472 



Antheacnose of the Cucumbek Undee Glass. [Aug., 



(6) The examination of " flats " was unsuccessful in ob- 

 taining positive evidence of their transmission of this fungus, 

 but observations upon the incidence of this disease in com- 

 mercial nurseries indicate the probability that it may fre- 

 quently be carried in this way. 



(7) The examination of straw manure has shown it to be 

 such an important source of infection, that special attention 

 was given to it, and straw manure from the following sources 

 was examined : — 



(a) Straw manure fresh from country farms. 



(b) Straw manure from country farms after lying in a heap adjacent 

 to a heap of old diseased cucumber plants. 



(c) Straw manure from localstables. 



(d) Straw manure from London. 



The heaps of manure were carefully searched and suspected 

 material taken to the laboratory for further study. Suspensions 

 were also prepared by shaking 1 lb. of manure with 1 gallon of 

 water for five minutes and straining through a fine wire sieve. 

 The liquid obtained was sprayed over young cucumber plants 

 kept in a humid chamber. C. oligochaetiim was found in nine 

 different samples, and in one of these the pink spore masses 

 appeared on half-decayed straw at the surface of the heap. In 

 no case was the fungus found in manure fresh from country 

 farms or local stables. In five cases it was found in the manure 

 heaps adjacent to those of decaying cucumber remains, and in 

 four cases in manure freshly imported from London stables. 



The possible importation of disease in manure from town 

 stables, is important to growers, and especially to those of glass- 

 house produce. Much diseased fruit is sold in East London and 

 Dr. W. B. Brierlev, of Bothamsted Experimental Station, in- 

 forms the writer that cucumbers badly attacked by C. oligo- 

 chaetum are frequently to be seen on street stalls in those parts, 

 the most diseased specimens frequently being thrown into the 

 roadway and trodden under foot. This infection may gain 

 access to stables and thence return to the grower. 



The writer's investigations have shown that in nurseries, 

 where C. oligochaetum has appeared for the first time, it has in 

 certain cases been imported in the straw manure and further 

 investigations are necessary to determine the best way of sterilis- 

 ing the manure without reducing its value. 



Other important sources of infection are the water supply and 

 the clothes of workers in the infected nurseries, the latter having 

 been found to be a most important method of diserse trans- 

 mission in the Lea Valley. 



{To be concluded.) 



