SINCLAIR: MARSUPIALIA OF THE SANTA CRUZ BEDS. 



POLYPROTODONTIA. 



THYLACYNID&. 



The Santa Cruz thylacynes are short-legged animals, with large heads, 

 long necks and heavy tails. These characters are well shown in the 

 accompanying restorations of Prothylacynus patagonicus and Cladosictis 

 lustratus (PI. LXI, figs, i, 2). In order to show clearly the points 01 



FIG. i. 



>. . : 



\ 



a b c d * 



Thylacynus cynocephalus. a, right humerus, front view ; b, right radius and ulna from the 

 outer side ; c, right femur, front view ; d, right tibia, front view ; c , right fibula from the inner 

 side. All figures x . 



agreement between the various Patagonian genera and Tkylacynus, and 

 the respects in which they differ, the following summary has been intro- 

 duced : 



i. In all, the facial region of the skull is short in proportion to the 



