322 PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



being conducted by means of the oesophageal gutter. The amount so 

 conducted must, in the most favorable cases, be but insignificant, since 

 the oesophageal gutter is not a direct continuation of the gullet, but 

 joins it in an oblique angle directed toward the right side. The 

 explanation of the origin of the large amount of fluid invariably found 

 in the first and second stomachs would otherwise be impossible, for, as 

 already pointed out, the lining membrane of these two compartments is 

 but sparsely supplied with glands, and, therefore, they are incapable of 

 furnishing a secretion of their own. 



The opening between the second and third stomachs is extremely 

 small. Coarsely comminuted food is therefore incapable of passing into 

 the manyplies, and accumulates in the first two reservoirs. The rumen 

 and honey-comb bag invariably contain food, even after animals have 



Fig. 139.— Stomach of the Newborn Lamb, Dried and Inflated ; Two- 

 Fifths the Natural Size. (Tlianhoffer.) 



B, rumen; R. reticulum: S. omasum : O, abomasum ; c, cardia; p. pylorus; 6, (Esophagus; eft, 

 cardial valve ; bv, oesophageal canal ; r, folds in rumen ; m, opening into reticulum ; on, opening into 



abomasum ; it, blood-vessels ; e, duodenum. 



fasted for twenty-four hours. Thus, Colin found that in an ox which 

 had fasted twenty-four hours the rumen might contain one hundred and 

 fifty to two hundred pounds of food, three-fourths of which was water, 

 but little solids being found in the reticulum. 



The coarsely ground food which first enters the paunch and reticu- 

 lum is subjected there for a variable time to the liquids contained in 

 those organs, — saliva, mucus, and water ; in proportion to the different 

 nature of vegetable food is its presence in the rumen prolonged. Liquids, 

 such as milk, which need no second mastication, pass chiefly into the 

 second and third cavities. The functions of the rumen are then dis- 

 pensed with, and, as a consequence, we find the rumen quite rudimentary 

 in suckling herbivorous animals (Figs. 138 and 139). The reaction of 



