Page:Scientific Memoirs, Vol. 1 (1837).djvu/222

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first two species are the only ones upon which we have continued observations; these we proceed to mention. The larva or caterpillar of the first of these two species, the P. Danticana[1], according to Bosc, is comprehended with other species in the environs of Paris under the collective name of larvæ or worms which injure the vine; in Burgundy and the vine provinces it is called Ver-coquin, a denomination which is also sometimes given to the white worm of the Cockchafer, the Spondyle of Pliny. This caterpillar of the Pyralis of the vine is, shortly after its birth, a centimetre in length; its head is black and its body green, and it has a yellow spot on each side of the neck. Its first appearance is about the end of May, but its greatest devastations are made in the middle of June. It cuts the petioles of the leaves in halves, which causes them to wither, and enables the insect to roll them with greater facility. When the leaf first attacked withers, in consequence of the wound which it has made in the petiole, it proceeds to attack another; and thus one of these caterpillars will destroy several leaves, weaken the vine, and prevent the grapes from becoming large and sweet. This insect does not attack the fruit, but destroys the peduncle of the bunch, which, if it do not wither, remains small and without flavour. When the greater part of the leaves are infested, all the bunches are soon in the same condition, because they grow at the bottom of the stem, and it is there that this caterpillar commences its ravages. The butterfly or Pyralis of this caterpillar is of the size of the nail of the little finger; its wings are of a green fulvous colour, with three oblique bands of brown. These Pyralides are most abundant in the month of July. During the day they remain clinging upon the stems, under the leaves, whence they fly upon the slightest approach of danger. Towards the decline of the day, in the dusk, the male seeks the female; but those which leave their retreats at an earlier hour become the prey of the swallows and other insectivorous birds.

I have remarked that Bosc identified the butterfly which he described under the name of Pyralis Vitis with a new species that Fabricius names Pyralis Vitana. This species, as I have said, was described by Fabricius at Paris from a specimen in Bosc's collection; and he adds five or six lines of technical description. M. Coquebert, of Reims, published at the same time four fasciculi of insects, drawn, engraved and coloured from the specimens observed and described by the Danish naturalist in the collections of Paris, and among the number is the Pyralis Vitana or Pyralis Vitis of Bosc. It would appear that no insect ought to be better known than the one we are treating of; this however is not the fact. After a most attentive examination, Duponchel finds the descriptions of Fabricius and Bosc too short, and insuffi-

  1. Bosc, Nouv, Dict, d'Hist. Nat., vol. xxxv. p. 392.