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PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



The second stomach is called the honey-comb bag, or reticulum, and 

 in its histological structure differs but slightly from that of the rumen. 

 Its interior is likewise lined with horny, epithelial cells, arranged in 

 layers, and the inferior layers of the mucous membrane are arranged in 

 similar papillae. The reticulum owes its name to the peculiar arrange- 

 ment of the mucous membrane which lines it in small cells or cavities 

 not communicating with each other, but all opening freely into the 

 general cavity. 



In the camel and llama and other animals of the desert similar 

 collections of cells are found in the rumen also. In these animals they 

 consist of a number of large cells, arranged in parallel rows, and sepa- 

 rated from each other by folds, the free margins of which are thickened 



Fig. 134.— Stomach of Llama. {Colin.) 



A, inferior extremity of the oesophagus ; B, single pillar of the (esophageal canal ; C, superior orifice 

 of the manyplies : D, reticulum ; E, right, or anterior water-cells ; F, inferior water-cells ; G, fleshy 

 column separating the two groups of cells. 



by muscular fibres or sphincters, capable of closing the opening by 

 which each cell communicates with the cavity of the rumen. There are 

 eight hundred of these cells in the camel and dromedary, and they all 

 usually contain water, for which purpose, indeed, they are believed to be 

 constituted. One group of these cells is situated to the left and the 

 other to the right (Fig. 134). These groups of cells are each capable of 

 containing in the camel about five quarts of water. 



The reticulum, or honey-comb bag, is the smallest of the four com- 

 partments, in the ox being fixed above by the oesophagus to the 

 diaphragm, connected with the narrow part of the rumen, and attached 

 below also to the diaphragm. Its cavity communicates freely with that 

 of the rumen by a large opening. 



