xxxi. 4 



PIGS AND PECCARIES 



749 



in families or small troops. A large number of young are produced 

 and the male produces a great volume of semen. Sus is mainly an Old 

 World genus, found from the Miocene onwards. It was represented 

 in Great Britain by the wild boar, common until the sixteenth cen- 



FiG. 494. Skeleton of the pig. (Modified after Ellenberger from Sisson 

 and Grossman, Anatomy of Domestic Animals, 3rd edition 1938, published 

 by W. B. Saunders Company, Philadelphia.) 



Fig. 495. The wart-hog, Phacochoerus. (From photographs.) 



tury. The African wart-hog (Phacochoerus) (Fig. 495) is not very dis- 

 similar. Potamochoerus is the red river-hog of Africa. The peccaries 

 of Central and South America are similar to the pigs, but have been 

 distinct since the Oligocene. There are two small lateral digits in the 

 fore-foot and one in the hind. A large scent-gland opening on the back 

 resembles a second navel, hence the name, Dicotyles. 



An offshoot of the palaeodont line in the Eocene led to the develop- 

 ment of a race of large amphibious animals, the anthracotheres and 



