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sues and tlie number of conidial tufts visible on the surface seems to 
depend to a considerable extent on the amount of moisture in the air 
and on the length of time the peach has been affected. From these little, 
dusty, ash-colored tufts, which every peach grower must have observed, 
the infection is very readily transmitted to healthy peaches. Rains, 
winds, birds, insects, etc., all help to disseminate the spores and those 
which find suitable lodgment are very likely to germinate and extend 
the disease if the atmospheric conditions are at all favorable. Of course 
myriads of spores miscarry and other myriads perish before germina¬ 
tion or during its progress, otherwise the peach and kindred fruits must 
long since have perished from the earth. Ample provision, however, 
has been made for the perpetuation of this parasite by endowing it with 
a fecundity which more than compensates for the small size and perish¬ 
able nature of its spores. After some weeks, however, the conidia 
cease to be produced and the ash-gray tufts gradually disappear. 
The disappearance of the conidial tufts is not, however, the end of 
the fungus. This winters over as a resting mycelium in the destroyed 
peaches w r hich have either fallen to the earth or still hang upon the 
branches in a dry, wrinkled, mummified state. Early in the spring, if tlie 
atmospheric conditions are favorable, the fungus awakes to renewed 
activity—another crop of conidia is produced from new tufts borne on 
the old mycelium and the work of destruction begins anew. In the 
spring of 1889 I witnessed this for the first time, and was able to settle 
beyond doubt that the fungus winters over in the decayed fruits, es¬ 
pecially in those which remain hanging upon the trees. This fact is one 
of great practical importance. The ordinary spores (conidia) being of a 
perishable nature it has occurred to many mycologists that Monilia 
must .exist during a portion of the year under some other form—one 
capable of passing in safety through the inclement season. With this 
thought in mind I had been watching the fungus very narrowly for 
several seasons, but all to no purpose until May of this year. Then, 
thanks to a very rainy week, I came suddenly upon the explanation I 
was seeking. 
Earlier in the year, when the peaches were in blossom and beginning 
to put forth their foliage, I was in the Delaware orchards, and was 
greatly perplexed to find the Monilia appearing suddenly everywhere 
on the blossoms and young fruit. This was first observed about April 
29, in moist weather, soon after an unprecedentedly heavy and pro¬ 
longed rainfall.* 
The orchards blossomed abundantly, but the greater part of the peach 
*At Dover it poured continually for tweuty hours (8 p. m. of 25th to 4 p. m. of 
2Gtli), and reports from the upper portion of the peninsula also indicated a very heavy 
rainfall. It also rained in showers on the 27th, all day. The precipitation at Dover 
from the first storm must have been at least six iuches. A few peach orchards were 
then in full blossom, but the majority were a day or two in advance and nearly or 
quite out of blossom. 
