GILMORE: the fossil turtles of the UINTA FORMATION 



113 



but broadly, rounded, resembling in its general contour B. sima Hay. The shell 

 is flat transversely in the region of the vertebral scutes, but from one border to the 

 other it is broadly convex. One of the distinctive features of this species is the 

 decided transverse inflation or swelling of the mid-costal region, which gives the 

 shell the appearance of being puffed out on the sides. This swelling lies largely 

 within the areas of the second costal scutes, and it is to this feature that the specific 

 name refers. 



Over the posterior legs the margins of the shell begin to flare outward and 

 slightly upward, and at this point the border is heavy and rounded but becomes 

 thinner posteriorly. In front of the axillary notches the border has a thickness of 

 31 mm., but rapidly thins toward the center, where it measures only 8 mm., the 

 edge being obtusely rounded. The bones of the carapace are so thoroughly coos- 

 sified that but few of the sutures can now be made out. The sulci, however, can 

 in most instances be clearly traced. 



Fig. 2. Carapace of Baena inflata. C. M. No. 3406, Tyije, 

 four; V.S. 1, V.S. 4, vertebral scutes one and four. One-fourth natural size 



C.S. 1, C.S. 4, 



costal scutes one and 



The vertebrals as in nearly all Eocene Baenidai are longer than wide. The 

 sides of the vertebrals, excepting the first, which is hexagonal with a very narrow 

 anterior end, are bracket-shaped. It wiU be observed, that, as in Baena emilm, 

 the third vertebral is the longest of the series. Along the center of vertebrals two, 



