422 ANATOMY OF VERTEBRATES. 



fringed margin. The Lemmings have a similar type of stomach , 

 complicated with a slight subdivision, fig. 319, c, of the right com- 

 partment, near the pylorus, where the thicker glandular lining 

 graduates into the thin smooth mucous membrane of the supra- 

 pyloric sac, e. From the cardiac orifice a pair of ridges curve 

 toward the pyloric division, defining a groove or canal, /, ana- 

 logous to that which will be shown in the Ruminants ; the border 

 of the epithelium of the cardiac half is well-defined and some- 

 times fringed. The gastric tubes of the compartment, b, are so 

 complex as to give the character of a gland to the lining mem- 

 brane. 



In the Beaver ( Castor) the stomach is transverse and elongated 

 in that direction, the right portion being larger than that which 

 is situated to the left of the cardia ; the oesophagus is inserted 

 into the first third of its anterior margin by a narrow opening, 

 surrounded with pointed processes, which are analogous to the 

 fringes formed by the epithelium in many other Rodents. On 

 the right of the oesophagus, at the lesser curvature of the stomach, 

 is a gastric gland composed of numerous branched follicles, the 

 blind ends of which, when exposed by removal of the muscular 

 coat, give the gland a lobulated surface : the orifices of the glands 

 are arranged on slight ridges in three longitudinal rows on a flat 

 tract of the inner surface. On the right of these orifices com- 

 mences the pyloric portion, the termination of which is indicated 

 by an external constriction, and by an internal thickened ring : 

 the pylorus is approximated to the cardiac orifice. This pyloric 

 portion, which is more muscular than the rest, is sometimes 

 dilated into a distinct pouch, separated by a constriction from the 

 pyloric cul-de-sac. The internal membrane presents everywhere 

 the same appearance, except that in the pyloric portion it appears 

 to be more smooth, and its folds take a different direction. On 

 the right of the cardia there is a very thick fold, separating the 

 left from the right compartment. In the Dormouse (Myoxus 

 gits) and Muscardine (M. avellanarius) similar follicular glands 

 are aggregated round a dilated termination of the oesophagus, or 

 cardiac commencement of the stomach, like the ' proventriculus ' 

 of birds. 1 We have here a repetition of the structure noted in 

 the Wombat. 



In the Cape Mole {Bathyergus) the abdominal oesophagus is 



an inch in length and terminates midway between the two ends 



of the stomach. The right compartment is of enormous size, 



elongated and pierced at its base by the cardiac orifice ; the left 



1 xx. vol. i. p. 181, No. 590 a. 



