INTRODUCTION 425 



direction of the probes a, b. The oesophagus com- 

 municates on one hand with the paunch, i, and on the 

 other, with the cavities, 2, 3, 4 ; and by the aid of a 

 muscular fold formed by the walls of the second cavity, 

 a passage may be formed which leads directly into 

 the third stomach, without communicating with the 

 second. It would therefore seem that the process of 

 rumination is effected in the following manner : The 

 herbage when first swallowed in an unmasticated 

 form passes into the paunch, i, where it accumulates, 

 and undergoes a kind of preliminary mastication. 

 When this paunch is filled, the animal desists from 

 grazing, and the food is again regurgitated into the 

 mouth to undergo that more complete mastication. 

 It then passes into the second stomach, or reticulum, 

 and is there formed into a smooth, lubricated bolus, 

 which being expelled into the oesophagus, is immediately 

 seized by the spiral muscles surrounding that canal, 

 and forced forward into the mouth. After undergoing 

 a thorough trituration, the aliment is again swallowed, 

 and then enters the third stomach. Here it is spread 

 out over the extensive surface formed by the laminated 

 walls of the manyplies, and is prepared for admission 

 into the last or true stomach. 



