TRANSPLANTATION OF THE VENOM GLAND. 41 



SERIES II. 



In this series a portion of the poison gland of one individual was excised 

 and transplanted to the left side of the thorax of a different individual. 



EXPERIMENT A. GLAND REMOVED ONE WEEK AFTER TRANSPLANTATION. 



On June 4 a part of the right poison gland of individual K was trans- 

 planted to the left thoracic wall of H. On June 11 this was removed and 

 fixed in Kopsch fluid. A portion of this gland is shown in fig. 14. In its 

 general features sections of this gland resembled those of H 1 , as described under 

 Series I. The chief difference was in the size of the intermediate pycnotic 

 zone, w r hich was either very narrow or absent in this gland. The periphery 

 of the gland consisted largely of a relatively broad zone of apparently normal 

 gland-tissue, aggregated into tubules and acini, all of which were provided with 

 clear and distinct lumina. 



The inner necrotic portion formed fully three-fourths of the entire mass 

 of the transplanted piece. Here the various lobules and their subdivisions 

 were distinctly visible, and even the lumina of the tubules were recognizable, 

 but the cellular elements were fully necrotic. No typical secretion granules 

 were observed in any of the cells of this gland. 



EXPERIMENT B. GLAND REMOVED Two WEEKS AFTER TRANSPLANTATION. 



This piece of gland was obtained from individual H on June 4 and was 

 transplanted to K, from which it was removed on June 18. This piece, 

 designated K 2 , was nearly normal throughout. Only in the very center of the 

 section was a relatively small necrotic area. The cells of the approximately 

 normal portion had the usual size, but their cytoplasm appeared rather more 

 granular than normal. The typical secretion granules were also present, but 

 were confined to the intralobular ducts of a few lobules. In this specimen the 

 nuclei, even of otherwise apparently normal cells, appeared to be much shrunken. 



As mentioned above, the necrotic area was confined to the central part 

 of the transplanted piece. In places the pycnotic and necrotic elements were 

 inclosed by an investing sheath of fibrous tissue. Usually the tubules of these 

 areas were distinct, but in most cases they lacked a distinct epithelial lining 

 and their lumina were greatly occluded by large quantities of desquamated 

 cells and necrotic matter. 



In all tubules, both normal and pycnotic, there were large accumulations 

 of desquamated cells. 



EXPERIMENT C. GLAND REMOVED THREE WEEKS AFTER TRANSPLANTATION. 



This piece of gland, M 2 , was obtained from individual N on May 31 and 

 transplanted to M, where it was allowed to remain until June 21, when it was 

 removed and fixed in Kopsch fluid; part of it was transplanted to a mouse 

 just after the second removal, the mouse dying within a few days. M 2 was 

 rather less normal than piece K 2 , removed two weeks after transplantation, 

 and in many respects closely resembled the piece H 2 , removed after one week. 

 Most of the peripheral portion, forming about one-third of the total mass, 



