8 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 9i 



SYSTEMATIC DESCRIPTION OF THE MATERIAL 



MULTITUBERCULATA 



Genus TAENIOLABIS Cope 



TAENIOLABIS species 



The genus Taeniolabis is apparently represented in the collection 

 from the Wagonroad horizon by the posterior half of a first lower 

 molar, U.S.N.M. No. 16172 (fig. 2, a) . In size and appearance the speci- 

 men closely resembles this portion of Mi in Taeniolabis taoensis from 

 the Puerco of New Mexico. The form present in the Wagonroad hori- 

 zon may represent this species, but in the absence of better material, 

 showing at least something of the cusp formula, no specific reference 

 is made. 



Although our knowledge of the history or development of the 

 Taeniolabididae is very incomplete, the presence of Taeniolabis and 

 the absence of Catopsalis in the Wagonroad fauna are significant in 

 indicating a relationship to the Puercan stage. 



In the structure of the molars Catopsalis would appear to be an- 

 cestral to Taeniolahis^ but since their known positions in time are 

 the reverse the two must be regarded as representing separate phyla, 

 and that having the less specialized molars surviving here longer, or 

 reaching this region at a later date. 



Genus CATOPSALIS Cope 



CATOPSALIS UTAHENSIS Gazin 



Catopsalis utahen^is Gazin, 1939b, p. 27."). 



The type of Catopsalis utakensis, U.S.N.M. No. 15757, froih the 

 Dragon horizon, as represented at the principal Dragon Canyon locality 

 (loc. 2 in fig. 1), consists of a single first lower molar (fig. 2, b). 

 The specimen exhibits the simple type of pattern seen in Catopsalis 

 from the Torre j on rather than the more specialized dental structure of 

 the Puerco Taeniolabis. It differs from Mi in specimens of Catopsalis 

 known from the Torrejon of the San Juan Basin in having the cusp 

 formula 6:4. In the type of Catopsalis foliatU'S it is 5 : 4, and in the 

 type of C. f.ssidens the formula is 6:5, or better. Moreover, the 

 tooth is relatively wider than in either of the Torrejon specimens. 

 Catopsalis calgariensls from the Paskapoo was described by Russell 

 from a second lower molar; hence no satisfactory comparison with 

 the type of C. utahensis is possible. 



From additional material of this form collected in 1939 it is seen 

 that the lower molars are distinctly wider than in either C. fissidens 

 or C foliatus. In an Mi (fig. 2, <?), No. 16185, from the upper or 

 Dragon horizon at the new locality (loc. 4 in fig. 1), slightly more 



