216 Gastric Glands of Dog after Gastroenterostomy 
obtain satisfactory results with mucous staining dyes in any of these 
cells. 'Toluidine blue failed completely to demonstrate the presence of 
prozymogen or zymogen granules. 
Notwithstanding the failure of these cells to take any stain with 
mucous staining dyes, he considers the glands so modified to be muci- 
parous in function and similar to normal pyloric glands, basing his 
conclusion upon their general appearance with large lumina and sinuous 
outlines, upon their connection with large foveole, upon similarities of 
structure of their cells, and upon the absence from them of zymogen 
or prozymogen. He finds such modifications only in the immediate 
vicinity of the anastomosis. At some distance from it the mucous 
membrane is unaltered and preserves all the characters of normal fundus 
mucosa. Between this normal mucosa and the line of operation is a 
transition zone in which as the area examined is progressively farther 
from the new pylorus, the following changes were observed: ‘The lumina 
become successively narrower and more regular; parietal cells appear, 
at first pale and poor in granules, gradually becoming more granular and 
richer in nuclear chromatin. Ferment cells appear in the ends of the 
glands with zymogen staining in toluidine blue and prozymogen staining 
in Bismarck brown, constituting a steadily increasing proportion of the 
chief cells of the gland body until the structure normally present in the 
fundus region is attained. 
His observations may be summarized in the statement that at the 
site of a gastroenterostomy made in the fundus region, there is formed 
a new pylorus which is similar to the normal pylorus in the general form 
of the glands present, in their relation to the foveolz and in the character 
of the glandular elements. Upon this observation he bases the con- 
clusion that these structures possess a morphological flexibility and an 
ability to transform themselves in response to the influence of new and 
altered conditions of existence and to assume the performance of new 
functions quite different from those which they usually perform. 
DISCUSSION OF CADE’S WorK. 
These observations and conclusions have bearings upon several im- 
portant theories, first, that of the specificity of cells. They indicate 
that for these cells, at any rate, specificity in the sense in which Bard, 98, 
uses the term, does not exist. The second is that of the cause of differ- 
entiation of the pyloric mucous membrane. If it can be produced at 
will by the surgeon from fundus mucosa by subjecting it to the influence 
of mechanical conditions which he can at any time induce, a strong 
