Aphis and other insect pests.  To economise the liquid it is advisable to fill a pail or tub and immerse the plants individually.  Take one in the right hand and spread the fingers of the left hand over the surface of the soil to prevent an accident; then turn the plant over and plunge the foliage in the liquid, moving it up and down briskly two or three times.  If this is not practicable syringe the plants, taking care to wet the leaves on both sides.  On the following day syringe with pure soft water.

Rose trees may generally be cleansed of fly by means of the garden engine and pure water only, the essential point being to direct the water on the trees with some amount of force for several evenings in succession whenever the fly threatens to obtain the mastery.

Soft soap dissolved in water makes a cheap and effectual wash for exterminating all kinds of Aphis, and to these ingredients quassia may with advantage be added.  One pound of soft soap will suffice for ten gallons of water, into which stir the extract obtained by boiling one pound of quassia chips in water.  Pot plants can be dipped in it as already advised, or the solution may be applied by means of the syringe.  On the following day the plants should be cleansed with pure soft water.

==The Bean Aphis==, also known as the Bean Plant Louse, or Black Dolphin =(Aphis rumicis)=.  Our illustration shows the wingless female and pupa natural size and magnified.  The pupa is black with greyish white mottlings, while the female is deep greenish black in colour.  This insect commonly attacks the young shoots and tops of Broad Beans.  It is well to cut off the infected tops and burn them.  Should the attack be repeated spray the Beans with a solution of soft soap and quassia.

[Illustration:  Bean aphis=Aphis rumicis= (pupa and female)]

==The Pea Siphon-Aphis== (=Siphonophora pisi=, Kalt).—­Among the aphides peculiar to vegetables this is one of the most common.

[Illustration:  Pea siphon-aphis=Siphonophora pisi=]

Our illustration shows the natural size and an enlarged figure of the greenish-winged and green-tinted wingless females, as produced, not from eggs, but alive and developed.  This insect is occasionally very destructive to Pea crops.

[Illustration:  American blight=Schizoneura lanigera=]

==American Blight==, or ==Woolly Aphis==, generally appears first on trees grafted on dwarfing stocks, particularly the bad forms of the Paradise Apple.  Rapidly the mischief spreads, healthy trees become infested, and unless checked an orchard is speedily ruined.  Andrew Murray says that in bad cases of American Blight it is sometimes necessary to root up and burn all the trees, and let the ground remain unplanted for a year or two.  Fruit trees should be examined periodically for this pest, and immediately the woolly spots are detected small tainted boughs