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384 REPORT OF THE COMMISSIONER OF “AGRICULTURE. 
mination took place in water very readily. He holds this to be the _ 
general rule. In April one-half the spores used in the experiment 
germinated in water in two days. According to his observations — 
spores will retain their vitality for as long as two years, At that 
age they will not germinate in water, but will germinate in a nutri- 
tivesolution. Thistakes place less readily than when they are about 
six months old, but having germinated they grow with as great ac- 
tivity as fresher spores. 
Manner of gernination.—W hen the spores germinate in water or — 
a moist atmosphere the process is as follows: The inner coat and con- 
tents swell, burst the outer coat, and protrude asa tube (Plate XIV, _ 
Fig. 12, a—d) called the promycelium, into which the protoplasm passes. : 
Several cross partitions are formed, dividing the filament into several 
cells. At these and at the tip spore-like bodies, conidia or sporidia, 
are formed (Plate XV, Fig. 1). In many species of smuts the spo- 
ridia unite or conjugate in pairs; their contents coalesce and from the 
resulting body a filament grows which may enter the tissues of the 
proper host plant. The Corn Smut, however, is especially character- 
ized by the absence of this process. The sporidia germinate singly 
and produce mycelial threads (Plate XV, Fig. 4, a), which may pene- 
trate the tissues of the corn plant. 
This is the normal mode of germination, but another mode, dis- 
covered by Brefeld, is of great scientific interest and practical impor- 
tance, and to neglect to consider it in practice may render all remedial 
efforts useless. 
When the spores were sown in a nutritive solution the conidia did 
not germinate by tubes, as described above, but by budding like yeast _ 
(Plate XV, Figs. 3and4). The cellssoon become detached from the 
spore, and the growth continues in this manner, each conidium pro- 
ducing, by budding, bodies like itself, which become detached and in 
turnform buds as before, and the entire growth is of this kind (Plate 
XV, Fig. 4). 
But if the nutriment becomes exhausted, these yeast-like cells form 
mycelial filaments which bear conidia as when the spores germinate — 
in water (Plate XV, Figs. 5 and 6). Brefeld’s experiments were fre- 
quently made in a drop of the nutritive fluid, in order to keep them 
within bounds for microscopic examination. In some cases the ex- 
periment was varied by adding another drop when the nourishment 
in the one wasexhausted, and when this was done the budding growth 
was renewed and continued as before. It was found that this mode 
of growth would go on indefinitely if nourishment was within reach . 
of the fungus. This same thing has been found to take place in na- 
ture, in the dung of animals that have eaten smutty corn, and the 
same may be expected to take place when any smutty corn finds its 
way into manure piles. Thus its vitality may be preserved indefi- 
nitely, and it is ready to form mycelial tubes and enter the corn when 
the latter is planted in ground fertilized with such manure. 
This form of the fungus being in active growth is perhaps in better 
condition to seize upon the young corn than the spores are, especially 
after the first spring. 
Manner of entering the host.—For along time all efforts to discover 
how the fungus gained entrance into its host were unsuccessful, ex- 
ae in the cage of the bunt of wheat observed by Kiihn. The my- 
celium was found in very young corn plants and hence was believed 
to gain entrance at some part of the plant near the surface of the 
ground. Wolff finally observed the penetration of several species of 
