PESTIFEROUS FUNGI. 
383 
affects its existence. This latter is evidently the only successful mode 
to be adopted if the parasite is to be brought under control, and the 
host-plant saved from its depredations. For the pursuit of this method 
it will be evident that local investigation is indispensable, and that all 
the surroundings must be taken into account. The mere determina- 
tion of a scientific name may be made from a mature fertile specimen, 
without regard to its development; so that there is no hindrance to 
the production of a long and elaborate list of names, but such a course 
leaves the great mystery unsolved — Iiovv is the disease to be met, 
prevented, or eradicated ? This can only be solved effectually by a 
knowledge of the life-history of the offending parasite, and this can 
only be fully obtained at the place of infection. Thus much it is 
necessary to premise in order to show that, in countries where the crops 
have become subject to the attacks of fungus pests, local investigation 
is indispensable, except in such cases as are universal as to parasite and 
host, as well as in manner of attack, and then analogies will prove 
suggestive. 
We are well aware that enormous losses in fruit and grain 
crops may be caused by parasitic fungi if they are permitted to 
establish themselves, either on account of indifference or ignorance. 
W e are also aware that these losses may be largely diminished by active 
measures, if taken in time and pursued perseveringly. Wherever 
orchards or vineyards have suffered, whether in Italy, France, or the 
United States, successful experiments have followed, which have 
resulted, if not in the conquest, certainly in mitigation of the 
disease. It has also been demonstrated that the particular mode of 
tieatment which has succeeded in one locality has not been equally 
successful in another, which indicates that local surrouudings and 
climatic conditions must be taken into account ; and that, although 
one treatment may not succeed, it is possible that another may 
produce excellent results. 
The inference is that not only should the life-history of these 
parasites be clearly ascertained, but also those minor modifications 
winch may result from any peculiar mode of culture, from difference 
ot soil or climatic conditions; and also that a knowledge should be 
acquired of the various remedies which have been tried from time to 
time in other countries, with the view of testing their efficacy and 
recording the results. However much the energy of private indi- 
viduals may accomplish, the knowledge of results is, to a great extent, 
confined to themselves, and the general interests of the community 
are not improved by the expenditure of much capital and labour. In 
countries where well-organised departments of agriculture, experi- 
mental stations, or other official centres are established, all experi- 
ments with their results are fully recorded,, and the records are freelv 
distributed for the benefit of the public. As it is a national loss that 
so many thousands of pounds annually should fall a prey to fungus 
pests, it would be a national advantage to establish organisations for 
the purpose of encouraging experiment, of collecting and distributing 
information, and generally aiding in the mitigation or extirpation of 
insect or fungoid pests which affect national industry. 
It cannot be urged too often the pressing need of distributing 
and disseminating information as to the life-history of the various 
p ant parasites, and, as far as known, of remedies which have been 
