182 BOTANICAL GAZETTE [SEPTEMBER 
of thorough study by Appet and his co-workers (2,4). Eventually 
the plants infected with F. trichothecioides showed much severer 
symptoms than those inoculated with F. oxysporum (fig. 6). Eight 
plants died in the former sets, and 3 in the latter. Plants infected 
with F. trichothecioides showed such severe and rapid burning and 
Fic. 4.—Leaf roll and rosette of field plant of the Pearl variety; August 1912, 
at the U. S. Substation at Mitchell, Neb. 
drying up of leaves, that the typical wilting phenomena were 
scarcely realized. The vascular bundles were blackened and the 
blackening extended even into the petiole and the leaf veins. This 
rapid killing was at first strictly localized on that side of the plant 
to which the inoculum had been applied, even in the leaf, where the 
leaflets on one side of the midrib would be affected, and those on the 
other side not. Eventually in those cases in which killing of the 
