NOVEMBER, 345 
Good seed of ** Favourite” was scarce at, Slough last spring, and, that 
our obliging’ friend may beable to warrant a few packets to his imme- 
diate ‘friends: for next ‘year’s growth, I) devoted.a dung frame to the 
especial purpose of: growing, some true and unmixed.) Karly in July 
two cuttings: were iridged out, from, which I have just cut three fruit 
whose united lengths made 89 inches. The quantity of seed obtained 
is but small, but its: quality is first-rate., There will be sufficient, 
however, to distribute-among many, of/the best growers around London, 
whose opinions I shall'be much pleased to possess, through Mr, Turner, 
next autumn. 
| \\9 K. 
ee 
N 
ROSE MILDEW. 
Tus malady has much prevailed here this year, and very early in the 
year.. I-am-therefore induced to call attention to the subject, more with 
the hope of ‘eliciting: from, others what it 1s, how it comes, and how it 
may be prevented or cured, than of succeeding in settling these points. 
We are better judges of effects: than of causes, and, often. mistake the 
one for the other, or attribute’-known effects, to. wrong causation. It is 
very probable that I: am about to;commit,this error: it will, however, 
do no harmo ventilate the subject, even if,.1 should elicit correction and 
information from more’ learned natural philosophers... L shall not 
attempt, with more than a glance, to enter upon Fungi generally, but 
shall chiefly confine my observations to Rose, mildew. 
Mildew I believe to be, a parasitical fungus, affecting objects both 
living and: dead, favourable to: its propagation, from within or from 
without. The former may be called. internal, attacking, the plants 
inwardly, and only becoming perceptible, when, haying been taken up 
from the roots into the circulation, it bursts through the surface of the 
plant for the purpose of development and dissemination of its sporules. 
Such is the fungus of Wheat smut, which proceeds from diseased seed ; 
and which, haying entered from the roots into the circulation, finally 
finds development in the ear, and thence sheds its spores and affects its 
neighbours.. This is-one form of internal fungus. ‘There are many 
others of the same internal..kind, that attack leaves, Celery, Pear, and 
Apple trees... Of this internal kind of mildew I do not now propose to 
speak at, length, as I, apprehend that Rose mildew is chiefly, though 
perhaps not solely, an external fungus, establishing itself on the surface 
of the leaves, without having proceeded through, the circulation. That 
it might also proceed, externally I can easily imagine, as in the case of 
Wheat, smuti: and,if, it.does so proceed, I may say in passing, that 
solution of blue. vitriol.in water, which. is.a sure cure for smutty Wheat 
seed, might, be found a good wash to put the roots of Rose-trees into 
previous to, planting, with,a view) of destroying sporules: and even if 
this fungus does not ;proceed through the circulation, but from without, 
the same lotion which jis, destructive of the fungus of Wheat smut, 
might be found. useful to stop the progress of external mildew, if 
outwardly applied to the leaves when affected. Of course, it would not 
be advisable to apply it too strong, or the remedy may prove worse than 
