1898.] Osborn, Evolution of the Amblypoda. Pari I. 



195 



The presence of the narrow crested C. 

 tvortmani in the Wind River Beds, the 

 highest level in which the genus appears, 

 shows that the two series evolved simultan- 

 eously, just as we observe among the flat- 

 tened and crested Eocene Titanotheres. 

 In each the evolution uf the molar crests 



from oblique to transverse angles, with degeneration of the ento- 

 conid, loss of crescents, etc., was apparently parallel. 



The sex characters, as clearly shown in numerous specimens 

 of C. testis, are : Males larger, with ])owerful upper and lower 

 canines ; females smaller, with smaller upper and lower canines. 

 (See Fig. 17.) 



