250 



MAMMALIA. 



FIG. 147. 

 Jaws and Teeth of American Upper Jurassic Multituberculata. (After Marsh.) 



A, B. Ctenacodon potens; right upper jaw, from the inner (A) and oral (B) 

 aspects, four times nat. size, a', first premolar; b, fourth premolar; m, 

 base of zygomatic arch. 



C. Ctenacodon potens; mandibular symphysis, anterior aspect, three times 

 nat. size, a, incisor; r, root of incisor; 1, first premolar. 



D. Ctenacodon serratus (?) ; incisor, anterior aspect, four times nat. size. 



E. Ctenacodon serratus; right mandibular ramus, outer aspect, the small 

 outline nat. size, the drawing four times nat. size, a, incisor; b, condyle ; 

 c, coronoid process. 



F. Ctenacodon serratus; left mandibular ramus, inner aspect, three times nat. 

 size, a, incisor; b, condyle; c, coronoid process. 



G. Allodon fortis; right premaxilla, outer aspect, three times nat. size. 

 s, suture for maxilla; 2, 3, second and third incisors. 



"'*,* 



