l68 BULLETIN OF THE BUREAU OF FISHERIES. 



The basal parts of the cells have fat droplets, but rather smaller in size and not 

 so numerous as in the outer limbs of the cells. 



In certain regions the fat is present in the cylindrical cells of the lining walls down 

 in the deeper folds of the crypts, but in other regions it is entirely absent. I have seen 

 the fat in these cells down as deep into the crypts as the region into which the deepest 

 gastric gland tubes open. In every case there is a very noticeable difference in the 

 amount of fat present in the deep-lying epithelium and the more superficial — always in 

 favor of the greater quantity in the superficial. 



The tubes of the gastric glands open into the sides and bottoms of the crypts. There 

 is a quick transition from the superficial epithelium to the gland cell type at the point 

 where the mouth of the gland opens. It is not often that a section passes longitudinally 

 through the mouth of a gland. This is largely due to the fact that the glands are some- 

 what convoluted in shape, rarely straight and tubular as in the gastric glands of most 

 mammals. A number of gland tubes usually open into each crypt. Some of these 

 are very short, and are only a few cells in length, while others extend quite down to the 

 basement membrane. Occasionally a single tube may be as straight and direct as in 

 the mammalia, but the majority are irregular. The transition in the epithelium from 

 the superficial to the glandular type is sudden and sharp. In medium magnification 

 the superficial epithelium looks darker because of the intense stain (i. e., hsematoxj'lin) , 

 while the gland cells are more clear and granular. 



The gastric glands proper, the differentiated cells of the secreting tubules, seem 

 never to carry fat in other than the finest division. The gland tubes often show a 

 distinct reddish shade of color when stained with scarlet red. In the gastric glands 

 of at least one fish definite droplets were present quite large enough to be conclusively 

 identified as fat of the usual kind and appearance. These droplets appeared to lie 

 near the bases of the cells, and, taken with the numerous finest liposomes present, 

 formed a delicate net-like mosaic. The liposomes were present in greatest numbers 

 in this specimen, no. 88. It seems to me that in this instance the liposomes bear a 

 definite relation to the increased amount of fat present in the cylindrical cells and are 

 to be regarded as absorption fat. 



In preparations of the gastric mucosa of young salmon no. 46, fixed in Flemming's 

 solution, the osmic acid has stained the fat droplets a brownish black, which brings 

 them in sharp contrast with the surrounding tissues. Figure i of a previous brief 

 publication concerning these facts ° shows the superficial epithelial cells of the gastric 

 stomach containing the absorption fat. This black stain in the ends of the cells forms 

 a dense black mass, but it is granular in character. At any rate, where the black masses 

 are broken up granules are seen when examined under the oil immersion. Cross sections 

 of the necks of the crypts present rings of black granular masses around the lumen. 

 These masses are the blackened ends of the cells. Where the section cuts the crypt 

 through the opening of the gastric gland it is noted that the black masses become pro- 

 gressively smaller in the deeper portion of the crypt and are absent from the surface of 

 the secreting gland cells. The cell bodies of the superficial epithelium are stained 

 the dark brown of the osmic fixative. Sections across the cell just beneath the blackened 

 ends present numerous clear areas. These areas are spherical and very small, though 



1 Greene, op. cit. 



