1898.] Osborii, Evolution of the Ainblypoda. Parti. 1 83 



Family PANTOLAMBDID.^ Cope. 



Genus Pantolambda Cope. 



Dentition typical. First upper premolar one-rooted. Second, third and 

 fourth three-rooted, with internal cones. Canines rounded. 



P . bathniodon. 



Type: Mandibular ramus, No. 3956. 

 Smaller size. Both dental series con- 

 tinuous. 



P . cavirictiis. 



Typt' : Jaw, No. 3961. 



Larger size. First lower premolar 

 close to canine and separated from 

 second by a wide diastema. Pre- 

 molars reduced in size. 



P. cavirictus' Cope. 



The type lower jaw, described and figured by Cope (Am. Nat., 

 Vol. XVIII, p. nil) is peculiar in the close apposition of the 

 first lower premolar to the canine, and the wide diastema behind 

 it. This is the largest type known and the diastema is probably 

 prophetic of the diastema invariably observed in Co/yphodoii, 

 (Fig. 2). 



The skull (Fig. 7) was mistakenly described by Osborn and 

 Earle in 1895 (1895,'^ p. 43) as P. hathmodon. It differs in its 

 much greater size from P. />at/iniodon, and in the absence of dias- 

 temata from the P. caviric/i/s jaw. Unlike Coi yphodon the upper 

 canines are mainly worn upon the inner posterior surface. 



F!g. Q. Skeleton of Pantolambda batkmodon. Scapula wholly, pelvis partly restored. 

 Composition from several individuals. One-eighth natural size. 



> Am. Nat., Vol. XVII, 1883, p. 968. 

 5 Am. Nat., Vol. XVI, 1882, p, 418. 



