102 THE CAULIFLOWER. 



and other fungi present, but does not himself con- 

 sider them the direct cause of the disease, which he 

 attributes solely to the abundance of manure and 

 moisture in the soil, and an excess of water in the 

 plant, at a time when it is subject to sudden 

 changes of temperature. Beyond a doubt, how- 

 ever, the real cause of the disease is the presence 

 of one or more fungi, whose development is favored 



Upon microscopic examination the vessels are found 

 filled with gum, M. Comes recognizes in this disease 

 all the symptoms of the affection which has been desig- 

 nated under the name humid gangrene. He thinks that 

 it is the same disease which, by German authors, is 

 attributed to the parasitism of Pleospora Napi, Fuckel, 

 or to its conidiferous form, sporidesmium excitosum, 

 Kuehn. But he considers the presence of these para- 

 sites as an accessory phenomenon, as well as that of 

 Cladosporium and Macrosporium Brassicce. In his 

 opinion the true cause of the alteration of the cauli- 

 flower is the humid gangrene, that is to say, a gummy 

 degeneration and putrid fermentation of the tissues, 

 caused by the abundance of manure in the soil and the 

 excess of water in the plant at a time when it is subject 

 to sudden changes of temperature. 



"This disease is not confined to cauliflowers; it is 

 common in all garden vegetables, and is of the same 

 nature as that which attacks tomatoes and which was 

 described by this author in the same journal in 1884." 

 [This disease is also mentioned by Victor Paquet, in his 

 "Plantes Potagers" (London, 1846, p. 243), where it is 

 attributed to stagnant moisture]. 



