PHYSIOLOGY OF PEPSIN-FORMING GLANDS. 
689 
too, that the time during which it can take place is shorter even than in the Frog, for 
in the Newt a distinct decrease is generally obvious in half an hour to an hour. More¬ 
over, in some cases of fasting Newts, i.e., Newts with gastric glands diminished in size 
and containing granules diminished in number, I have observed a distinct diminution 
in a quarter of an hour which steadily progressed up to six hours. 
The effect of sponge feeding on the oxyntic glands is much more marked in the Newt 
than in the From There are wide variations in the extent and duration of the changes 
depending on the condition of the animal. But apart from this, the character of the 
change produced tends towards one of two types : the first, a diminution in the size 
of the cells and in the number and size of the granules without a very distinct forma¬ 
tion of inner and outer zones ; in the second, a distinct formation of zones without any 
very great diminution in the size of cells and with only a moderate diminution in the 
size of the granules. It will be observed that these types correspond respectively to 
(l) the type of change in normal rapid digestion; (2) the type of change with abnormal 
slow digestion. That which chiefly affects the character of the changes in the glands 
is, so far as I have observed, the amount of sponge given,* i.e., the strength of the 
stimulus. In both cases the changes proceed very slowly, the first effect being obvious 
in about four hours, and steadily progress for one to two days; about this time 
the glands begin slowly to recover. Sometimes after feeding a Newt with a relatively 
large quantity of sponge the glands lose all or nearly all their granules and approximate 
in appearance to fig. 5, Plate 78. This is especially the case if the Newt has fasted 
for some time previously. When the sponge is removed the glands recover, although 
not very rapidly, their normal appearance. Glands in which the first type of change 
has occurred form small granules which soon stretch throughout the cells; the cells 
and their granules then together become larger. Plate 78, fig. 7, shows the 
first stage of this return ; the granules are small, and though absent from the outer 
part of the cell do not form a dense zone around the lumen. (Dark clumps of fat 
globules are seen at the periphery, cp. p. 670.) Glands in which the second type of 
change has occurred continue to show distinct zones for some hours after the granules 
have begun to increase. Plate 78, fig. 6, shows the condition of the anterior oxyntic 
glands in a Newt which had been fed for eighteen hours with sponge, and the stomach 
of which was put in osmic acid six hours after the removal of the sponge. 
The Pepsin-content oe the Gastpjc Glands. 
In the same manner as that given above for the stomach of the Frog I have analysed 
the amount of pepsin contained by the anterior oxyntic, the posterior oxyntic, and the 
pyloric glands in Triton tceniatus. 
The amount of pepsin contained by the pyloric glands is very small; in both oxyntic 
* I may mention Chat the most marked instances of the second type of change I obtained in February, 
1880; of the first type of change in the autumn of 1880. 
MDCCCLXXXI. 4 U 
