TESTUDINID^E. 



463 



wide. On the lower surface of the bone is seen the femoro-anal sulcus, running parallel with 

 the hinder border of the bone. The area occupied by the anal scute is rough and it occupies 

 a slightly different level from the rest of the bone. 



As stated by Cope, this species may belong to the genus Gopherus (Xerobates), but this 

 can not be determined before the skull has been found. 



Testudo hexagonata Cope. 

 Figs. 625, 626. 



Testudo hexagonata, COPE, Geol. Surv. Texas, iv, 1903, reprint p. 77, plate xxii, fig. 2. HAY, Bibliog. 

 and Cat. Foss. Vert. N. A., 1902, p. 451. GIDLEY, Bull. Amer. Mus. Nat. Hist., xix, 1903^.623. 



The present species is based on a specimen now in the University of Texas, at Austin, 

 Texas, where the writer has been permitted to study it. The specimen was found by Prof. W. F. 

 Cummins, of the Texas Geological Survey, in the Equus beds, on Rock Creek, a stream 

 emptying into Tule Canyon, in Briscoe County, Texas. 



The carapace of this shell is considerably crusht and fractured, and somewhat weathered. 

 Various parts of the free border are missing. It is therefore difficult to secure the details of the 

 structure, and this portion of the shell was not described by Cope. A figure is here presented 

 (fig. 626) which gives as well as could be determined the structure of the carapace. 



FIGS. 625 AND 626. Testudo hexagonata. Shell of type. 

 625. Half of lower surface of shell. From Cope's figure. Xj. 626. Carapace, partly restored. Xj. 



The length of the carapace is 380 mm.; the width, 330 mm. The peripherals in front and 

 behind the bridge appear not to have been flared upward to any considerable extent. Poste- 

 riorly the carapace appears to have been steep. Not much can be determined regarding the 

 arrangement of the neurals, on account of distortion. The first had a width of about 45 mm. 

 The second is octagonal, with a length of 45 mm. and a width of nearly 70 mm. The third 

 was 4-sided. The second costal bone is narrowed proximally and greatly widened distally, 

 being here about 65 mm. wide. The fourth and sixth costals have a similar form. The third 

 and fifth are widened proximally and narrowed at the distal ends. 



