1916] 
GILMAN—CABBAGE YELLOWS 27 
plants from badly diseased fields. In his last paper he re- 
ported that in the resistant strain 100 per cent formed com- 
mercial heads, or a yield of 18.8 tons to the acre; on the other 
hand, in the commercial strain used as controls, only 46 per 
cent of the plants lived and 24.2 per cent headed, or a yield 
of 2 tons to the acre. 
These results show that, as far as practice is concerned, 
the disease has been controlled, but much remains to be done 
on the other aspects of the problem of the relation of host and 
parasite. Before discussing these phases, however, a brief 
description of the disease will not be out of place. 
SYMPTOMS OF THE DISEASE 
The first evidence of the disease in the greenhouse is found 
on very young seedlings, often just after the appearance of 
the first true leaf, and is characterized by a rapid wilting of 
the cotyledons and dying of the roots while the stem is still 
turgid and, to all external appearances, normal. If, however, 
the conditions are not favorable for the attack of the fungus 
so early in the life of the host, the characteristic symptom 
—the yellowing of the leaf, to which the disease owes the name 
of ‘‘yellows’’—is found. This yellowing may invade the en- 
tire plant, in which case wilting and death rapidly follow, or 
it may be confined to merely one side of the plant or leaf. 
If this one-sided invasion occurs, the plant or leaf ceases 
growth on the diseased side, but the green portions continue 
their development, bringing about a curvature of the plant 
or leaf toward the diseased area. This type is most fre- 
quently found on plants grown in the seed-beds in infected soil. 
These one-sided plants are usually stunted with the leaves 
loosely attached to the stem, so that they fall at the touch. 
If transplanted into the field such plants may die immediately, 
or if conditions are favorable for their development, they 
may live all summer, becoming stunted individuals with the 
lower leaves dying and dropping off, leaving a tuft of living 
leaves at the tip of a bare stalk. When healthy seedlings are 
transplanted to diseased soil the same characteristics occur ; 
some plants die immediately—first, however, losing their chlo- 
