PROCEEDINGS OF THE CANADIAN INSTITUTE. I3 



Among mamiiaals, I have found the cat most suited to experimental research, 

 on account of the large size of the zymogen granules, and in this preliminary paper 

 I will confine myself to an account of the results attained by observation of the 

 gastric glands of this animal in various stages of secretion, and reserve for the 

 full paper, to be published shortly, the confirmatory facts elicited from an examina- 

 tion of the stomachs of other mammals, fishes, amphibia, and reptilia. 



The chief cells of the fundus glands may be divided into two groups, those of 

 the body and those of the neck of the gland. The differences between these two 

 kinds of cells will be minutely described. 



If the fundus glands of an animal that has fasted for twenty-four hours be 

 hardened in the alcoholic sublimate bichromate mixture, the chief cells present the 

 following characters: — They are cubical or pyramidal in shape, the base of the 

 pyramid being usually directed towards the lumen of the gland. In preparations 

 stained in haemalum and eosin, the body of the cell is found to contain a network 

 of large polygonal meshes of equal size, and pervading the whole cell. In secretions 

 stained in saffranin, or gentian violet, or the iron alum haematoxylin of Heidenhain, 

 the cell is filled with granules of large size, the zymogen granules. In the Ehrlich- 

 Biondi mixture the network stains red, and it is then seen that each mesh of 

 network corresponds to a zymogen granule. The apparent network is really the 

 optical section of the partitions between the spaces in which the zymogen granules 

 lie. The nuclei are round or oval, occasionally slightly irregular, and placed near 

 the base of the cell. They possess a well-defined chromatin network, and one or 

 two large eosinophilous nucleoli. I have directed considerable attention to the 

 structure of the nuclei in the different phases of secretion, with a view of determining 

 if changes similar to those described by Platner, Ogata, and others in the nuclei of 

 the pancreatic cells are to be observed in the gastric chief cells. So far, however, I 

 have been unable to demonstrate any changes, with the exception of the slight 

 irregularity of outline sometimes seen in the resting cell. This, I feel inclined to 

 attribute, rather to compression by the secreted products, than to spontaneous 

 •change of form. 



In an animal that has been continuously digesting for a period of six hours 

 the chief cell is distinctly marked off into two zones. The inner zone is still filled 

 with large granules, between which may be seen in Ehrlich-Biondi stained sections, 

 the red stained meshwork of hyaline protoplasm. The outer portion of the cell 

 contains no granules, but is occupied largely by a substance which has a peculiar 

 afifinity for nuclear dyes, such as haematoxylin. This substance possesses an 

 obscurely fibrillated structure, the fibrillae being placed side by side in the base of 

 the cell, so that one is at first reminded of the appearance of the striated epithelium 

 of the intralobular ducts of the salivary glands. On closer examination it may be 

 seen that the fibrillation in the outer portion of the chief cell is not so regular, nor 

 are the fibrillae as distinct from one another as in the salivary ducts. The fibrillae are 

 also of larger size, and irregularly swollen at intervals so as frequently to mask the 

 fibrillated structure. The form taken by this substance in the base of the cell, 

 particularly when it is present in small amount, frequentlv reminds one strongly of 

 the figures published by Macallum,'° Eberth, and Mueller," and others, of the 

 tiebenkerne in the pancreatic cells of the amphibia, and one is led to inquire if these 

 structures are not of similar nature. The amount of this fibrillated substance in 

 the cell, under normal conditions, varies inversely with the number of zymogen 

 granules, and one can only conclude that the chromophile substance in the base of 

 the cells breaks down during rest, and thus takes part in the formation of zymogen 

 •granules, which is then actively progressing. Mouret'^ takes a similar view of the 

 nature of the chromophile fibrillated substance in the outer portion of the 



(10) Transactions of the Canadian Institute. Vol.1 1890. 



(11) Zeltschrift f. Wissenschaft. Zool. Bd. 53. Supplement. 



(12) Journal de 1' Anatomie. 1895. 



