668 



COLLEGE ZOOLOGY 



The term ruminant has been given to the animals belonging to 

 the camel, chevrotain, deer, giraffe, pronghorn, and ox families, 

 since they ruminate or chew their cud. The food of these ani- 

 mals is swallowed without sufficient mastication; it is later re- 

 gurgitated in small quantities and thoroughly chewed. This 

 method of feeding enables " these comparatively defenseless ani- 

 mals to gather nutriment in a short time and then retreat to a 

 safe place to prepare it for digestion." A typical ruminant pos- 

 sesses a stomach consisting of four chambers (Fig. 535): the 



e ' 



FIG. 535. Stomach of a ruminant opened to show internal structure. 

 a, oesophagus; b, rumen; c, reticulum; d, psalterium; e, abomasum; /, duo- 

 denum. (From Flower and Lydekker.) 



first two, the rumen (b) and the reticulum (c), belong to the 

 cardiac division; and the other two, the psalterium (d) and the 

 abomasum (e), belong to the pyloric division. The food is first 

 taken into the rumen (b), where it is moistened and softened; it 

 passes back into the mouth as " cuds " and is ground up by the 

 molar teeth and mixed with saliva. When the cuds are swal- 

 lowed, they are received by the reticulum (c) , then pass into the 

 psalterium (d), and finally into the abomasum (e). 



The peccaries (TAYASSUID^E) are pig-like animals confined to 

 America. They possess large, prominent canine teeth, and in- 

 cisors in both jaws, but are without horns. The Texas peccary, 

 Tayassu angulatum, occurs in Texas. It looks like a small black 



