PHYSIOLOGY OP PEPSIN-FORMING GLANDS. 
693 
become smaller and fewer, the cell-substance begins to stain, the cells are smaller, and 
the lumen often visible (see Plate 78, figs. 9, 10). These changes are most pronounced 
in the latter third of the oxyntic gland region. The lumen is never large ; it may be 
either straight or zig-zag, depending on the position of the cells in the gland tube. It 
is to be remarked that osmic acid brings out a number of granules in cells which in 
the fresh condition showed scarcely any. In this respect osmic acid specimens show a 
less striking difference between the anterior and posterior oxyntic glands than is shown 
by the fresh specimens. 
I have not noticed any great change from normal in the glands of the fasting Snake. 
The cells become somewhat smaller; this is marked in the posterior gastric gland 
region by an increase of the lumen ; the cell-substance, too, especially in the posterior 
gastric region, stains more deeply with osmic acid, and contains smaller granules. 
In the posterior oxyntic region during digestion the granules disappear somewhat 
more at their inner than at their outer portion (see Plate 78, fig. 9) ; this is, however, 
so far as I have observed, much less markedly the case than in the Frog. 
The Pepsin-content of teie successive Eegtons of the Stomach of the Snake. 
Having observed that in the digesting stomach the diminution in the number of 
the granules became more and more marked in passing from the anterior to the 
posterior region, I made some experiments to determine whether there was a corre¬ 
sponding diminution in the amount of pepsin. I divided the mucous membrane 
containing gastric glands into four parts, throwing away a strip between each part. 
The four pieces were then put aside to dry in a bell-jar containing sulphuric acid. A 
definite weight of the dried mucous membrane of each part was taken and treated 
with dilute hydrochloric acid for twenty-four hours. The details of the method of 
proceeding were in the main like those given above (p. 681) in the account of the 
pepsin-content of the stomach of the Frog. 
The first experiment was on a Snake that had been fed with a Frog twenty-four 
hours previously. Only that part of the Frog which was in the posterior portion oi 
the stomach had been much digested. The glands of the posterior portion of the 
stomach were distinctly granular, although they were, as a rule, rather more thinly 
granular at their outer portion. The analysis showed a steady diminution in the 
amount of ferment from the beginning to the end of the stomach, the first part con¬ 
taining more than the second, the second than the third, the third than the fourth. 
The fourth part contained very much more than an equal weight of the mucous 
membrane of the pyloric region. 
The second experiment was made on a Snake sixty hours after feeding with a Frog. 
The legs of the Frog, which were in the anterior part of the stomach, were still nearly 
intact. Examined in the fresh state, the first part of the stomach showed many 
granules ; the second part showed less than the first, but still a considerable number; 
the third part few granules ; the last part very few. 
