30 HATCH EXPERIMENT STATION. [Jan. 



also occurred abundantly upon greenhouse cucumbers, but 

 was not observed upon the latter plant when grown out of 

 doors. During the past season (1902) muskmelons have 

 been almost a total failure from this cause ; and cucumbers, 

 both in and out of doors, have been generally affected, the 

 fungus being abundant everywhere upon these two plants. 



Thus it appears that for the past three j^ears this fungus 

 has been steadily increasing in its distribution. Its most 

 serious effects in this State have been upon the muskmelon. 

 Scarcely a single melon was obtained this year by most of 

 the growers, the vines being killed com})letely within a few 

 days' time. Experiments in spraying, made in co-operation 

 with this division in several different places, have shown 

 but little gain. It seems quite evident, in fact, that so long 

 as this disease continues to prevail the muskmelon cannot be 

 grown in Massachusetts. The plant is not naturally adapted 

 to our climate, and succeeds at best onl}^ in favored localities. 

 When attacked by disease it succumbs very easily, esi)ecially 

 in such an unfavorable season as the past one has been. 



Upon the cucumber, the disease, while general, is as yet 

 by no means as serious. Out-of-door fields showed the 

 fungus everywhere this year, but the vines remained alive 

 for some time, and the yield did not appear to be seriously 

 diminished. This, however, is but one year's experience. 



The effect of this disease upon greenhouse cucumberiS is 

 perhaps the most miportant consideration of the whole sub- 

 ject. Here is an industry of considerable and very rapidly 

 increasing importance in this State, involving, relative to 

 most other agricultural industries, a large amount of capital. 

 It is one in which success means good profits and failure 

 large losses. No serious obstacle which cannot be over- 

 come has as 3^et been met with, but considerable alarm has 

 been caused by the general appearance of the downy mil- 

 dew. It may be said, however, that thus far no great 

 damage has been evident. It is noticeable that the disease 

 is most serious in the greenhouse upon plants started in 

 August, which is the time of its occurrence out of doors. 

 Those started later in the season or in spring do not seem 

 to suffer. Even when present in the house, the disease does 



