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the eggs laid by the latter give rise to a similar cycle in 
the following spring. Some Aphides are restricted to a 
particular species of plant, while others have alternate 
hosts. Thus the Hop Aphis winters on damson and flies 
to hops in the spring. F he Elm Aphis goes to the roots 
of Rzbes, the Mealy Plum Aphis to rushes and aquatic 
grasses, and the Bean Aphis to mangolds, poppies, dock, 
etc. Some of the most destructive Aphides are the Bean 
Aphis (Aphis rumicis), Currant Aphides (Rhopalosiphon 
vibis Linn, and Myzus ribis Linn.), Hop and Damson 
Aphis (Phorodon humuli), Apple Aphides (ApAts pomz 
De Geer., Aphis sorbi Kalt., and Aahis jitcha Sand.), 
Plum Aphis (4 p4is pruni Réaum.), Cabbage Aphis (A phzs 
brassicae Linn.), Turnip Aphis (A fAis rapae Curt.), Rose 
Aphides (species of Szphonophora), Woolly Aphis (Schz- 
zoneura lanigera), and others. {n dealing with these pests 
it is important to remember that when using insecticides 
contact insecticides only are of use. Insecticides fre- 
quently do not destroy the eggs and, notwithstanding 
spraying, fresh broods appear from the unaffected eggs. 
hen the leaves of the host plant are curled insecticides 
are of little value, as they do not reach the Aphides 
within. Frequently the undersides of leaves alone shelter 
the Aphides, and spraying must be adjusted so as to 
reach them. The earlier measures are applied after the 
appearance of Aphides, the better the chances are of 
success, before the latter become numerous. 
The Bean Aphis (17) is usually black and very con- 
spicuous; it especially attacks broad beans. It appears 
when the beans commence to bloom and attacks the heads. 
It breeds rapidly, covering the plants with a black sticky 
mass which gradually extends downwards over the stems 
and leaves. A simple and effective’ measure is to pick 
off the infested tops as soon as any Aphides are seen 
thereon, and drop them straight away into a pail of lime. 
Jn bad infestations spite spraying with a knapsack 
sprayer is necessary. [wo applications are desirable and 
are usually successful. The ‘ee Aphis (17) may also 
infest swedes and turnips. It usually appears about 
May, but evidences of injury are not generally noticeable 
until June, when the leaves begin to show blister-like 
areas on the upper surface, while the Aphides are to be 
found in the corresponding hollows on the undersides of 
the leaves. The leaves become yellow and discoloured, 
