130 
M. J. Le Goc. 
Fructifications have commenced to develop on several blocks 
(Fig. 7) exposed to light of moderate intensity, but they have not 
proceeded very far; no definite hymenium on basidia have been 
observed, and these rudimentary fructifications consist only of 
compact gelatinous masses of interwoven hyphae. The mycelia 
covering the blocks kept in a dark room have made no attempt to 
produce such fruit bodies, but have grown luxuriantly and spread 
as a white snow-like layer over the whole of the bottom of the 
flasks. 
Fig. 8. Longitudinal section of inoculated Elder twig. Stout and thin 
hyphse passing through the pits. Stout hyphae present in greater numbers in 
short cells. X 600. 
The penetration of hyphae inside the wood used in these 
cultures has been tested at intervals. It is very rapid and after 
three months the hyphae have run all through the tissues. The 
path followed is along the vessels and tracheids with penetration 
through the pits, and more frequent branchings in the medullary 
rays or in the short cells (Fig. 8). In long tracheids we often 
observe only one thread of mycelium, at least in [an early stage. 
For some time the fungus seems to be satisfied with the food found 
inside the cells, but when hunger presses hard on the fungus it 
encroaches on the cell walls, beginning by the pits, which become 
enlarged until the wall between them is consumed (Fig. 9). The 
xylem is delignified, the hyphae bore their way locally through the 
