1 904-] 



Sclerotium Disease. 



555 



herd. In this way a herd will be submitted to a process of 

 grading-up, which cannot fail to react on the quantity and 

 quality of the milk produced. Full particulars of the arrange- 

 ments made by the colleges for this purpose will be published 

 in a later number of this Journal. 



Jn the majority of instances, parasitic fungi are limited in 



their attacks to one or at most a few kinds of closely related 



plants. The sclerotia-forming fungi are, 



Sclerotium however, a marked exception to this rule, 

 Disease. ... 



and attack indiscriminately almost every 



kind of plant. Among economic plants that suffer are potatoes, 

 turnips, carrots, peas, beans, cucumbers and marrows. 



Decorative plants also suffer to a considerable extent, especially 

 snowdrops, lilies, tulips, and allied kinds propagated by bulbs. 

 Weeds are also attacked. 



In addition to growing as parasites on living plants, these fungi 

 flourish vigorously on decaying vegetable matter, and can 

 practically be found on every heap of decaying plants, from 

 whence spores are scattered far and wide, some forming new 

 colonies on dead and others on living plants. 



Several kinds of Sclerotinia are parasites, but as the general 

 appearance and mode of life, and also the method of treatment, 

 are si milar for all, it is not necessary to discuss these separately. 



An early indication of the disease is wilting and yellowing of 

 the leaves, followed by drooping of the stem when present. 

 When this stage is reached, the stem or leaves just above ground 

 are covered with a whitish fluffy mould, which soon changes to 

 a brownish colour and liberates clouds of minute spores when 

 rubbed. This is the earliest and most frequent form under which 

 the fungus appears, and is called the Botrytis stage. In potatoes, 

 beans, &c, the fungus passes up the inside of the stem, and there 

 forms numerous solid bodies, varying in size from a turnip seed 

 to a grain of wheat. These bodies, called sclerotia, are at first 

 pale in colour, becoming black outside when mature. In this 

 condition sclerotia remain until the following season, when, 



