464 



THE DIGESTIVE APPABATUS IN MAMMALIA 



These cavities represent a considerable mass that fills the greater part of the abdominal 

 cavity, and the mediniu capacity of which is not less than lit'ty-five gallons! One of them, 

 the Rumen, into whicli the ojsophagus is inserted, constitutes niiie-tentiis of the total mass. 

 The other three, the Utticulum, Omaaum, and AhoiiKisum, form a short chain, continuous with 

 the left and anterior portion of the rumen. The abomasum alone should be considered as a 

 true stomach, analogous to that of the Dog, or the right sac of the ventriculus of Solipeds. 

 The other three compartments only represent, like the left sue in the latter animals, oesopha- 

 geal dilatations. 



The description about to be given of each of these divisions more particularly applies tc 

 the Ox; care will be taken, in the proper place, to note the special peculiarities in the stomach 

 of the Sheep, Goat, and Camel. 



Rumen (Figs, 268, 271). — This reservoir, vulgarly designated the paunch, alone occupies 

 three-fourths of the abdominal cavity, in which it aflfects a direction inclined from above to 

 below, and from left to right. 



External conformation. — Elongated from before to behind, and depressed from above to 



Fig. 268. 



STOMACH OF THE OX, SEEN ON ITS RIGHT UPPER FACE, THE ABOMASUM BEING DEPRESSED, 



A, Rumen, left hemisphere; B, rumen, right hemisphere; C, termination of the oesophagus; 

 D, reticulum ; E, omasum ; F, abomasum. 



below, it offers for study : 1. An inferior and a superior face, nearly plane, smooth, and divided 

 into two lateral regions by traces of fissures, whicli are (jnly sensible at the extremities of the 

 organ. 2. A left and right border, smooth, thick, and rounded. 3. A posterior extremity, 

 divided by a deep notch into two lobes, described by Cliabert by the name of cnniral cysts. 4. 

 An anterior extremity, offering an analogous arrangement, and concealed, at first sight, by the 

 stomachs (or compartments) superadded to the runic n ; the notch on the right of this extremity 

 divides it into two unequal pouclies, which will be referred to presently. 



It is to be remarked tlmt these two notches, which are prolonged on the surface by furrows 

 that separate these into two lateral regions, divide the rumen into tv:o sacs-n rigid and left; 

 this division we shall find more manifest in the interior of the viscus. The right sac — the 

 shortest — is in great part enveloped by the serous covering which constitutes the grent omentum. 

 The left sac surpasses the other by its two extremities, except in the Sheep and Goat (Fig. 

 271), in which the right conical cyst is longer than the left. The anterior extremity of this 

 left sac is thrown back on the corresponding lobe of the right sac ; above, it receives the 

 insertion of the oesophagus, and is continuous, in front, with the reticulum. 



