VIl] 



PERONOSPORITES. 



219 



tissue one sees under a moderately high power that the cells 

 have become partially separated from one another by the 



Fia. 44. Cells with fungal hyphae. A. A piece of disorganised tissue, 

 showing the separation of the cells. B. Part of A more highly magnified. 

 C. A single cell containing two swollen hyphae. D. Partially destroyed 

 cell-membranes pierced by fungal hyphae. (Drawn from sections in the 

 Edinburgh Botanical Museum, originally described by Cash and Hick.) 



destruction of the middle lamella (fig. 44 A). The cell- 

 cavities and the spaces between the isolated cells contain 

 numerous fine fungal hyphae, which here and there terminate 

 in spherical swellings. One such swelling is shown under a low 

 power in fig. 44 A, in the middle uppermost cell, and more 

 highly magnified in fig. 44 B. In fig. C there are two such 

 swellings (the larger one having a diameter of '003 mm.) in 

 contact, but the connection does not appear to be organic. 

 The cell-walls of the infected tissue present a ragged and 

 untidy appearance, and in places (e.g. fig. 44 D) the membrane 

 has been pierced by some of the mycelial branches. 



This fungus bears a close resemblance to Peronosporites 

 antiquarius, but it is impossible to determine its precise 

 botanical position without further data. In Cash and Hick's 

 paper in which the above fungus is briefly dealt with, some 



