318 BARON WALCKENAER ON THE 



time it effects the greatest injury is about the middle of June. 

 It eats the leaf-stalks half through ; this causes the leaves to 

 wither and to roll up readily. When one leaf dries up, the 

 insect goes to another. One caterpillar destroys a good many 

 leaves ; the vine is weakened, and the grapes prevented from 

 acquiring their full size and sweetness. This caterpillar does 

 not attack the grape, but eats the grape-stalk, so that even if 

 it does not dry up, the fruit is small and without flavour. 

 After most of the leaves are affected, the grapes cannot long 

 escape, because they are thickest towards the bottom of the 

 plant, and it is there these caterpillars commence the work of 

 destruction. 



The moth produced from this caterpillar is about the size of 

 the nail of the little finger. Its wings are of a yellowish green, 

 with three oblique brown bands. 



These moths are most abundant in July. During the day 

 they are to be found on the vine, sitting under the leaves; they 

 are easily disturbed, and fly off on the least alarm. It is in the 

 dusk of the evening that the male seeks his mate ; those who 

 leave their retreats earlier, quickly become the prey of swallows 

 and other insectivorous birds. 



I have before said that Bosc referred the moth he named 

 Pyralis Vitis to a new species which Fabricius named P. Vitana. 

 I have also said it was described in Pai'is by Fabricius, from 

 Bosc's specimen. M. Coquebert has published four plates of 

 insects drawn and coloured from individuals observed and 

 described by the Danish naturalist ; and amongst these is 

 P. Vitana. 



Thus it would seem the insect was well known ; but this 

 was not the case. 



M. Duponchel has not found Fabricius and Bosc's descrip- 

 tions, or the figure of Coquebert, sufficiently exact for the 

 determination of the species. 



The German authors, Frolich, Treitschke, and others, who 

 have paid great attention to this tribe of moths, would appear 

 to think with M. Duponchel on this subject, as they have not 

 mentioned P Vitana, Fab. in any of their voluminous works. 



In this difficulty M. Duponchel has had recourse to Bosc's 

 collection, which now forms a part of our museum. He finds a 

 Pyi'alis there with the name Vitana attached, described by the 



