88 Mammalia, Digestive System. 



one elongated cavity, separated by constriction from the Pyloric 

 portion, which again throws off a small sacculus above ; in Lepus, 

 there is a well-marked tendinous patch on the Pyloric compartment. 



In the Perissodactyh Horse, the thick cuticular lining of the 

 Cardiac Cul-de-sac terminates abruptly by a prominent indented edge, 

 separating it from the Pyloric half with its villous surface. 



In the Omnivorous Arthodactyla. 



In the In-Enamellate Ant Eater, the spherical stomach has a 

 subglobular appendage, as it seems, intervening between the main 

 cavity and the intestine : on both the anterior and posterior sur- 

 faces of the stomach is a sheet of tendon : the Pyloric division is 

 remarkable for the thickness of its muscular tunic, and the^density 

 of its epithelial lining, which convert it into a veritable gizzard. 



(d) has a quasi-glandular Proventeictjlits attached. 



A long glandular proventriculus, separated as in Birds by a con- 

 striction from the wide muscular stomach, is found in Myoxus Avel- 

 lanarius (Kcd Dormouse). 



{e) is Complex. 



In the Artiodactyla the Stomach is generally made up of four 

 distinct cavities, respectively called 1. Rumen, or Ingluvies ; 2. Re- 

 ticulum, or Honeycomb ; 3. Psalterium, Maniplies, or Omasus ; 

 4. Abomasus. The Pv-umcn is the largest of the four cavities, and 

 the reservoir for the food previous to re- mastication : the inner sur- 

 face is covered with papilla? (cuticular villi), except in the Camelidoe, 

 where large cells below and at the sides are found for the retention 

 of water; it secretes an alkaline fluid. The Reticulum, situated 

 directly below the entrance of the oesophagus, always receives the 

 water. The cells vary in depth in different Pamilies, but generally 

 are directly correlated with the nature of the food, being very 

 shallow when {e.g. Giraffa) the food takes the shape of juicy leaves 

 and buds. A passage leads from the oesophagus to the third cavity, 

 bounded by two low parallel ridges. The Maniplies is occupied 

 by deep parallel crescentic folds, like the leaves of a book ; in pass- 

 ing through this the. food is deprived (by squeezing) of superfluous 

 fluid : in the Camelidoe and most Moschidae these longitudinal la- 

 mella? are wanting. The Abomasus has the usual structure of the 

 true digestive stomach ; here the food is penetrated by acid gastric 

 juice ; this is therefore the seat of the true digestion. The Pylorus 

 is protected by a valvular protuberance, placed above it, just within 



