Insects injurious to fruits . No 168.—The Grape-vine Tomato-gall. Vitis tomatos Riley. These galls form a mass of irregular, succulent swellingson 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 protuberanceswhich look much like a group of diminutive tomatoes. Theyhave a yellowish-green exterior, with rosy cheeks, and some-times are entirely red; the interior is soft, juicy, and gall has several cells, as shown at a in the figure, andin each cell there is an orange-ye
Insects injurious to fruits . No 168.—The Grape-vine Tomato-gall. Vitis tomatos Riley. These galls form a mass of irregular, succulent swellingson 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 protuberanceswhich look much like a group of diminutive tomatoes. Theyhave a yellowish-green exterior, with rosy cheeks, and some-times are entirely red; the interior is soft, juicy, and gall has several cells, as shown at a in the figure, andin each cell there is an orange-yellow larva, which, before thegall has entirely decayed, enters the ground, where it changesto a pupa, and finally emerges as a pale-reddish gnat, withblack head and antennae, and gray wings. This fly also be- ATTACKING THE LEAVES. 295 longs to the family Ceddomyia, and is known to entomologistsas Lasiopiera vitis of Osten Sacken. Tiie larvae are liable to be attacked by a parasite, and also by a species of Thrip, which invade the cells and destroy theinmates. No. 169.—The Grape-vine Apple-gall> Vitis pomum Walsh & Riley. This is a globular, fleshy, greenish gall, about nine-tenthsof an inch in diameter, which is attached by a rough base, 296 INSECTS INJURIOUS TO THE GRAPE. like that of a hazel-nut, to the stem of the vine. On its ex-ternal surface there are longitudinal depressions, which dividethe gall into eight or nine segments. The interior is fleshyfor about one-eighth of its diameter, then follow a series ofelongated cells, each divided into two by a transverse partition,the lower being the shorter of the two. Fig. 307, a, represents the exterior of theFig. 307. .- e gall; 0, a section oi the same, showingits interior cell is occupiedby a single larva ofa bright-yellow color,with a chestnut-brown,Y-shaped breast-bone,which eventually produces a gall-fly belonging to the genusCeddomyia. This gall sometimes varies in form, being occasionall
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