44 zooLOGy. 



Order : Ruminantia (Cud-chewixg Mammals). 



The feet end in two hoof-covered toes, besides which 

 two "after toes" are present. The upper incisors are 

 absent, with few exceptions, but many deer have 

 canines in the upper jaw. The back teeth of Rumi- 

 nants are compound teeth. The lower jaw is smaller 

 than the upper, and during chewing undergoes lateral 

 movements, so that the plants taken in as food are 

 ground up, as it were, into small pieces, between the 

 projecting enamel ridges of the upper and lower back 

 teeth. The stomach consists of four subdivisions ; 

 these are (1) the rumen, or paunch, where the greater 



Fig. 26 Skull of a Sheep. 



part of the food and water taken collects; (2) the 

 reticulum, or honey-comb stomach ; (3) the psalterium, 

 or manyplies; (4) the abomasum, reed, or rennet 

 stomach. The last is the second largest part, and in 

 it the same chemical changes take place as in the 

 simple stomach of a non-ruminant. After the food 

 has remained for some time in the paunch it passes 

 up again through the gullet, and [as the " cud "] under- 

 goes a second chewing. The soft mass resulting is 

 once more swallowed, and passes into the psalterium 

 and abomasum. 

 Not only the families of Tylopoda (Camels, Llamas), 



