Insects injurious to fruits . jacent tissue, and thus the insects are induced to betakethemselves to fresh portions of the living roots, until at lastthe larger ones become involved, and they, too, literally wasteaway. In Fig. 242 we have the root-inhabiting type, Radidcola,illustrated: a, roots of Clinton vine, showing swellings; 6,young louse, as it appears when hibernating; c, d, antennaeand leg of same; e, /, g, represent the more mature lice. ATTACKING THE ROOTS. 235 It is also further illustrated in Fig. 243, where a shows ahealthy root, 6 one on which the lice are working, c a rootwhich
Insects injurious to fruits . jacent tissue, and thus the insects are induced to betakethemselves to fresh portions of the living roots, until at lastthe larger ones become involved, and they, too, literally wasteaway. In Fig. 242 we have the root-inhabiting type, Radidcola,illustrated: a, roots of Clinton vine, showing swellings; 6,young louse, as it appears when hibernating; c, d, antennaeand leg of same; e, /, g, represent the more mature lice. ATTACKING THE ROOTS. 235 It is also further illustrated in Fig. 243, where a shows ahealthy root, 6 one on which the lice are working, c a rootwhich is decaying and has been deserted by them ; d, d, d, in-dicate how the lice are found on the larger roots; e representsthe female pupa, seen from above, / the same from below, gwinged female, dorsal view, h the same, ventral view, i theantennae of the winged insect, and j the wingless female, lay-ing eggs on the roots; k indicates how the punctiues of thelice cause the larger roots to rot. Most of these figures are FiQ. iiighly magnified, the short lines or dots at the side showingthe natural size. During the first year of the insects presence the outwardmanifestations of the disease are very slight, although thefibrous roots may at this time be covered with the little swell-ings; but, if the attack is severe, the second year the leavesassume a sickly yellowish cast, and the usual vigorous yearlygrowth of cane is much reduced. In course of time the vineusually dies; but, before this takes place, the lice, having littleor no healthy tissue to work on, leave the dying vine and seekfor food elsewhere, either wandering under ground amongthe interlacing roots of adjacent vines, or crawling over the 23G INSECTS INJURIOUS TO THE QRAPE. surface of tlie ground in search of more congenial the winter many of them remain torpid, and at thatseason they assume a dull-brownish color, so like that of the Fig. 243.
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Keywords: ., bookcentury1900, bookdecade1900, bookidin, booksubjectinsectpests
