SYNGENESIOTRANSPLANTATION 77 



tended to survive even under homoiogenous conditions of transplantation, but 

 were unfavorably affected by a marked disharmony of the homoiogenous 

 individuality differentials. 



(4) The uterus is, on the whole, also a resistant organ, although certain of 

 its constituents may show less resistance. There was often necrotic material in 

 the lumen of the uterus and part of its wall could be destroyed. The epithelium 

 and the peritoneal endothelium were more resistant, while the unstriated 

 muscle tissue was more readily injured after homoiogenous transplantation, 

 and cellular, myxoid and predecidual connective tissue underneath the epithe- 

 lial structures continued to live only if the individuality differentials of host 

 and transplant manifested a high degree of compatibility. 



(5) In kidney transplants the tubules and glomeruli, situated in the peri- 

 phery of the transplant, were most prone to survive; the collecting tubules, 

 with pelvis and ureter showing the least differentiation, were very resistant. 

 On the other hand, the convoluted tubules were very sensitive to the injurious 

 action of the unfavorable individuality differentials. 



(6) After transplantation of pieces of liver, peripheral bile ducts remained 

 alive in about fifty per cent of our transplants for 1 or 1^ months; they 

 showed mitoses mainly in the earlier periods, as, for instance, 14 days after 

 transplantation, but some mitoses were visible at later periods. The bile ducts 

 corresponded, therefore, in their power ,of resistance to unfavorable indi- 

 viduality differentials, to the small follicles of the ovary or to spleen tissue. 

 New bile ducts could develop and these structures were able to survive for as 

 long as a month and a half, even under homoiogenous conditions, although 

 they were better preserved after syngenesiotransplantation. In 38 per cent of 

 the transplants in which bile ducts were preserved, or in a little more than 

 on-sixth of all our transplantations of liver, liver cells as well survived, which 

 is about the frequency with which megakaryocytes were preserved in the 

 spleen. However, liver cells did not survive if the individuality differentials of 

 the transplant were homoiogenous; but they could survive in favorable syn- 

 genesiotransplants, under conditions in which also mitoses were seen in the 

 bile ducts. In certain instances, a liver cell with two nuclei was noted, but only 

 in one case was a mitosis seen in such a cell. It may be remarked in this con- 

 nection that under exceptional conditions mitoses may appear in young carti- 

 lage cells, or even in transplanted cells of striated muscle tissue. As in ovary 

 and kidney transplants, so too in liver transplants the necrotic center could 

 remain partly unorganized for a long time. 



(7) Spleen: Between 36 and 47 days following transplantation spleen tissue 

 was found preserved about as frequently as bile ducts in liver transplants or 

 small follicles in ovarian grafts. Here, again, homoiotoxins proved injurious 

 and the injury increased with increasing time following transplantation; 

 eventually, only fibrous tissue with blood pigment was found. Syngenesio- 

 transplants were more favorable and in these as well as in autogenous grafts 

 Malphigian bodies, blood sinuses containing erythrocytes, mononuclear, pha- 

 gocytic cells and trabeculae were seen, and at later stages megakaryocytes. 



(8) Testicle: Testicle tubules as a rule perished, but a few peripheral ones, 



