1 62 Notes and Gleanings. 



of a fungus, although, so far as I am aware, not yet described and named. 

 Plants infested by it manifest signs of being held in the embrace of an enemy 

 unwilling to quit its hold so long as life remains. The parts affected have a dark 

 and singed appearance, every way resembling fungous growth, and after a while 

 may be reduced to powder by simply rubbing with the fingers. It generally an- 

 nounces its presence by first attacking the most tender leaves and delicate buds ; 

 and, as it continues to unfold itself, the whole plant becomes dry and crisp. Un- 

 like many fungi, however, w^hich grow upon plants, its ravages are not confined 

 to the leaves and stems alone, but extend to the roots as well ; and, from certain 

 indications, I am inclined to believe these organs quite often are the first to be- 

 come diseased. I have at least observed one or more diseased roots on almost 

 every plant examined ; and in bad cases they have precisely the same appear- 

 ance as the other parts aflfected ; but whether from aggregations of fully-developed 

 fungi, or blisters caused by the growth of mycelium under the skin, I am unable 

 to say. It can hardly be disputed that the fungus which causes smut in wheat 

 " enters the plant from infested seed on its first germination, and is propa- 

 gated not only by its seeds and spores, but by still smaller granules from its 

 mvcelium." If this is not so, why are farmers in the countries where this dis- 

 ease is prevalent at such pains in selecting their seed, and subjecting it to the 

 process of " pickling " before sowing ? Those who practise this precautionary 

 measure do not claim for it the power of entirely preventing the disease ; but 

 experience has taught them, that, when seed is so treated, their crops are com- 

 paratively clean. It therefore seems in accordance with analogy to suppose the 

 disease in the verbena proceeds from a similar cause, operating in much the 

 same way, though ditferent as regards the products which so injuriously affect 

 the plants concerned. And further : it may be stated that diseased roots exhibit 

 traces of dark lines running up toward the stem, and gradually assuming an ap- 

 pearance which indicates, that, whatever process has been at work, the cellular 

 structure has been most hurtfully interfered with, — a work which the spawn of 

 fungi is well able to do. 



But, although, this view pdints in the direction of the poison entering the 

 plants by the roots, it does not necessarily follow that this is the only way by 

 which they might become infested : for, even supposing this to be the case, it is 

 just as likely that the spores carried about by the atmosphere will germinate 

 and grow wherever a suitable nidus is found ; while the conditions required 

 might be in the ground, or on the roots, as well as on the leaves of the plant. 

 Observation teaches that the spawn of many fungi grow and do much harm in 

 circumstances where they do not produce spores at all, as in the case of dry-rot 

 in timber and the fairy-rings of the superstitious ; while quite a large class, '"the 

 minute pests of plants, bear spores in vesicles without definite arrangement," 

 and these might be produced wherever the thread-like mycelium extends. For 

 aught, therefore, we know to the contrary, as well as for reasons already stated, 

 the verbena may receive with its food the poison which kills it ; and that poison 

 in a semi-active state may be the cause of the hardening and curling of the 

 leaves, as is often the case even when there is no discoloration. 



Notwithstanding these views, however, I am far from supposing that sufficient 



