. Insects injurious to fruits. Illustrated with four hundred and forty wood-cuts. Insect pests. 294 INSECTS INJURIOUS TO THE GRAPE. Fig. an inch long and one-fourth as wide, containing a solitary orange-yellow larva^ about one-eighth of an inch long. This is also the larva of an undetermined species of Gecidomyiaj a family the members of which may be recognized in the larval^ state by a peculiar appendage known as a breast-bone attached to the under side near the head. In this species it is almost Y-shaped, as shown at a in the figure; the diverging branches terminate in two pro- jecting
. Insects injurious to fruits. Illustrated with four hundred and forty wood-cuts. Insect pests. 294 INSECTS INJURIOUS TO THE GRAPE. Fig. an inch long and one-fourth as wide, containing a solitary orange-yellow larva^ about one-eighth of an inch long. This is also the larva of an undetermined species of Gecidomyiaj a family the members of which may be recognized in the larval^ state by a peculiar appendage known as a breast-bone attached to the under side near the head. In this species it is almost Y-shaped, as shown at a in the figure; the diverging branches terminate in two pro- jecting points, which may be extended at will, and which are probably used by the larva in abrading the soft tissues of the gall so as to cause an exudation of sap, on which the larva feeds. The flies belonging to this genus are usually of a dull-black color, like that shown in Fig. 305, a, which represents a female fly; the antenna of a male is seen Tit b. The gall is common in July ; the larger-sized specimens bear some resemblance to a bunch of filberts or hazel-nuts, hence the name filbert-gall. No. 168.—The Grape-vine Tomato-gall. Vitis tomatos Riley. These galls form a mass of irregular, succulent swellings on the stem and leaf-stalks of the grape-vine (see Fig. 306), very variable in size and shape, from the single, round, cran- berry-like swelling to the irregular, bulbous protuberances which look much like a grouj) of diminutive tomatoes. They have a yellowish-green exterior, with rosy cheeks, and some- times are entirely red; the interior is soft, juicy, and acid. Each gall has several cells, as shown at a in the figure, and in each cell there is an orange-yellow larva, which, before the gall has entirely decayed, enters the ground, where it changes to a chrysalis, and finally emerges as a pale-reddish gnat, with black head and antennae, and gray wings. This fly also be-. Please note that these images are extracted from scanned page images that may have been digitally enha
Size: 1752px × 1427px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, bookpublisherphila, bookyear1883
