PLATYGONUS COMPRESS US LECOA TE 



781 



tions of two maxillae with three posterior molars, from the "Plio- 

 cene" (Pleistocene?) of Oregon. Cope and VVortman (1884) 

 referred this to Dicotyles. The posterior molar is larger than in 

 P. compressus (26™'"). 



Platyg07ius rex Marsh (1894). Based upon three lower teeth 

 from the "Pliocene" of eastern Oregon. Gidley (1903) says 

 "the horizon is almost certainly Upper Miocene." If so, there 

 will be no question of the validity of the species. The last 

 lower molar has a length of 27"™. 



FiF. 4. — Platygonus compressus Lee. Lower of jaw adult male 



In addition, other species referred to this genus have been 

 described by Marsh (1871, P. striaius, Eocene of Wyoming), 

 Cope (1894, P. calcaratus, Blanco beds of Texas), and Gidley 

 (1903, P. texa?tus, Blanco Pliocene of Texas). In comparing P. 

 veins and P. alemanii, it is noticed that the two species, if they 

 are distinct from each other, are of larger size than P. compressus, 

 and they may represent a species distinct from the latter, with 

 practically the same geographical distribution, and they were 

 probably contemporaneous. 



Some years ago Newberry (1875, P- 6) nientioncd a lot of a 

 dozen nearly complete specimens of Platygonus compressus, found 

 within the city limits of Columbus, O., and belonging to the 



