EEPTILIA OF KIRTLAND FOEMATION GILMORE 



171 



The few anterior neurals that can be traced out have the same 

 shape and relative proportions as those of B. pulchra. A preneural 

 is present as in Chisternon, The form of these bones is well shown 

 in figure 9. The costals are rather uniform in width so far as they 

 can be determined. 



The carapace has a greatest length at the center of 442 mm and a 

 greatest width of 375 mm. The lateral borders posterior to the 

 inguinal notches thin out 

 to a sharp edge that is 

 shallowly and widely 

 scalloped. 



The sulci outlining the 

 various scutes are plainly 

 impressed, but along 

 either border, owing to 

 faulty preservation, they 

 can no longer be deter- 

 mined. The presence of 

 supramarginal scutes is 

 clearly shown on the for- 

 ward half of the carapace 

 (see fig. 9, 8.711.8.), and 

 the presence of these 

 scutes at once determines 

 the generic affinities of 

 this specimen. There are 

 large supernmnerary cos- 

 tal scutes on each side of 

 the first vertebral (fig. 

 9), as in the other species 

 of the genus and often in 

 other members of the Baenidae. The supramarginal scutes form 

 a row between the costals and the marginals and alternating with 

 them. Although the full boundaries of the supramarginals have 

 not been established, except in one instance, it is quite evident they 

 have greater areal extent than in either of the described species, 

 which has resulted in decreasing the size of the costal scutes. All 

 the costal scutes are longer than broad, whereas in B. pulchra they 

 are broader than long. Whether there was a supracostal scute 

 present on the rear of the carapace, as in B. pulchra (Lambe, 1914, 

 p. 14), cannot be determined in this specimen. 



The nuchal scute is longer than wide, measuring 14 mm on the 

 free border and 18 mm fore and aft. In both B. pulchra and B. 

 albertensis this scute is much wider than long. 



Figure 9. — Carapace of Boremys f/randis. Typp. 

 U.S.N.M. no. 12979. Nl, 2, 3, 4, Neurals 1 to 4 ; 

 nuj nuchal scute ; pren, preneural ; s.m.s., 

 supramarginal scute ; VI and V6, vertebrals 1 

 and 6, respectively. One-sixth natural size. 



