78o 



GEORGE WAGNER 



other characters of the various skulls so far figured, has con- 

 vinced me that P. leptorhiims Williston is a synonym of P. com- 

 pressus, as the author believed to be probable (1896, p. 303). 

 There would seem to be little doubt that the differences given 

 between these eastern and western specimens are merely indi- 

 vidual. I am further convinced of this by Leidy's comments 

 upon the variations in the skull of Dicotyles torquatus and by the 

 differences shown in the dentition of specimens of Dicotyles and 

 Platygonus. 



Fig. 3. — Platygonus conipressus Lee. Lower jaw of adult male. 



Platygonus compressus, therefore, seems to have had a very 

 wide distribution during Pleistocene times in North America,, 

 ranging at least from New York to the extreme west of Kansas^ 

 and from Michigan to Mexico. 



It will be of interest here to note some of the other related 

 forms described from North America : 



PlatygoTius striatus M.diYsh (1871). The type consists of por- 

 tions of two lower jaws from the "Pliocene" (Pleistocene?) of 

 Nebraska, with a few anterior teeth. The characters distinguish- 

 ing this from P. compressus do not seem to be important. 



Platygo?ius co7idoni Marsh (1871). The type consists of por- 



