8 HUMPHREY 
showed evidences of comparatively few hyphez which evidently 
served to connect the more functionally active interior system 
with those in the rhizoids and with the substratum. Thus far 
the habit of growth of this fungus agrees quite consistently with 
those described by Cavers. 
At about this period in its development one may observe, scat- 
tered here and there throughout the infected zone, vesicles of 
considerable size and presenting a variety of form. ‘These ap- 
pear as great enlargements of the hyphe and are full of rather 
coarsely granular protoplasm (Fig. 6). This protoplasm has 
within it minute nuclei, at first rather few in number but as the 
vesicles become older and larger increasing in number until 
they quite fill the interior of the vesicle. It was further found 
that in some instances at least these vesicles are connected with 
the exterior by hyphe (Fig. 8) and along the course of these 
hyphz may be seen certain of these nuclear bodies. Whether 
or not they make their escape to the exterior as zodspores could 
not be demonstrated, but their development and subsequent be- 
havior is suggestive. In his recent work upon the development of 
Ophioglossum pendulum and other members of the genus, 
Campbell” has demonstrated the presence of thin-walled vesi- 
cles in the endophyte. In these the behavior of the nuclei 
resembles that occurring in the vesicles of the endophytic fun- 
gus found in the Fossombronza. In Fossombronia these vesicles 
completely fill the host cells in which they occur, in some cases 
causing a considerable distention of the cell. 
As stated above, the amount of chlorophyll or of starch and 
other products of metabolism varies with the degree of infection. 
Certain cells of the host seem packed with hyphe, and a micro- 
chemical test fails to reveal any of the products of the normal 
cell, and while a large part of the stem appears to be dying, 
the leaves and the uninfected stem tissue seem to be vigorous 
and unaffected by the presence of the fungus. Comparison of 
infected plants with those entirely or nearly free from fungus in- 
vasion seems to demonstrate that up to the vesicle stage of devel- 
opment the growth of the host is not abnormally stimulated, in 
tC; Cit., p.32—33. 
2 Campbell, 1907. 
far daneres Moreen ek Meee ferry ae Yew ments en ae 
