Marsh Collection, Peabody Museum. 



379 



preserved with the skeleton, but not being in place, it is not 

 absolutely certain just how they should be arranged. They 

 are so strikingly different from the narrow elongate sternals of 

 any of the modern Carnivora, that, were they found separately, 

 one would scarcely suspect that they belonged to an animal of 

 this order. On comparison with the corresponding bones of 

 the Marsupials, however, especially those of an opossum, 

 figure 46, they are seen to bear a very decided resemblance, — 

 so marked, in fact, that I have no hesitancy in arranging them 

 after this species. The presternal piece is missing as well as 



45 46 



of Dromocyon vorax Marsh ; one- 



Figure 45. — Ventral view of the sternum 

 fourth natural size. (Type.) 



Figure 46. — Ventral view of the sternum of an opossum, Didelphys virginana ; 

 natural size. 



the xiphisternum, but apparently all the mesosternal segments 

 are represented. The anterior one of these is long and narrow, 

 but the succeeding ones widen rapidly and become characteris- 

 tically broad and flat. There is evidence of five of these pieces, 

 the last being the widest, as in the opossum. This latter seg- 

 ment has a thickened ventral keel which is confined to the 

 posterior end ; its truncated extremity furnishes a thickened 



