ATTACKING THE BRANCHES. 



241 



origin ; hence by grafting the more susceptible varieties on 

 these hardier sorts, the ill effects produced by the lice may in 

 some measure be counteracted. The roots recommended to be 

 used as stocks are those of Concord, Clinton, Herbemont, Cun- 

 ningham, Norton's Virginia, Rentz, Cyuthiana, and Taylor. 

 The Clinton, one of the varieties recommended, is particularly 

 liable to the attacks of the gall-producing type of Phylloxera, 

 but the lice are seldom found to any great extent on its roots, 

 and the vine is so vigorous a grower that a slight attack would 

 not produce any perceptible injury. 



Fig. 248. 



ATTACKING THE BRANCHES. 



No. 126. — The Grape-vine Bark-louse. 



Pulvinaria innumerabilis Kathvon. 



During the month of June there are sometimes found on 

 the branches of the grai)e-vine, brown, hemispherical scales, 

 from under one end of which there protrudes 

 a cotton-like substance, which increases in 

 size until the beginning of July, by which 

 time it has become a mass about four times 

 as large as the scale. (See Fig. 248.) This 

 cottony matter contains the eggs of the in- 

 sect, and very soon there issue from it minute, 

 oval, yellowish-white lice, which distribute 

 themselves over the branches, to which 

 they attach themselves, and shortly become 

 stationary, sucking the juices. This species 

 is believed to be the same as the European 

 scale-insect of the vine. These scales are 

 not usually found in any great abundance, 

 and may be readily scraped off with a knife 

 or other suitable instrument, which should 

 be done before the young lice escape. 



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