BRANCH CHORD AT A: CLASS MAMMALIA 



395 



camels, pigs, and hippopotami. The Artiodactyls com- 

 prise two groups, the Ruminants and Non-ruminants. 

 All of the native Ungulata of our Northern States belong 

 to the Ruminants, so called because of their habit of 



chewing a cud. A ruminant first presses its food into a 

 ball, swallows it into a particular one of the divisions of 

 its four-chambered stomach, and later regurgitates it into 



