SUCCESSIVE MAMMALIAN FAUNAS 



263 



the tLeontiniidse, was highly characteristic of the Deseado 

 fauna and is not known from the Santa Cruz. These were 

 large animals, with a small horn on the tip of the nose and low- 

 crowned, comparatively simple grinding teeth. Even more 

 abundant were the fTypotheria, small forms which were 



Fig. 138. — Horned ttoxodout (iLeontinia gaudryi), Deseado stage. Restored from a 

 skull in the Ameghino collection. 



ancestral to the Santa Cruz genera, larger ones which died 

 out without leaving successors and one quite large animal {'\Eu- 

 trachytherus) which seems to have been the ancestor of the 

 Pliocene and Pleistocene ]Typotherium. This series is not 

 known to have been represented in the Santa Cruz and may 

 have withdrawn from Patagonia at the end of the Deseado stage. 

 The fEntelonychia, those strange toxodont-hke animals 

 with claws instead of hoofs, were much more numerous and 

 varied than they were afterward in the Santa Cruz, when they 



