123 
Aside from pycnidia on tlie leaves, the development of Fencstclla 
platani is as follows : 
The ascospores give rise to a mycelium which immediately cuts oft 
gonidia—the Acrostalagmus stage. Later the mycelium develops into 
a stroma in which pycnidia are formed—the Gytispora stage. Finally 
perithecia break out of the stroma between the pycnidia—the Fenestella 
stage. Cultures of Acrostalagmus reproduced the same gonidial form, 
and no pycnidia ; cultures of Gytispora both artificial and natural 
yielded the same pycnidia again. Under favorable circumstances, how¬ 
ever, perithecia might be developed. 
If the pycnidia that occur on the leaves really belong to Fenestella , 
then this fungus possesses both a parasitic and saprophytic cycle of 
development. The uncertainty which still exists in regard to this 
makes it undesirable to go farther in order to draw general conclusions. 
(To be continued.) 
PEACH ROT AND PEACH BLIGHT. 
(Monilia frucligena , Persoon.) 
By Erwin F. Smith, Sc. D. 
For six years my attention has been drawn repeatedly to the serious 
losses resulting from the parasitism of Monilia fructigena upon plums 
and other stone fruits, and during the last three years my opportunities 
for observing its effect upon the peach have been unrivaled. These op¬ 
portunities occurred principally in the great peach district lying between 
the Chesapeake and Delaware Bays. There, in the prosecution of the 
peach-yellows investigation, I have examined hundreds of orchards at 
all seasons of the year, and have incidentally made some very interest¬ 
ing observations on other diseases of the peach, particularly that re¬ 
sulting from the Monilia. It has also been my fortune to see this dis¬ 
ease in the peach-belt of southwestern Michigan. 
This fungus is more common, and far more destructive than any other 
observed on the peach in this country. It is rarely absent from the or¬ 
chard, and in rainy weather it frequently destroys from one-half to three- 
fourths of the crop, in some cases the entire crop. Under its influence 
the fruit quickly loses its normal color and flavor,-and becomes an en¬ 
tire loss to the grower. As the fungus invades the healthy tissues of 
the fruit the latter become leather-colored, or dark brown, and the peach 
is said to “rot,” although, as Von Thiimen first pointed out, the change 
is not strictly a rot. For the purposes of this paper it will, however, be 
convenient to follow the well-established popular usage and speak of 
this disease as the “ peach rot. ” 
So rapid are the changes induced by this fungus that sometimes the 
