A PARASITIC BOTRYTIS ON PEPPER AND LETTUCE, 51 
well-marked hyphae of Botrytis are seen ramifying abun- 
dantly. Very few sclerotia are produced in the stems. 
Since the infection occurred late in the year, it was im- 
possible to make further observations as to the parasitic nature 
of the fungus. There can be no question but that the warm, 
wet weather of October had some influence on the virulence 
of the disease. The Botrytis was obtained in pure culture and 
+ was while trying infection experiments on young seedlings 
of the pepper that it was introduced into the greenhouse, 
eausing a destructive disease of the lettuce. 
The vegetable greenhouse was given over almost entirely 
io the growing of lettuce during the winter months. The 
epidemic was first observed in February, the most obvious 
«symptoms being the drooping of the outer leaves, followed in 
a day or so by the complete collapse of the plants into a slimy 
mass. ‘The first evidence of the disease was a number of small 
brownish spots on the stem next to the ground and on the 
lower leaves. This was soon followed by the wilting and 
drooping of the outer leaves. A day or so later the whole 
plant was affected, the outer leaves falling to the ground, 
only the central head remaining erect. The leaves at this 
stage had the appearance of being scalded. A few days 
later the whole plant collapsed into a fetid, slimy mass. 
The above description is characteristic for most of the 
infected plants. 
At times other plants, to all external appearance healthy, 
fell to the ground. In this case the fungus worked its way 
up through the stem into the center of the head, developing 
there and finally working its way out to the exterior. This 
raethod of infection was rather common. Again another 
type was occasionally noticed, one side of the plant rotting 
away, while the opposite side remained unaffected. 
No conidia are produced until marked decomposition has 
been brought about within the leaves by the mycelium. The 
conidiophores are visible to the eye as small brownish masses 
scattered over the decayed parts. The most profuse develop- 
rent of the conidia takes place on the under side of the leaves 
