XXIV.] THE STOMACH. 267 



one common duct. The duct is short, and is lined by cells like 

 those covering the surface of the stomach. The secretory part of 

 each gland is lined throughout by a layer of polyhedral or short 

 columnar, granular, nucleated cells, called chief, principal, inner, 

 or adelomorphous cells. At intervals between these and the base- 

 ment membrane of the gland are large, ovoid, conspicuous, granular 

 cells outer, parietal, delomorphous, or oxyntic. The lumen of 

 the gland is small and ill-defined. 



The pyloric mucous membrane is beset with pyloric glands, 

 which have a long duct or neck, and are usually branched at their 

 lower ends. The duct is lined by a layer of cells like those lining 

 the stomach, and the secretory part by a single layer of short, finely 

 granular, short columnar cells. The lumen is well-defined. There 

 is more connective tissue between the glands than in the cardiac 

 portion. Masses of adenoid tissue are not unfrequently seen 

 between the bases of the pyloric glands. 



Methods. (i.) Select a cat or dog that has hungered for two 

 days. Kill the animal, open the stomach, and place small parts of 

 the cardiac and pyloric ends (all the coats) in equal parts of chromic 

 acid (J per cent.) and spirit (7-10 days). Change this fluid w r ithin 

 twelve hours. Complete the hardening in alcohol. 



(ii.) Place small pieces of the cardiac and pyloric mucous mem- 

 brane (J inch cubes) in i per cent, osmic acid (24 hours). Wash 

 well and harden in alcohol. 



(iii.) Fix pieces of the pyloric and cardiac mucous membrane 

 in mercuric chloride (2-3 hours). Take care to remove all the salt 

 by prolonged washing in alcohol. Perhaps this is one of the best 

 methods to use. 



(iv.) Absolute alcohol is also a good hardening medium. 



To bring out all the chief characters of the glands, some sections 

 are to be stained in logwood and mounted in balsam. The sections 

 may be cut by freezing or in paraffin, after staining in bulk. Stain 

 otkers in picro-carmine, and mount in Farrant's solution ; others in 

 dilute carmine (24 hours). Stain others with i p.c. watery 

 solution of aniline-blue (Nicholson's No. i) for twenty minutes. 

 AVash in glycerine and water, and mount in Farrant's solution. 

 For other methods (p. 271). 



1. V.S. Cardiac End. (a.) (L) Observe the relations, relative 

 thickness, and structure of the several coats. The mucous coat, 

 with its gastric or cardiac glands, or glands of the fundus, set 

 vertically like so many tubes in a rack (fig. 256). The glands are 

 simple tubular glands, and some of them have several secretory 

 parts opening into one duct ; at their bases is delicate connective 

 tissue, adenoid tissue, and blood-vessels. Below the closed ends 

 of the glands, in the cat, a clear homogeneous layer of condensed 



