198 Dr. W. H. Woglom. Nature of the Immune [Mar. 15, 



and is indicated toward the lower edge of the illustration to the right of the 

 centre. The hyaline remains of the old stroma, its penetration by poly- 

 morphonuclear leucocytes, and the serious involvement of its connective tissue 

 cells are also reproduced, as well as the active mitosis that is in progress 

 among the elements of the parenchyma at the growing edge of the graft ; but 

 the necrotic tumour cells in the centre of the fragment are not included in 

 the picture. The surviving cells of the parenchyma, which have hitherto 

 been content merely to sustain life and to proliferate as best they may, now 

 often show signs of an attempt to assume an acinous arrangement. 



in parenchymal cells, old stroma degenerated. Borrel, iron alum hematoxylin, x 410. 



Whether the new framework is derived entirely from the connective tissue 

 of the host, or whether certain cells of the transplanted stroma survive long 

 enough to participate in its construction, is a question difficult of decision. 

 Certain it is that all of the elements of the transferred stroma seem to be 

 considerably damaged before the entrance of connective tissue corpuscles 

 from the host ; still the possibility cannot be eliminated that the damaged 



