384 K. R. BENSLEY. 



the gland increases in length. As the pylorus is approached 

 these cells gradually replace entirely the zymogen-forraing 

 chief cell, and the proximal portion of the pyloric region is 

 occupied by short glands, consisting of indulinophilous cells 

 and a few border cells. Ultimately the latter also disappear, 

 and we have the true pyloric gland. 



C. The Gastric Glands of the Dog. 



A section of the fresh mucosa of the greater curvature of 

 the stomach of the dog, examined in aqueous humour, reveals 

 much the same features as a similar preparation of the cat's 

 stomach. The superficial portion of the mucosa, including 

 not only the pits but a large portion of the glands themselves, 

 is entirely free from the zymogen granules that crowd the 

 lower portion of the gland. The granules are smaller than in 

 the cat, and much more difficult to preserve, so that I have 

 been compelled to rely on the examination of the fresh glands 

 for control of my results. 



In sections hardened in corrosive sublimate, or in the 

 bichromate sublimate mixture, the chief cells exhibit the same 

 structural features as those of the cat, namely, a regular mesh- 

 work separating spaces, which one may infer to have been 

 occupied in the fresh cell by the zymogen granules (fig. 11), 

 and in glands from a digesting stomach (fig. 12) of an outer 

 protoplasmic zone, which stains intensely and readily in 

 hseraatoxylin, exhibits a coarse fibrillar structure, and gives, 

 after treatment with sulphuric acid alcohol for three or four 

 hours at a temperature of 37° C, a well-marked reaction for 

 iron. In short, the cell contains both zymogen and prozy- 

 mogen in large amount. 



The chief cells of the neck of the gland, on the other hand, 

 contain no granular zymogen, and only a trace of prozymogen. 

 These cells are of the same nature as in the cat, and present 

 an inner secretion zone of variable extent, which stains intensely 

 in indulin and muchsematein. As in the cat, also, a gradual 

 change in the character of the cells is seen as the surface of 

 the mucosa is approached. 



