GENERAL CHARACTERISTICS. 



75 



place to a new antler. Except in the case 

 of the reindeer only the male deer carry- 

 antlers, and their formation is intimately 

 related to the sexual function. A castrated 

 stag produces no new antlers after the shed- 

 ding of those which it had at the time of the 

 mutilation, or these latter may be permanently 

 retained. Originally all antlers are simple 

 spikes or snags, and it is only in course of the 

 periodical renewals that we see the formation 

 of the lateral shoots or tines, which are 

 sometimes expanded and flattened. 



Notwithstanding the amount of difference 

 between horns and antlers there is yet a 

 connecting link in the American Prong-horned 

 Antelope [Antibcapra americana), the tines 

 of whose antlers are covered with horny 

 sheaths as in the Cavicornia, sheaths formed 

 of a thickened and hardened epidermis or 

 outer skin, but which are shed and renewed 

 several times in the process of growth, fresh 

 ones budding off round the bony cores. 



The structure of the stomach in the pres- 

 ent group is likewise remarkable. It is this 

 which gives rise to the process of rumination. 

 All the members of the group are exclusively 

 herbivorous, and most of them can escape 

 from their enemies only by their fleetness 

 of foot. They accordingly consume great 

 quantities of herbs and leaves with the utmost 

 haste,, filling therewith a capacious compart- 

 ment in their stomach, which serves as a sort 

 of storehouse, and then betake themselves to 

 some retired spot where they can perform 

 the second mastication at their leisure. Since 

 the first mastication is very imperfect and 

 does not suffice for the extraction of the 

 nutritive matter contained in the herbs and 

 leaves, such an arrangement is all the more 

 advantageous, inasmuch as it permits of a 

 more intimate mixture of the food with the 

 saliva. The structure of the stomach is mani- 

 festly due to the necessity for returning to 

 the mouth the material stored up in the large 

 compartment above mentioned in order that 

 it should be finely ground by the action of the 



teeth. The stomach is first divided into two 

 parts, one which serves as a storehouse, and 

 the other which carries on the proper work 

 of digestion. The first part is in direct con- 

 nection with the gullet through the cardiac 

 opening, the second part is continued by the 

 pyloric opening into the intestine. Now 

 each of these parts is again divided into two 



Fig. 157. — The Kanchil [Tragulus pygmceus). page 76. 



subordinate compartments, those of the car- 

 diac portion being the paunch or rumen, 

 which is always very capacious and often 

 forms several secondary pouches, and the 

 reticulum or honey-comb stomach. Into these 

 two compartments the food is first admitted, 

 and from the reticulum it can ascend again 

 to the mouth through the gullet, which is 

 widely expanded for the purpose. But the 

 gullet has throughout its whole length a thick- 

 lipped groove opening into the cavity of the 

 pyloric section of the stomach, which pyloric 

 section is subdivided into the liber, psalterium 

 or manyplies, and the abomasum or rennet 

 stomach. The remasticated food glides down 

 the groove just mentioned, the lips of which 

 shut so as to form a tube, and passes thence 

 directly into the psalterium, and from there 





