Insects injurious to fruits . ATTACKING THE LEAVES. 293 mi/ia, and on cutting into the galls they are found to be hollow,each containing a pale-orange larva. It is probable that thelarva enters the earth to transforni to the pupa, and that the flyis produced the following season. No. 167.—The Grape-vine Filbert-gall. Vitls coryloides AValsh & .Riley. In this instance a rounded mass of galls from one and alialf to two and a half inches in diameter springs from acommon centre at a point v/here a bud would naturally befound. The mass (see Fig. 304) is composed of from ten to Fia. . forty opa
Insects injurious to fruits . ATTACKING THE LEAVES. 293 mi/ia, and on cutting into the galls they are found to be hollow,each containing a pale-orange larva. It is probable that thelarva enters the earth to transforni to the pupa, and that the flyis produced the following season. No. 167.—The Grape-vine Filbert-gall. Vitls coryloides AValsh & .Riley. In this instance a rounded mass of galls from one and alialf to two and a half inches in diameter springs from acommon centre at a point v/here a bud would naturally befound. The mass (see Fig. 304) is composed of from ten to Fia. . forty opaque, woolly, greenish galls, which have a fleshy, juicy,sub-acid interior, each with a single central, longitudinal cell,one of which is shown at c in the figure, about a quarter of 294 INSECTS INJUR TO US TO THE GRAPE. Fig. 305. an inch long and one-fourth as wide, containing a solitaryorange-yellow larva, about one-eighth of an inch long. Thisis also the larva of an undetermined species of Cecidomyia,a family the members of which may be recognized in thelarval state by a peculiar appendage known as a breast-boneattached to the under side near the head. In this species itis almost Y-shaped, as shown at a in the figure; the diverging branches terminate in two pro-jecting points, which may beextended at will, and which areprobably used by the larva inabrading the soft tissues of thegall so as to cause an exudationof sap, on which the larva flies belonging to this genusare usually of a dull-black color,like that shown in Fig. 305, a,which represents a female fly; the
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Keywords: ., bookcentury1900, bookdecade1900, bookidin, booksubjectinsectpests
