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and in late summer the plants may swarm with the 
Insects. In the early stages of attack benefit is derived 
by cutting off the blistered or yellowish leaves and 
destroying them. Later on dusting with soot is worthy 
of a trial, and spraying is practicable on a small scale in 
garden plots. All methods of cultivation tending to 
produce vigorous growth are serviceable, and copious 
watering in dry weather, which favours Aphid multiplica- 
tion, is of great value. Aphis pomi and A. sorbi (4) which 
attack the apple, puncture the leaves and cause them to 
curl and become discoloured, while A. fitchzz attacks the 
blossoms and buds, but does not usually cause leaf 
curling. For all thtee species it is important to spray: 
about the middle of April, when the eggs have hatched 
and the young are most vulnerable. The Rose Aphides 
are familiar to every gardener, and there are three species 
commonly met with. Siphounophora dirhoda Wik. is 
stated to migrate to grasses, Polygonum and _ wheat, 
S. rosae Reau. to teazles, while S. rosarum Wik. appears 
to have no alternate host. If only the latter species be 
present one or two early sprayings are sufficient, but with 
the other two species additional applications are some- 
times necessary owing to fresh infections from their 
other plant hosts. Paraffin should never be used on rose 
trees, and only 4lb. of soft soap should be mixed to Io 
gallons of water in the quassia wash referred to further 
on. When only affecting a few twigs here and _ there, 
Rose Aphides can be readily killed by momentary immer- 
sion in a vessel of water just too hot to keep the hand 
in, without injury to the plant (10). Of the Currant 
Aphides (4), &. 726is produces reddish blister-like galls 
on the surface of the leaves, while M/. rvibis causes the 
leaves to curl up especially those on the terminal shoots. 
Both species as they become numerous are difficult to deal 
with, as they are protected in the hollows of the blisters 
on the undersides of the leaves, or within the curled up 
leaves. One of the effects of their presence is the fre- 
quent falling of the fruit before maturity. Both species 
deposit their eggs under the broken rind or upon it, 
chiefly on twigs of the previous year’s growth. Both 
currants and gooseberries are attacked, and M. rzbzs 
especially frequents black currants. Early spraying in 
April is the best measure, and care must be exercised in 
order that the fluid reaches the undersides of the leaves. 
