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The rwroti is a sac where the aliment taken during ft eding-time is kept in reserv--, 

 nnd whence it is again carried into the month during rumination, after having been 

 more or leas softened. 



The reticulum paiticipates in the functions of the rumen, to which it is only a kind 

 of diverticulum. But it is particularly with regard to liquids that it plays the part <>t u 

 reservoir; the solid substances contained in it being always diluted by u large quantity 

 of water. 



The cetophageal groove carries into tlio omasum the substances swallowed a soruii'I 

 time after rumination, or even those which the animal ingests in very smull quantity t'r 

 the first time. 



The oiiinniiin completes the trituration and attenuation of the food, by pressing it 

 between its leaves. 



The abomagum acts as a true stomach charged with the secretion of the gastric juice ; 

 in this reservoir occur the essential phenomena of gastric digestion. 



COMPARISON OF THE STOMACH OF MAX WITH THAT OF ANIMALS. 



In its form, the stomach of Man much resembles that of the Carnivora. 



The insertion of the oasophagus, however, does not offer so large an infundibulum. 

 The organ is situated in the left hypochondriac, and is nearly horizontal. 



Everywhere the mucous membrane is red and glandulitr; the muscular fibres are 

 disposed in three planes, as in Soliptds ; but the sdpeificial and deep are particularly 

 directed towards the left sac. 



THE INTESTINES. (Figs. 204, 205, 206.) 



The alimentary canal is continued from the stomach, in the abdominal 

 cavity, by a long tube doubled on itself a great number of times, and which 

 terminates at the posterior opening of the digestive apparatus. This tube is 

 the intestine. Narrow and uniform in diameter in its anterior portion, which 

 is named the small intestine, it is irregularly dilated and sacculated in its 

 posterior part, the large intestine. These two portions, so markedly defined 

 in all the domesticated mammals, are biit imperfectly distinguished from one 

 another with regard to the digestive phenomena occurring in their interior. 

 We will study them in all the animals which interest us, and conclude by a 

 general and comparative examination of the entire abdominal portion of the 

 digestive canal. 



Preparation. The study of the intestines does not demand, properly speaking, any 

 special preparation; it being sufficient to incise the inferior wall of the abdomen to 

 expose these vie -era. As their mass, however, is heavy and unmanageable, it is 

 arlvi.-able to expel their contents in a manner similar to thnt recommended for the 

 preparation of the stomach ; a puncture at the point of the cecum allows the escape of 

 the substances ac.-umulated in that reservoir those which fill the largo colon may In- 

 removed by an incision made towards the pelvic curvature, and those in the floating colon 

 by the rectum. The small intestine may be evacuated by three or four opening ;r 

 about equal distances in the length of the viscus. Having d<>;ir this, inflate the 

 intestines to somewhat of their natural volume; th s propitiation then perm ts the 

 general arrangement of the intestinal ma-s in the interior of the abdomen to be easily 

 studied. 



It would be well to remove the entire mass altogether fioin the body, and lay it out on 

 a table, so as to isolate the various parts, study them in succession, and note their iorm. 



1. The Small Intestine. (Figs. 204, 205, 206.) 



Length Diameter. The small intestine is a long tube, which, in a Horse 

 of ordinary height, may average about 24 yards in length, and from 

 1 to If inches in diameter. This diameter is susceptible of variation, 

 according to the state of contraction of the muscular tunic of the viscus. 



Form. This tube is cylindrical, doubled on itself, and presents two cur- 

 vatures : one convex, perfectly free ; the other concave, called the small 

 curvature, which serves as a point of insertion to the mesentery that sustains 



