394 Howard . — On some Diseases of the 
Fig. 8 the dwarfed roots from a similar portion of an affected 
cane are shown on a larger scale. On splitting open the lower 
portions of the stem, the vascular bundles are often reddish, 
while towards reaping-time cavities occur in the internodes, 
in which, when the canes are nearly dead, white mycelium 
can be detected with the naked eye. The still living leaf- 
sheaths are covered with a layer of white matted mycelium, 
and reddish spots are common thereon. Black elliptical areas, 
surrounded by a reddish border, are also abundant on the 
leaf-sheaths, which are in some cases slimy to the feel on the 
inside after rain, when hard, yellowish, spherical bodies, about 
the size of a small pea, attached to the outside of the leaf- 
sheaths by whitish threads, are to be seen. Colonies of small, 
yellowish-white toadstools are to be met with after heavy 
rains on the lower parts of the diseased shoots (Fig. 9). 
These persist only for a day under the most favourable 
circumstances, and for this reason appear to have escaped 
attention hitherto. Specimens for examination, or for the 
production of spores, are best collected as soon after day- 
break as possible, as the sun dries them up very rapidly. 
All these characters are to be made out on canes affected 
by this disease. The matted white mycelium on the dead 
leaf-sheaths, the reddish areas on those still alive, and the 
aborted and undeveloped roots are constant characters, while 
the black elliptical areas, although common, are not always # 
present. The yellow spherical bodies and the slimy leaf-sheaths 
are comparatively rare. 
The white fungoid growth which cements the old leaf- 
sheaths to the stem proved to be a branched, septate mycelium, 
very variable in diameter, which exhibited the clamp-con- 
nexions chiefly met with among the Basidiomycetes. 
A similar mycelium was found around the aborted roots, 
in fact, these were often imbedded in a thick felted mass 
of hyphae. It was further detected in great quantity between 
the still living leaf-sheaths and in the cells of the reddish 
areas noted on these, and also in the tissues of the aborted 
roots themselves. 
