SOUTH DAKOTA SCHOOL OP MINES 87 



Dinictis, with its less powerful canines, doubtless preyed 

 more successfully on the smaller swift-footed animals, the 

 securing of which demanded superior speed and endurance. 



Figure 32 — Skeleton of the Oligocene saber-tooth tiger Dinictis 

 squalidens. Matthew, 1901. 



The White River badlands furnished the earliest dis- 

 covered remains of Saber-tooth cats in America. Leidy who 

 described the first species gave it the name Machaerodus 

 primaevus. Later this was changed to Depranodon prim- 

 aevus, and still later to Hoplophoneus primaevus, the name 

 it now bears. From time to time other species have been 

 discovered until now about a dozen are known. They were 

 all most terrible beasts of prey and one of them Eusmilus da- 

 kotensis, approaching the size of the African lion was the 

 largest carnivore of its time. 



MUSTELIDAE 



The Mustelidae of the present day include such animals 

 as the badgers, minks, martens, weasels, ermines, skunks, 

 otters, and ratels- Fossil members of the family have been 

 found in some abundance. The more ancestral forms con- 

 tinue back to Eocene time, but no clearly defined species 

 have as yet been identified in the White River badlands in 

 rocks older than the Miocene. 



None of the remains discovered are complete, and nearly 

 all are more or less mutilated. Those of Megalictis ferox, 

 however, are sufficiently characteristic to indicate much of 

 the nature of the animal. They represent a very large mus- 

 teline. The head is short, wide, and massive, brain small, 



