ROBERT RUSSELL BENSLET 33 



The use of stronger muchsematein which stains intensely the secretion of the cells 

 both of the glands of Brvmner and of the pyloric glands of the rat has enabled me to 

 extend somewhat the description given by Castellant. As the latter points out, the 

 distal (apical) zone of the cell in the rat is remarkable for the extreme tenuity of the 

 fibers of the cytoplasmic network which it contains. It does not, however, contain the 

 whole of the secretion of the cell. In sections stained in muchsematein it may be seen 

 that even cells in the resting condition, in which a large proximal mass of cytoplasm 

 is visible, may contain small granules of stainable secretion, in the portion of this 

 cytoplasm between the nucleus and the deeply stained secretion-filled distal zone of the 

 cell. In some of the cells these granules have so increased in number that the places 

 occupied by them are recognizable in haematoxylin-eosin preparations as clear spaces 

 in this portion of the cell. This appearance marks the transition phase from the rest- 

 ing condition of Castellant's observations to the more loaded condition of the third 

 hour of digestion, and corresponds exactly to what I (1898) have found to be the case 

 under similar experimental conditions in the pyloric glands of the cat. The explana- 

 tion is that the cell when it passes from the resting to the active phase begins to 

 transform rapidly into mucigen the reserve material contained in its basal cytoplasm, 

 the product of this transformation making its appearance in the space between the 

 old secretion and the nucleus. During the first hours of digestion this transforma- 

 tion of antecedent substance into mucigen goes on more rapidly than either the secretion 

 of the mucin from the cell or the repair of the basal cytoplasm from which it is formed. 

 The result is the increase in reserve secretion in the cell. A cell in this condition of 

 maximum loading presents three distinct zones ; a narrow basal zone of protoplasm 

 containing the now slightly flattened nucleus; then the proximal mass of secretion, 

 subdivided by coarse trabeculas of cytoplasm ; then the third zone, with which it is 

 continuous and into which it passes by gradual transition. The third zone contains 

 the distal mass of secretion along the free border of the cell and is remarkable for the 

 extreme delicacy of the cytoplasmic threads which penetrate it. 



The cells of the glands of Brunner of the rat may therefore present one of three 

 conditions according to the phase of activity. Either there is one narrow mass of 

 secretion along the free border ; or there are two distinct masses of secretion, one along 

 the free border and one in the interior of the cell; or, finally, there is a single continuous 

 mass of secretion which shows evidences in the structure of the included cytoplasmic 

 trabeculse of its having been produced by the fusion of two masses originally distinct. 



The cells of the pyloric glands of the rat differ from those of the glands of Brunner 

 in the same way as do the corresponding structures in the muskrat, dormouse, and 

 deer mouse. The cells of the glands of Brunner are from 13.3 ft to 17.2 /*, and those 

 of the pyloric glands from 8.9^ to 10.8 /* in height, although an occasional cell may 

 reach a height of 13 p. The averages are 15.7 ft for the glands of Brunner, and 9/t for 

 the pyloric glands. The differences of size are less obvious when both glands are in 

 the fully loaded condition. 



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