1916] 
DUGGAR—THE TEXAS ROOT ROT FUNGUS GA? 
hyphae are likewise most diverse in diameter, varying from 
those 15-20» to others extremely delicate and flexuous (fig. 
5). No truly acicular branches, however, are produced un- 
der ordinary cultural conditions. With age, the mycelium 
somewhat collapses toward the substratum and has a greater 
tendency to grow along the glass tube in the form of false 
strands. Grown in soil, by covering a vigorous growth on bean 
stems with a layer of loam, hyphae similar to those just des- 
eribed are produced; but, in addition, there are formed here 
and there vesicular enlargements, and the latter are sometimes 
реа" 
9. w deaet omnivorum: hyphae grown on bean stems, from 
a D 60 days 
in clusters, the branches becoming two to three times forked. 
The conditions for conidial formation have not been deter- 
mined. 
It will be seen that the connection of the conidial stage with 
the Ozonium rests at present upon two classes of observation: 
(1) the presence in the conidial layer of hyphae and strands 
(bearing conidia) found to be identical with the character- 
istic mycelium on the roots of affected plants, and (2) the 
identity in artificial culture of the mycelium originating, on 
the one hand, from diseased roots, and, on the other, from 
the germination of the conidia. То complete the proof it 
would, of course, be necessary to secure positive results by 
inoculation with conidia, or better, positive results with a 
pure culture originating from conidia. Unfortunately this 
phase of the work has not been successfully developed. In 
ANGTON UN; 
€ 
=з 
П 
MEn 
ASOC ara QO Se 
-m ` e 
i ech рди”. 
