ORGANS ANNEXED TO THE ABDOMINAL DIGESTIVE CANAL. 419 



qi:antities at short intrrvals, the stomach, properly called, can only be a temporary 

 receptaclc for the aliment, which passes rapidly through it after being impregnated by the 

 gastric juice. The surface which secretes that fluid is also singularly reduced, because 

 if it has to perform its functions more frequently than in Carnivora, it is not required to 

 display so much activity in a given time. If, on leaving the stomach, the alimentary 

 matters encounter a vast intestinal surface, it is in order that the repaiative materials 

 dispersed in the alimentary mass may not escape the absorbent action of that surface, 

 and may be the more effectually brought into contact with it. We have this exemplified 

 in Ruminants ; owing to their double mastication and the triturating action of the many- 

 plies, their food arrives in the stomach proper more comminuted and better attenuated 

 than in the Horse ; the mass, more finely broken up, retains less of the assimilable and 

 reparative matters, and these are more easily seized by the absorbing surface ; and, as a 

 necessary consequence, the intestinal tube, although longer than in Solipeds, is far from 

 offering the same capacity. 



Analogous considerations explain the reason for the intermediate conformation of the 

 digestive canal in Omnivorous animals. 



There is, then, an admirable correlation between the conformation of the digestive 

 tube and the nature of the substances which form the base of the alimentation of animals ; 

 and this harmony is equally apparent when the stomach and intestines are compared with 

 the other apparatus of the economy, and with the natural habits and instincts of creatures. 

 So it is that a creature furnished with an ample stomach and narrow intestine, will have 

 sharp teeth and claws to tear its prey, strength and agility to capture it, and will also 

 possess sanguinary instincts , while another, with its gastric surface greatly diminished, 

 will have intestines as developed in Iheir length as in their capacity, and be dislinguished 

 by its peaceful habits, the absence of aggressive claws, and the crushing and grinding form 

 of the principal pieces of its dental apparatus, etc. 



ORGANS ANNEXED TO THE ABDOMINAL PORTION OF THE DIGESTIVE 



CANAL. 



These organs are three in number : two glands the liver and pancreas, 

 which pour into the small intestine two particular fluids, the bile and pan- 

 creatic juice ; and a glandiform organ, the spleen, remarkable for its nume- 

 rous vascular connections with different organs of the digestive apparatus, 

 and which for this reason deserves to be studied with it, although it is 

 doubtful, if not improbable, that it has anything to do with digestion. 



Preparation. These three organs can readily be studied after removing the intestinal 

 mass, as indicated at page 385. In order to examine the details of their organisation 

 with more facility, it would be well to detach them altogether with the diaphragm and 

 kidneys, and to lay out the whole on a table. (To study the relations of these three 

 organs with those of the abdominal cavity, it is advisable to place the subject on its 

 sternum after removing the intestines, and to detach the posterior part of the body at the 

 loins.) 



The Liver. (Figs. 182, 211, 216.) 



Situation Direction,- This organ is situated in the abdominal cavity, to 

 the right of the diaphragmatic region, and in an oblique direction down- 

 wards and to the left. 



Weight. The weight of the healthy liver, in a middle-sized Horse, is 

 eleven pounds. 



Form and External Surface, Eeleased from all its connections with the 

 neighbouring organs, and viewed externally, it is seen to be flattened before 

 and behind, irregularly elongated in an elliptical form, thick in its centre, 

 and thin towards its borders, which are notched in such a manner as to 

 divide the organ into three principal lobes. This configuration permits it 

 to be studied in two faces and a circumference. 



The anterior face is convex, perfectly smooth, and channeled by a wide 



