. The book of the garden. Gardening. ESCULENT-ROOTED PLANTS.—THE TURNIP. 191 long, or longev, than any two of the other joints taken together ; the remainder decreasing some- what in length to the terminal one, which is large and oyai. The flies, which appear in the early part of summer, and deposit their eggs on the young turnip plants, have probably survived the winter under groimd in the pupa state, en- veloped in their cocoon. Emerging from them, as soon as the milder weather is confirmed, in their winged state, the females immediately lay their eggs, after which they very soon die. The eg
. The book of the garden. Gardening. ESCULENT-ROOTED PLANTS.—THE TURNIP. 191 long, or longev, than any two of the other joints taken together ; the remainder decreasing some- what in length to the terminal one, which is large and oyai. The flies, which appear in the early part of summer, and deposit their eggs on the young turnip plants, have probably survived the winter under groimd in the pupa state, en- veloped in their cocoon. Emerging from them, as soon as the milder weather is confirmed, in their winged state, the females immediately lay their eggs, after which they very soon die. The eggs appear, for the most part, to be placed round the outer margin of the rough leaves. In favourable weather they are hatched in a very short time, and the young larvaa immediately commence their attack on the plant. At first these larvae are of a deep black colour, and, of course, small size; but they grow rapidly, and in course of a few weeks attain their full dimen- sions. In the course of their growth they change their skin several times, and most of their moult- ings are attended with a slight change in their colour. After casting their last skin, they are of a dark lead or slate-grey colour, paler ; Mr Curtis states that they are sometimes green, a colour which we never saw them assume, for in general they are not liable to much variation in this respect. Like most of the other larvae of their tribe, when touched or in any way disturbed, they coil themselves up and remain motionless. When full grown, the larvae cease to eat, and allow themselves to drop from the plant that nourished them to the ground, in which they usually bury themselves; or they take shelter among rotten leaves, moss, &c. When examined after a short time, they are found to be com- pletely enclosed in a cocoon composed of two distinct layers of silk. The inner layer is of a fine satin lustre; and when the cocoon is opened, it appears as if it had been washed with a solu- tion of silve
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Keywords: ., bookcentury1800, bookdecade1850, booksubjectgardening, bookyear18
