570 EOCENE AND OLIGOCENE PERIODS 



front, and three-toed behind. It had about the size of a small dog, 

 and was as much canine as equine in appearance. True horses did 

 not appear till the Pliocene. 



Artiodactyls emerged from their generalized beginnings more 

 slowly. Suina (pigs, peccaries, hippopotamuses) were represented 

 in the Bridger epoch by a small hog. Strangely enough, the camel 

 family seems to have had its beginning in America in the middle and 

 later Eocene, and to have flourished here until the Pliocene. Then, 



Fig. 47Q. Mounted skeleton of PatriofeMs, a Creodont from the Middle Eocene 

 of Wyoming; 1/18 natural size. (Osborn.) 



having previously sent a branch to South America to evolve into 

 llamas and vicunas, and another into the Old World to become the 

 present camels, the tribe died out in its primitive home. 



Carnivore line. It has been thought by some paleontologists 

 that the creodonts were more primitive than the condylarths, and 

 that the latter diverged from the former, as also the edentates and 

 the rodents. If this is so, it gives the creodonts the central position 

 among the primitive mammals. They lived throughout the period 

 and into the next, gradually giving way to their own more progres- 

 sive descendants. Toward the end of the period, modern types 

 began to emerge definitely from the ancestral forms. Primitive 

 representatives of the dog family appeared in Europe late in the 

 period. Scott states that "clawed mammals long antedated the 



