ANATOMY OF THE ALIMENTAEY CANAL. 
473 
The bud-like groups are sometimes found of considerable size, and, when this is the 
case, they call to mind the foldings of the epithelium, which have been described in the 
intestine by Donders (12) and Kolliker, and figured by Todd and Bowman*; they 
have also been figured by Ebstein f in the stomach. These buds are found, however, 
not only on the sides of the villus-like processes of the stomach, but also on the flattened 
surfaces of those processes ; and they are seen among the epithelium covering the sides 
of the villi of the intestine, or on the sides of the plicae villosae, where there is no apparent 
folding of the epithelium. If, however, the short plicae villosae (in the depressions 
between the wave-like elevations of the stomach) be examined (see fig. 26, Plate 42), the 
epithelium is seen to be in folds, giving the appearance of large buds. Whether we have 
here one of the plicae villosae, temporarily shortened by the contraction of its muscles, 
with a consequent folding of the epithelium, or whether we have some more permanent 
process associated with repair, I have no evidence on which to decide. 
These bud-like structures are found in great numbers in young animals, and at first 
it seemed possible that these buds were the means whereby the epithelium increases in 
growing animals ; and possibly it may be so, as Bemak (100) has observed in the intes- 
tine the increase of epithelium by longitudinal division. These buds may, however, be 
seen in the epithelium of animals which have attained their full maturity, as was proved 
by sections made from the stomachs of five dogs, of the ages of two years and upwards. 
I consider, therefore, that these bud-like structures are concerned in the repair of the 
epithelium, and that this repair is constantly needed during the life of the animal. 
The foregoing results were obtained from a great number of observations, and were 
chiefly made from sections of the stomach of the dog. I have, however, one prepa- 
ration from the pyloric end of the frog’s stomach (Plate 42. fig. 34), which may possibly be 
explained by the view that Donders (12) and Kolliker (93) took of the regeneration 
of the epithelial cells — i. e. “ that the cylindrical cells of the intestine not unfrequently 
burst at their apices, and allow a part of their contents (mucus) and their nucleus to 
pass out ; a second, previously formed cell-nucleus then serves for the regeneration of 
these cells ; . . . . these are the cells designated by Gruby and Delafond ‘ epithelium 
capitatum,’ i. e. goblet-cells.” 
The Connective-tissue JReticulum among the Columnar Epithelium. 
This reticulum is, in its character, exactly like that which has been already described 
among the epithelium of the intestine, and can be best seen, among the epithelium of the 
ducts (see fig. 35, Plate 43). It is much harder to demonstrate its occurrence among the 
epithelium of the surface of the plicae villosae ; and though it does exist even among that 
epithelium, it is very fine and delicate, and does not appear to reach the surface. There 
is, however, an intercellular substance uniting the upper surfaces of the epithelial cells, 
which diflers very materially from the connective-tissue reticulum, in the fact that it 
does not stain at all in haematoxylin. 
* Loc . cit . fig. 159. 
3 U 
MDCCCLXXVI. 
t Loc . cit . fig. iii. 
