364 ADOLPH R. RINGOEN 
es erreichen nicht alle Zellen die freie Oberfliche, son- 
dern viele bilden eine untere Schicht und entbehren des Pfropfes. 
Diese lassen die Magendriisenzellen aus sich hervorgehen. Sie wandern 
aus, ein kurzer, halbkugeliger Fortsatz ragt aus dem Epithel heraus, 
vergrossert sich, der Kern riickt nach. Andere dicht daneben lie- 
gende tun dasselbe, so dass eine Knospe an der Epithelbasis zum 
Vorschein kommt. Die Zellen bleiben mit einem lang ausgezogenen 
Ende zunichst noch mit dem iibrigen Epithel in Verbindung. Immer 
mehr Zellen riicken nach und drangen die erst ausgewanderten 
weiter : 
Since I have ‘already discussed the origin of gland rudiments 
in Squalus acanthias specimens, no further attempt will be made 
here to consider them in detail. Suffice it to say that in speci- 
mens 133mm. long, gland rudiments differentiate in the gas- 
tric epithelium itself—not from special embryonic cells set apart 
with the early differentiation of the entoderm (as Miss Ross 
(02) maintains for Desmognathus, Amblystoma, and pig), 
—but from typical epithelial cells (fig. 2). 
It may be remarked that Peterson’s observation that in 
Acanthias vulgaris embryos of 55 to 70mm. in length not all 
of the epithelial cells reach to the free surface—lumen side of 
the stomach—‘‘sondern viele bilden eine untere Schicht und 
entbehren des Pfropfes. Diese lassen die Magendriisenzellen 
aus sich hervorgehen . . . ,” is not in accordance with 
what I find in the epithelium of Squalus acanthias. For it 
is clearly seen in embryos of less than 133 mm. in length that 
all of the epithelial cells at this stage present the closest morpho- 
logical features and staining reactions. They are all of equal 
length, and, therefore, they all reach to the surface.2 Even 
° In support of my results I wish to quote from Kirk’s (’10) paper with par- 
ticular reference to Toldt’s (’81) work on the rudiments of glands in the fundic 
portion of the cat’s stomach as large, eosinophilic cells interpolated at the base 
of the surface epithelial cells. ‘“Toldt is sure these cells are of epithelial origin, 
but believes they at no time reach the surface, being always shut off from the 
latter by the overhanging distal ends of the tall pyramidal surface epithelium; 
he suspects that they arise from young Ersatzzellen. His Ersatzzellen have 
almost certainly been shown by the work of Stéhr (1882) and Bizzozero (1888) 
to be ‘Wanderzellen.’ Griffini and Vassale maintain that Toldt’s figures and 
text harmonize remarkably with their findings, except that Toldt, through use 
of oblique sections, erroneously concluded that these primary gland cells do not 
reach the surface, and that their lumen is thus not at first continuous with the 
