NIMEAVID^. 979 



of a skull from the same region. The examination necessary for this deter- 

 mination was kindly permitted me by Professor Guyot. 



The Colorado mandible differs from that of the D. squalidens from the 

 same locality in having a shallow symphysis; that is, it descends but a 

 shoi't distance below the inferior anterior mental foramen. The roots of 

 the first inferior premolar are well separated. The third (fourth) has a 

 well- developed anterior basal tubercle. 



DiNICTIS SQUALIDENS Cope. 



Proceedings Academy Philadelpliia, 1879, p. 176. Daptopkilus squalidma Cope, No. 16, p. 2 (August 20, 

 1873). Annual Report U. S. Geol. Survey Terrs., 1873 (1874), p. 508. 



Plate LXVIIa; figs. 15-16. 



Two mandibular rami belonging to two individuals represent this 

 species. The one on which the species was proposed is immature, with 

 the sectorial tooth partly protruded (fig. 15), and the tubercular invisible. 

 Having failed to find any trace of the latter in the jaw, I proposed to 

 regard the species as typical of a genus distinct from Dinidis, remarking 

 at the time that should such a tooth be ultimately found, the genus would 

 have to be abandoned. Evidence of the existence of this tooth was after- 

 wards obtained. Still later, another saber-tooth was found with precisely 

 the formula supposed to characterize this discarded genus {Daptophilvs). 

 Under the circumstances I thought best to give the former a new name, 

 Pogonodon. 



In this species the first lower molar tooth has but one root, while in 

 the others there are two. The canine tooth of the typical specimen has 

 also a very peculiar form. The crown is short and wide, like that of a 

 Carcharodon shark, or somewhat like that of the saber-tooth Drepayiodon 

 latidens Owen. As the first true molar tooth of this specimen was not fully 

 protruded, it is possible that this canine belongs to the deciduous series. 



The jaw of the adult specimen contains parts of the alveoli of but two 

 inferior incisors; the existence of a third is very doubtful. The canine is 

 larsre and is directed outwards. Its crown is lost. The diastema descends, 

 and is short, not exceeding in length the length of the base of the anterior 

 lobe of the sectorial. The alveolus of the root of the first (second) pre- 



