humeral sulci on this upper surface are 

 18 mm. long, that is, about one-third of the width of the base of the lip. The present thickness 

 of the lip is 18 mm. It appears to have been somewhat convex from side to side above. 



From the original of Leidv's fig. 6, plate iii, we learn that the fourth vertebral scute was 

 155 mm. long and 148 mm. wide, and that it occupied a portion of the eighth neural. 



The pygal (fig. 577) widens from the free to the superior border. Above, it is somewhat 

 excavated for the reception of the suprapygal. As shown by fig. 578, which represents the 

 perpendicular section thru the pygal and the suprapygal, the pygal was slightly flared outward. 

 The free border is obtuse. The greatest thickness is 13 mm. 



The part of the carapace figured by Leidy (No. 93, U. S. N. M.) must have belonged to an 

 individual about 610 mm. long. The part included the sixth, seventh, and eighth neurals, 

 parts of the corresponding costal plates, and the upper end of the bifurcated suprapygal. The 

 fourth vertebral scute had a length of 155 mm. The upper ends of the costals are 15 mm. 

 thick. The limb bones figured by Leidy offer no novel characters. 



This species appears to be distinguisht from both T. vaga and the younger specimens of 

 T. osborniana by the more prominent plastral lip and the shortness of the gulo-humeral sulcus 

 on the upper side of each epiplastron. The pygal appears to differ from that of T. osborniana 

 in being obtuse on the free edge. It appears likewise to belong to a more recent formation than 

 either of the species just named. From T. farri of the Deep River formation it differs in the 

 more projecting epiplasti al lip and more elongated entoplastron. 



Testudo orthopygia (Cope). 

 Plate 19, figs. 6, 7; plates 72-75; 78-80, fig. 1; test-figs. 579-606. 



Xerobates orthopygius, Cope, Bull. U. S. Geol. and Geog. Surv. Terrs., IV, 1878, p. 393. 



Testudo orthopygia, Hay, Amer. Geologist, xxiv, 1899, p. 349; Bibliog. and Cat. Foss. Vert. N. A., 



1902, p. 45 1 - 

 Xerobates cydopygius, Cope, Bull. U. S. Geol. and Geog. Surv. Terrs., IV, 1878, 394. 

 Testudo cyclopygia, Hay, Amer. Geologist, xxiv, 1899, p. 349; Bibliog. and Cat. Foss. Vert. N. A., 1902, 



p. 451. 

 Caryoderma snovianum, Cope, Amer. Naturalist, XX, 1886, p. 1044; Amer. Naturalist, xxni, 1889, 



p. 662, plate xxxii, figs, r 1 7. 

 Testudo undata?, Williston, Science (2), vm, 1898, p. 132. 

 Testudo snoviana, Hay, Bibliog. and Cat. Foss. Vert. N. A., 1902, p. 451. 



In the year 1877 a party consisting of Messrs. C. H. Sternberg, R. S. Hill, and W. J. Brous 

 collected from the Loup Fork beds of Decatur County, Kansas, a considerable number ot 

 specimens of turtles belonging to the genus Testudo. Out of these materials Professor Cope 

 described 2 species, giving them the names referred to him in the synonymy above. These 

 specimens are now in the American Museum of Natural History and have been studied by the 

 present writer, with the result that they are all' assigned to one species, which must bear the 

 name orthopygia. According to Cope's description, there existed between his two species a 

 great difference, one having the hinder border of the carapace broadly rounded, the other 

 having it nearly straight and with rounded angles behind the inguinal notches. This striking 

 difference, however, disappeared when it was discovered that Cope had mistaken the anterior 

 border of the carapace of the type of his orthopygia for the posterior. This being the case, it 

 would be more appropriate to call the species cyclopygia, but the other name having preceded 

 the latter in the description, we must, according to rules adopted, retain the name orthopygia. 



The type of the species T. orthopygia bears the museum's number 3929. It consists of the 

 skull and lower jaw; the plastron quite complete; nearly the whole of the anterior free border 



