332 
JAMES LAW. 
of the pistil is really an independent fungus. At an advanced 
stage of the development of the sphacelia an adhesive fluid 
exudes from its surface, carrying with it many of the conidia, and 
concretes in the form of oily-looking dark spots. 
Soon the second stage is reached by the development of the 
ergot at the base of the sphacelia and at first invested by it. It 
is compact violet-black outside and white within, and grows rapid¬ 
ly in all directions, extending out of the glumes, carrying on its 
summit the withered remnant of the sphacelia, and sometimes, 
also, some remaining traces of the aborted ovary, including its 
terminal hairs. The fully-developed ergot, or scierotium, which 
projects from the glumes for a greater or less distance, according 
to the natural size of the seeds in the plant attacked, is familiar, 
by its black or violet spur-like aspect, slightly curved, marked 
with longitudinal furrows, and often presenting at intervals 
whitish patches, where the originally investing sphacelia has been 
removed. In one case watched by Tulasne it required a month 
for the ergot to pass through these two stages to its full develop¬ 
ment. In anatomical structure the ergot bears no resemblance to 
the seed, but is essentially the sclerotic mycelium of a fungus. 
Its parenchyma is hard, dry, brittle, and made up at all points of 
minute utricles, with thick walls containing a comparatively trans¬ 
parent oil, very slightly colored by iodine. No starch is usually 
found, though mentioned in the analysis of Legrip given below. 
The third and last stage consists in the development on the 
surface of the ergot of minute bodies like toadstools. On soil in 
which the ergot has been dropped these bodies grow up on stems 
one-quarter to one-half inch in height, with a globular head one- 
twelfth inch in diameter, the whole growing out of the ergot as a 
potato plant grows out of the tuber. The cavities in the globular 
head are filled with sporidia, which, coming in contact with the 
soft ovary of the grass at the earliest stage of its development, 
grows into the sphacelia and ergot. If these sporidia are washed 
into the soil where rye is planted they determine the development 
of ergot in the coming crop, and it is supposed by many that the 
spores are taken up by the rootlets and carried to the flowers in 
the juice of the plant. The fungus developed in the soil from the 
implanted ergot belongs to the genus Spceria. 
