NATURE OF RUMINATION. 77 



prairies, and the droves of antelopes on the African 

 veldt. 



Commencing with the function of rumination, we may 

 observe that it is a re-mastication of grass or other 

 vegetable food, swallowed almost as soon as plucked, and 

 transferred to a special receptacle in the stomach. From 

 this it is regurgitated into the mouth by a reversed action 

 of the muscles of the throat, and, after having undergone 

 mastication, or rumination is transferred to the digesting 

 part of the stomach. Now, it is evident that this compli- 

 cated arrangement, so different from that of other animals, 

 must be of some special advantage to the ruminants. As 

 a matter of fact, these animals, like other large herbivores, 

 are obliged to consume a vast quantity of food to obtain 

 sufficient nutriment ; and it is obvious that if this food had 

 to be masticated as soon as plucked, the operation of 

 feeding would be very protracted ; but by the arrangement 

 mentioned the requisite amount of food can be gathered 

 within a comparatively short time, and the animals can then 

 retire to ruminate in concealment. It is superfluous to 

 comment on the advantage of this arrangement to creatures 

 which, like many ruminants, have but little means of 

 defending themselves against carnivorous foes ; but we 

 may mention that many still further increase this advantage 

 by feeding only at dawn or evening, when they are far 

 less conspicuous than in the mid-day glare. There is, 

 moreover, evidence that when ruminants first appeared, 

 this rapid feeding was of more importance than at the 

 present day, since while many of the modern larger forms, 

 like oxen, antelopes, and deer, are provided with formidable 

 weapons in the shape of horns or antlers with which they 

 can keep foes at bay, in earlier times such weapons were 

 either absent or but feebly developed. 



Seeing, then, that the function of rumination is 

 correlated with a special compartment of the stomach for 

 the temporary reception of the freshly-gathered food, it 

 would be expected that animals thus provided would also 

 possess an efficient masticating arrangement for reducing 

 their food to the condition in which it yields the fullest 

 nutriment. Such, indeed, is the case, the grindin^-teeth 



