36 THE VENOM OF HELODERMA. 



other cases it formed discrete particles or knots, the remainder of the nucleus 

 being nearly clear. None of the cells on this gland were observed to contain 

 typical secretion granules. 



Experiment B. Gland Examined Two Weeks after Transplantation. 



On the same day that animal H was operated upon, another individual, 

 K, was also operated upon. Its right gland was exposed and a portion removed. 

 This was then divided into two pieces, one piece, K 1 , being transplanted to the 

 right thorax, while the other, H 2 , was transplanted to the left thorax of H. 



Two weeks later, June 18, the former piece, K 1 , was removed and cut into 

 two pieces. The larger piece was fixed in Kopsch fluid, the smaller trans- 

 planted to an albino mouse, which died shortly afterwards. In this gland the 

 same zones were observed as in the preceding, i. e., a superficial zone of nearly 

 normal gland-tissue, a middle zone of pycnotic elements, and a central area 

 of necrotic material. 



The area occupied by the apparently normal gland-tissue was considerably 

 larger in this than in the preceding, H 1 , and it had a much more healthy aspect. 

 In H 1 this area formed a very thin zone, while in K 1 it formed nearly a third of 

 the entire transplanted piece. In some of the tubules and acini a large and 

 distinct lumen was present, quite normal in every respect, and in some of the 

 cells of the tubules the typical secretion granules were observed, whereas in 

 the transplanted piece, removed one week after transplantation, no trace of 

 these was evident. In many of the tubules and acini the lumen was more or 

 less occluded by dead and desquamating cells in a manner similar to that 

 found in H 1 . The nuclei of these cells in the peripheral tubules were appar- 

 ently quite normal, in strong contrast to those of H 1 , which were nearly all 

 shrunken. Some of the nuclei of the gland K 1 presented the same shrunken 

 aspect, but they were the exception and not the rule. 



The middle pycnotic zone was variable. Those cells lying nearest the 

 normal layer were rather indefinitely outlined, but had nuclei of nearly normal 

 form and size, with a clear ground-substance and somewhat scattered chromatin 

 particles. The deeper cells were more degenerated, with small shrunken nuclei 

 in which the chromatin was massed in lumps. 



The necrotic portions had no special features to warrant description. It 

 was similar in every respect to the corresponding portion in H 1 . 



Experiment C. Gland Removed Three Weeks after Transplantation. 



An animal (M) was operated upon on May 31. As in the other cases the 

 right gland was exposed and a portion of it removed. One half, M 1 , of this 

 was then transplanted to the right thorax, while the other half, N 2 , was trans- 

 planted to the left thorax of another individual, N. Three weeks later the 

 transplanted gland M 1 was removed. Part was fixed in Kopsch fluid and the 

 remainder transplanted to a mouse, which died within an hour after the 

 operation. 



As shown in typical sections, this gland appeared to consist of equal parts 

 of normal and necrotic elements. Toward one side all the lobules were normal ; 



