ROBERT RUSSELL BENSLEY 27 



apparent in sections stained in muchaematein. In such preparations the pyloric-gland 

 cells exhibit a very narrow blue-stained margin along the lumen. The proximal mass 

 of secretion in the neighborhood of the nucleus is either wholly absent or only 

 indicated. In the iron hsematoxylin sections the rest of the cell is found to be filled 

 with cytoplasm free from secretion. The nucleus is full, spherical or oval in outline, 

 rich in chromatin, and separated by a distinct interval from the base of the cell. In 

 size the cell is about the same as the Brunner's gland-cell. The pyloric glands of the 

 porcupine contain numerous cells of StOhr. 



In the guinea pig (Cavia cobaya) the glands of Brunner are feebly developed, 

 although they extend a considerable distance into the duodenum, according to 

 Kuczynski (1890) 10 cm. Even at its thickest part, near the sphincter pylori, the layer 

 may be not more than 0.25 mm. in thickness. For a distance of about 7 mm. it forms 

 a fairly continuous layer of thin lobules, but beyond this point the lobules become 

 very small and occur at increasingly greater intervals. Each lobule is composed of a 

 cluster of branching tubules connected by a short duct with the bottom of a gland of 

 Lieberkuhn. 



The tubules are composed of cuboidal to cylindrical or prismatic cells, varying in 

 height from 9.5 (i in the small flattened tubules of the distal lobules to 14 p to 18 p in 

 the proximal lobules. The nuclei of these cells are irregularly crescentic in shape and 

 are located in the extreme outer ends of the cells. The body of the cell exhibits the 

 usual transparent reticular appearance when examined in preparations stained in iron 

 hsematoxylin. There is usually in the middle of the cell a slight condensation of the 

 cytoplasm, a suggestion of the subdivision of the secretion into two masses. In some 

 of the cells, particularly in those of the ducts near the points where they are about to 

 open into the glands of Lieberkiihn, and in those forming the tubules of the small 

 distal lobules, a very obvious band of this condensed cytoplasm may stretch across the 

 cell. In the latter case the cytoplasmic trabeculae which separate the granules of the 

 proximal mass are coarser in texture and form smaller meshes than those of the distal 

 zone. These facts indicate the probability that the mechanism of secretion in the 

 glands of Brunner of the guinea pig is similar to that in the corresponding glands of 

 the opossum and many other mammals. 



The cells of the pyloric glands immediately adjacent to the pylorus are exactly 

 similar to those of the glands of Brunner. The glands more remote from the pylorus 

 are formed of wedge-shaped cells 12.8/* to 14. 3 p in height, surrounding an extremely 

 small lumen. The nuclei of these cells are spherical or oval in shape and located in 

 the base of the cell. The secretion, which stains readily in stronger muchaematein, 

 occupies a considerable portion of the cell inclosed by the meshes of a cytoplasmic 

 reticulum. In many cells, however, there is a proximal continuous cytoplasmic layer 

 around the nucleus in which may be seen in iron-hsematoxylin preparations large, 

 coarse, rounded granules, concerning the interpretation of which the writer is in doubt. 

 Perhaps they represent an antecedent substance of the mucin. This is the only 



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