Benson A. Cohoe 169 
canaliculi, whence they passed into the lumen of the gland tubule. New 
granules were formed within the cell meshwork to replace those thus 
exhausted. These regenerated granules, lying within the meshes, at 
first small, increased in size and gave rise to the stainable granules of 
the dark cell areas. The latter, after attaining a certain size, lost their 
power of taking up stains and were transformed into the unstainable 
granules of the clear cells. In this manner arose the portions of the 
gland tubule containing clear cells. 
Miiller was not the first to observe that the cells of the submaxillary 
of the rabbit were wanting in homogeneity. Nussbaum, 77, in an in- 
vestigation of the process of ferment formation in glands chose this 
gland as the type of a pure serous salivary gland. After treatment 
with osmic acid he found that certain groups of cells assumed a deep 
black stain which distinguished them from other groups of cells within 
the gland. These dark granular cells he believed to be particularly 
rich in ferment. 
Langley, 78, also employed the submaxillary of the rabbit in his studies 
of ferment formation, and gave us valuable data concerning the secretory 
stages of this gland. He treated the gland with osmic acid, as did 
Nussbaum, but was unable to entirely confirm the results obtained by 
the latter observer. Nussbaum represented the intercalated ducts or 
ductules as composed of small, elongated cells, from which without 
intermediate forms there is a sudden change into the large cells of the 
alveolus. In this view he was supported by von Ebner, 72. Langley 
found that, while it was true that certain cells forming the part of the 
alveolus immediately succeeding the ductule were more deeply stained 
than those of the more peripheral part of the alvolus, yet there was no 
section in which any marked difference in coloration between the cells 
lying next to the ductules and the cells of the ductules proper could 
be discerned. In all of his sections the intralobular ducts were stained 
most deeply, the ductules and neighboring cells less deeply, and the 
distal alveolar cells least of all. His conclusion was: “It appears to 
me, on the contrary, that the cells composing the ductule are but slightly 
elongated or not at all, and graduate as to size and appearance into the 
alveolar cells, so that of particular ones it is difficult to say whether 
they belong to a ductule or an alveolus, hence I name them transitional 
cells.” ; 
Held, gg, in a series of researches upon granules and gland protoplasm 
studied the granule forms in the submaxillary of the rabbit. He dis- 
tinguished three forms of cells characterized by three kinds of granules. 
