HOP APHIS. 
69 
the presence of hordes of the- Blight; and these observations agree 
precisely with those of Mr. G. B. Buckton (our great authority on 
Aphides) as to the circumstances in which they multiply most 
rapidly. I give the passage, as it bears very practically on the 
method in which, where there is great amount of attack, the stinted 
pasturage causes the Fly to come to maturity sooner, consequently 
propagate sooner, and spread more quickly than even in its common 
rapid progress :— 
“ The addition of wings to the viviparous females obviously must 
much facilitate the spread of each species. This modification of form 
does not occur at fixed or stated intervals, but appears to be in some 
measure induced by an over-crowded state of the colony, and with a 
deficiency of food. Gardeners are well aware of the sickly and 
poisoned conditions produced in those plants which are subjected to 
the exhausting and irritating attacks of Aphides. When the nutritive 
juices of the infested plants begin to fail a change commences in the 
larvae of those Aphides which are subsequently born. Swellings occur 
on the sides of the meso- and meta-tliorax” [i. <?., the sides of 
the two ring-like divisions next but one to the head (Ed.)] , “ within 
which the future wings are developed,” &c. Also, “ I have repeatedly 
observed the effect of stinted food in hastening the development of 
wings.”—‘Brit. Aphides,’ by G. B. Buckton, vol. i., pp. 72, 73. 
When once bad attack is established there does not appear to be 
any sure way of getting it under, but we might get hold beforehand, 
if we knew how and where the pest passes the winter. It is not known 
whether the female Aphis of the last autumn brood lays eggs then, 
and dies, or whether she lives sheltered through the winter and lays 
in the spring. I have in the course of the past late autumn and 
early part of the winter searched microscopically for eggs or the 
female under dead Hop leaves, and also on pieces of the Bine and 
pieces of stem, just above and below ground-level, without the 
slightest success. In earth, taken from the neighbourhood of hills or 
plant-centres in ground where the attack was very virulent, sent by 
Mr. Whitehead from Barming, I found a very few bodies, that might 
be portions of skins of eggs, but even if they were so it was impossible 
to say that they were Aphis eggs. 
The only certain way to make out whether the Aphides come up 
from the earth about the Hop-root appears to be some form of the 
plan by which Prof. Biley watched and discovered a portion of the 
method of increase of the Phylloxera , namely, to raise a light wooden 
frame over a plant, fasten some material such as very stout muslin 
over it, which would admit light to the Hop, but at the same time 
secure that no insects get in or out, have a piece of glass fitted at 
some part of the frame to allow of looking in, and then watch. The 
