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58 MISSOURI BOTANICAL GARDEN. 
ducing infection. The sclerotia are not as long-lived as 
generally supposed, for, under suitable conditions, they ger- 
minate soon after maturity, which power decreases directly 
with the age of the sclerotia. When kept in moist soil for 
three months a large number disintegrate, leaving the hard, 
black exterior. But few sclerotia live more than a year. The 
pseudo-sclerotia produce conidia after a short period of rest; 
those that do not germinate rot in a few weeks, none surviving 
to the next season. 
Germination of the sclerotia: From sclerotia developed on 
the lettuce and pepper plants a large number of cultures were 
started early in December, so that by January almost two 
thousand sclerotia were available. Those obtained from the — 
peppers in the fall were kept in a dry place for three months. 
At this time two hundred cultures which had been gradually 
accommodated to the lower temperature were placed out of 
doors. The “drop” in the greenhouse being at its height, a 
large number of sclerotia were obtained from this source also. 
Some of them were left on the soil for further observations. 
The first series of experiments was started January 15. 
Sclerotia from the above sources were placed in flasks con- 
taining sterilized sand moistened with sterile water. A 
similar experiment was set up every two weeks until May 15, 
a period of four months. Beginning March 1, there were 
added to the series sclerotia placed outside during the winter 
months. 
In no case were apothecia formed, germination always re- 
sulting in the production of tufts of conidiophores. The 
results of these experiments may be summed up by saying 
that in from two to six days, depending on the age of the 
sclerotia, germination took place by the production of 
conidiophores bearing large masses of conidia, in no way 
different from those arising from the vegetative hyphe. 
Cultures inoculated with these conidia gave a typical develop- 
ment, mainly the production of a loose, cottony mycelium 
which formed both conidia and sclerotia anew. 
The sclerotia, after producing a number of these tufts, dis- 
