560 A. B. DAWSON 
ther than this Nirenstein was unable to trace the process, but 
four months after the discharge of the glands no trace of the 
empty sacs could be found. Further, he found that other - 
glands, discharged at the same time, did not show any degenera- 
tive changes and ‘‘das ganze Aussehen der Driise spricht fir 
die Lebens- und Entwicklungsfihigkeit des Organs” (p. 105). 
In Bufo agua, according to Bristol and Bartelmez (08), 
“When the poison is discharged, the remains of the glands are 
resorbed, and at the same time one of the five or six undeveloped 
glands, grouped about the mouth of the functioning gland, 
grows down alongside the remains of the discharged gland 
pushing it aside to occupy its former place.’ Shipley and 
Wislocki (15), who worked on the same animal, confirm the 
statements. 
b. In Necturus. In Necturus the granular cells are trans- 
formed bodily into the secretion and the cell walls disintegrate, 
converting the gland sac into a reservoir for secretion. During 
the expulsion of the secretion the nuclei of the secreting cells are 
pulled away from the muscular layer and many are forced through 
the duct to the exterior (fig. 20). In most cases the whole appear- 
ance of the emptied glands would lead to the conclusion that 
their time of functional activity is at an end. However, in a 
few cases I found discharged granular glands that showed unmis- 
takable signs of a renewal of secretory activities. Within them 
were small masses of newly elaborated secretion, easily identified 
by its appearance when fixed, but there was no evidence to 
indicate the source of the secretion. It may have been pro- 
duced by some cells which had not been completely converted 
into secretion at the time the gland was emptied or, as some 
authors have suggested, it may have been the direct product of 
the naked nuclei, although there was absolutely no evidence 
that the nuclei were secreting. 
In many glands, on the other hand, no signs of renewed activity 
by the remnants of the old epithelium were observed, and the 
nuclei of the old secreting cells were in a state of disintegration. 
Furthermore, many leucocytes of both the mononuclear and 
polymorphonuclear types, as well as pigmented wandering cells, 
