. Cooperative economic insect report. Beneficial insects; Insect pests. - 564 - Hosts: Cultivated and wild crucifers, sugar beet, carrot, flax and grape. Life History and Habits: There are normally two generations a year in Germany and Italy, but three generations are reported in Switzerland. The first adults appear in May and deposit eggs in incisions in the lower surface of the leaves, up to 4 eggs per leaf. Each female may lay 10 to 23 eggs a day and survive for about 14 days. The eggs hatch in 4 to 7 days in Germany. The newly-hatched larvae feed on lower surface of leaves, but migrate to
. Cooperative economic insect report. Beneficial insects; Insect pests. - 564 - Hosts: Cultivated and wild crucifers, sugar beet, carrot, flax and grape. Life History and Habits: There are normally two generations a year in Germany and Italy, but three generations are reported in Switzerland. The first adults appear in May and deposit eggs in incisions in the lower surface of the leaves, up to 4 eggs per leaf. Each female may lay 10 to 23 eggs a day and survive for about 14 days. The eggs hatch in 4 to 7 days in Germany. The newly-hatched larvae feed on lower surface of leaves, but migrate to upper surface as they mature and feed on the edges. Larvae become full-grown in 20 to 25 days. After fifth molt, they spin cocoons in the soil in which they overwinter. Pupation, lasting 4 to 8 days, occurs in the spring. Pupation in the summer generation requires from 15 to 20 days. Either second or third generation overwinters. Description: The adults are relatively slim, averaging 6 to 8 mm. in length. The males are invariably smaller than the females. The body is usually bright orange, with the brillant color of the abdomen partly concealed normally by the wings. The head is black with the exception of the mouth parts, which are yellowish. The coloration of the thorax is an important characteristic of the species. The pronotum and areas of the mesothorax are reddish-yellow with a transition to the more yellowish abdomen. The raesonotum is black and the metathorax is largely black. The wings are smoky-yellow brown, especially towards the body. The terminalia are also important taxonoraic characters. Newly-deposited eggs are bean-shaped and whitish-yellow, later turning dirty- gray; average mm. to mm. in length. The larvae are without pubescence, predominantly blue-black in later instars with an especially darkly-marked median dorsal line, which is bordered on either side by a strong black stripe. The ventral surface is generally gray-black. Fifth-instar larvae meas
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