i86 VETERINARY LECTURES 



287. The First Stomach, the Rumen {Plate XX III., A A A A), 

 which is the largest of the four stomachs, and lies on the left side, 

 occupies, in the adult animal, about three-quarters of the whole 

 abdominal cavity. It has strong, muscular bands running in the 

 walls in various directions to assist and control its actions, and is 

 very strong. It is also lined with cuticular membrane, which is 

 studded all over with little projections, or papillae. 



288. The Second Stomach, the Honeycomb (Plate XXIII. , C C), 

 which is the smallest of the four stomachs, is also lined with cuticular 

 membrane, that is pitted all over with little cells, giving it a resem- 

 blance to honeycomb, and is covered with papillae. This stomach 

 acts as a sort of sifting-machine, as in it we find sand, stones, nails, 

 pins, needles, and all sorts of foreign bodies, sifted out of the food 

 before being sent to the third stomach. 



289. The Third Stomach, the Manyplies {Plate XXIII. , D D), has 

 its lining membrane arranged in a peculiar manner, forming a large 

 number of leaves, or folds ; hence its name, psalterium, or omasum — 

 manyfolds, or manyplies. The leaves run lengthwise, and extend 

 from one end to the other, one border being free, while the other is 

 attached to the wall of the stomach. Between the large leaves there 

 are smaller ones, all being covered with small projections, or papillae. 

 The function of this stomach is to press and triturate the food before 

 it passes into the fourth stomach. 



290. The Fourth Stomach, the Abomasum {Plate XXIII., E E), 

 is the true digestive stomach, and in the calf it is much the largest. 

 The interior presents the appearance of large folds, running length- 

 wise over its surface, and this mucous membrane is soft, velvety, and 

 of a pale pink hue. Here the food is chemically acted upon, as 

 described in par. 223 {No. V.). 



291. Rumination, or Chewing the Cud.— This process con- 

 sists of returning the coarsely masticated food, stored in the rumen, 

 back into the mouth, to be there remasticated and properly mixed 

 with saliva. Some portions of the food are returned several times, 



