PALEOCENE MAMMALS OF CENTRAL UTAH — GAZTN 



35 



deuterocone in P^ of Protogonodon. The posterointernal cingulum 

 is better developed than in Protogonodon^ but not so shelf like as in 

 Tetraclaenodon. 



P^ is somewhat more worn but shows the principal cusp to be 

 slightly less conical than in Protogonodon with a more distinct pos- 

 terior crest. The presence or absence of a tritocone cannot be deter- 

 mined because of wear, but if present it was not developed to the 

 extent seen in Tetraclaenodon. The deuterocone portion is restricted 

 anteroposteriorly more than in Tetraclaenodon^ approaching Pro- 

 togonodon^ but a cingulum not seen in Protogonodon is developed 

 along the anterior and posterior walls of this cusp, separate from 

 the shelf or crest joining the deuterocone to the outer extremities of 

 the tooth. The cingulum and shelf are not developed to the extent 

 seen in Tetra<;laenodon^ nor is there certain evidence of a protoconule 

 or metaconule on the crest; however, wear may have obliterated an 

 incipient development of these. The parastyle, as in Tetraclaenodon, 

 is directed more externally than in Protogonodon. 



»--^ 



Figure 19. — Desmatcclaenus hermaeus, new genus and species: Left upper dentition, 

 including P^, P*, M^, IVP, and right lower dentition, including P3-M1, M3, and part of Mj 

 U.S.N.M. No. 16202), type specimen, occlusal views, X 2, Wagonroad Paleocene, Utah. 



j\P is not preserved in the material of this individual but is 

 included in a maxilla of another and larger specimen, which pre- 

 sumably represents a distinct species and is described elsewhere. 



M- is rather well worn but was evidently low cusped and had a 

 weak hypocone as compared with this tooth in Protogonodon and 

 in contrast to the marked development of the cusp in Tetraclaenodon. 

 However, this cusp is located directly posterior to the protocone 

 as in Tetraclaejiodon^ occupying a position in the flexure between 

 the protocone and metaconule, and not so lingual in position as 

 noted in Protogonodon. The protoconule and metaconule appear to 

 be less developed relative to the primary cusps than in Tetraclae- 

 nodon.^ in wliich the six principal cusps approach equality. In 

 Protogonodon the protocone is more prominent and somewhat over- 



