34 



BULLETIN 110, UNITED STATES NATIONAL MUSEUM. 

 Measurements of axes, Antrodemiis valens. 



Greatest length of centrum 



Greatest width of anterior extremity. 

 Greatest width of posterior extremity 



Greatest height over all ... ; 



Least width of centrum 



No. 8367, 

 U.S.N.M. 



No. 4734, 

 U.S.N.M. 



74 



65 



215 



32 



85 



50 



53 



173 



25 



Cervicals posterior to the axis. — ^All of the cervicals posterior to the atlas and 

 axis were found disarticulated, but the complete series was recovered and in an 

 excellent state of preservation. 



Fig. 18. — Articulated cervical vertebrae of Antrodemus valens Leidy, No. 8367, U.S.N.M. Viewed from the right 

 SIDE J NAT. size. 01, AXIS; HI. in, axis intekcentrum; o, odontoid; 3, 4, 5, 6, 7, S, 9, cervical vertebrae three to 



NI.\E KESPECTIVELT. 



In all, counting back from the skull there were nine vertebrae and these prob- 

 ably represent the entire cervical series as corroborated by specimen No. 8367, 

 U.S.N.M., shown in figure 18. The remaining 14 presacrals were found articulated. 

 This specimen therefore is in perfect accord with No. 666 of the American Museum 

 of Natural History, New York, which has 23 vertebrae ui the complete presacral 

 series. 



The third cervical may be distinguished by the sharp longitudinal keek on the 

 ventral side of the centrum, all others including the atlas and axis, having this 

 portion of the centrum smoothly rounded. 



