U. S. GEOLOGICAL SURVEY 



MONOGRAPH 55 PLATE CXXVI 



JAW REFERRED TO MENODUS PROUTU (TRIGONOCERAS) 



Onc'third natural size. (See p. 524.) British Mus, 4447M. The measurements of this specimen (mi-ms 245 mm.) indicate close 

 specific reference to M. proutii, and it might almo^ be seletfled as a neotype of that species. This jaw exhibits clearly the chief 

 characters of Menodus, The cheek teeth are elongate anteriorly, w^ith heavy external cingula; the canine is compressed and 

 conical with heavy external cingulum; the chin is fuller than in Brontotherium and Brontops. Compare with M. proutii 

 (PI. CXXV), M. trigonocerasl (giganteus?) (PI. CXXXIV), and M. giganteus (PI. CXLI) 



