SUCCESSIVE MAMMALIAN FAUNAS 



271 



Fig. 140. — Some characteristic mammals of the Bridger Eocene reduced to a uniform 

 scale, with a pointer dog, in frame, for comparison. 1. Primitive rhinoceros 

 (tHyrachyus eximius). 2. iTritemnodon agilis. 3. tPatriofelis ferox, and 4, fDro- 

 mocyon velox, 'tcreodonts. 5. Primitive rodent (jParamys dclicatior). 6. iUintathe- 

 rium alticeps. 7. fTitanothere {iMesatirhinus superior). 



a modern tapir in stature and was not dissimilar in appearance. 

 These Bridger ftitanotheres were considerably smaller than 

 those of the Uinta and therefore very much more so than the 

 White River forms ; it was not till the latter stage that the 

 family lived up to its name of ''titanic beasts." By far the 



