BY WHICH THE VINE IS INFESTED. 219 



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 butter- 

 fly 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 larvae of the fly feed on the substance 

 of the chrysalis without altering its exterior, and the chrysalis thus ap- 

 pears 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 cater- 

 pillar 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 parti- 

 cularly applied the names of Involvolus, Bivolvtdus, Involvtis, and 

 Convolvulus. 



IX. Kampe. — Eruca. — Caterpillars of the Sphinx Elpenor, or 

 Sphinx of the Vine, — of the Bombyx purpurea, or Ecaille mouchet^e 

 (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 na- 

 turalists, and the Ecaille mouchctee of Geoff'roy, which lives also upon 



Vol. I. — Part II. Q 



