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 of the abdomen is smooth and of a yellow white; it attains its full growth towards the end of May, and it is then that it destroys the leaves of the vine. It attaches itself to the upper part of the leaf, and if the branch upon which it is found be shaken, it bends itself in the form of a bow by resting upon the two extremities of its body, and drops down upon the earth. The greatest number of these caterpillars that are to be found upon one vine amounts to about ten; they are generally much fewer. Between the 20th and 30th of May this caterpillar spins a cod of long white flocks, in which it remains motionless, and is transformed into a chrysalis from the 5th to the 10th of June. The chrysalis is at first yellow, with black points upon each segment, but at the moment of transformation the colour increases in intensity and is changed into, a deep azure blue. The transformation of the chrysalis into the butterfly generally commences on the 19th of June, and is not concluded till the 25th. This butterfly is the Procris Vitis, or Procris ampelophaga of modern entomologists. Its wings are of a dark colour, approaching to black, and changing into a sombre green; the body is of a blueish green. The Musca brevis often introduces its eggs into the body of the chrysalis of this butterfly; the larvæ of the fly feed on the substance of the chrysalis without altering its exterior, and the chrysalis thus appears to be metamorphosed into a fly instead of producing a butterfly. Each female of this Procris lays about three hundred straw-coloured eggs, of so small a size that they are scarcely visible to the naked eye. Towards the 3rd of July these eggs produce small whitish caterpillars, which are transparent, and covered with almost imperceptible hairs. The caterpillars of this second race are metamorphosed about the 26th of August.

I have myself verified in part the observations made upon the caterpillar of the Pyralis Danticana by Bosc. The habits of the Procris ampelophaga are only known to me from the memoir of M. Passerini. But if the first species be as abundant in Italy as the second, I shall be induced to think that it is to it that the ancients more particularly applied the names of Involvolus, Involvulus, Involvus, and Convolvulus.

IX. Kampe.—Eruca.—Caterpillars of the Sphinx Elpenor, or Sphinx of the Vine,—of the Bombyx purpurea, or Ecaille mouchetée (Spotted Tiger-moth),—and of the Sphinx Porcellus, or Sphinx with red bands.—The other caterpillars that are found upon the vine, and which may occasionally injure it, as well as plants of every other kind, do not belong to the tribe of Tortrices, or Pyralides, nor to the genus Procris. The species which I have most frequently had occasion to remark, are the Bombyx purpurea of Fabricius, the Arctia purpurea of modern naturalists, and the Ecaille mouchctée of Geoffroy, which lives also upon