208 



THE AMERICAN 



INSECTS INJURIOUS TO THE GRAPE-VINE.- 



Tlie Grape Leaf-folder. 



( Desmia maculalis, West 



Tlie subject of this sketch has long been known 

 to depredate on the leaves of the Grape-vine in 

 many widely separated parts of North America. 

 It is not uncommon in Canada West, and is 

 found in the extreme southern parts of Georgia. 

 It appears to be far more injurious, however, in 

 the intermediate country, or between latitude 

 35° and 40°, than in any other sections, and in 

 Southern Illinois and Central Missouri proves 

 more or less injurious every year. It belongs to 

 the same family (Asopid^) as our notorious 

 Clover-worm, which attacks our clover stacks 

 and mows. It was first described and named 

 by Westwood*, who erected, for it, the genus 

 Desmia. 



This genus is characterized by the elbowed or 

 knotted appearance of .the g antennse, in con- 

 trast with the smooth, thread-like ? antennie ; 

 the maxillary palpi are not visible, while the 

 compressed and feathery labial palpi are recurved 

 against the eyes, and reach almost to their sum- 

 mit; the body extends beyond the hind wings. 



The moth of the Grape Leaf-folder is a vei-y 

 pretty little thing, expanding on an average 

 almost an inch, with a length of body of about 

 one-third of an inch. It is conspicuously marked, 

 and the sexes differ sufficiently to have given 

 rise to two names, the female having been named 

 Botys hicolor. The color is black, with an 

 opalescent reflection, and the under surface differs 

 only from the upper in being less bright ; all the 

 wdngs are bordered with wliite. The front wings 

 of both sexes are each furnished with two white 

 spots ;t but while in the male (Fig. 127, 4) there 

 is but one large spot on the hiud wings, in the 

 female (Fig. 127, 5) this spot is invariably more 



•Mag. Zool., 1 

 tMr Glover, i 

 ,ayB that tlie m 

 utside of each spi. 



liDi't for 18.^4, p. 79, 

 nark of white on the 

 ,■,1,1 6,ibi.l., is very 

 distinct. In dozens ul,,|.c-cui.ijio l.i.aiii Illinois and Mi.<!snuri 

 1 such mark appears, tlioujjh tlit 



or less constricted in the middle, especially above, 

 and is often entirely divided into twci distiiicl 

 spots. The body of the male has but one distiiut 

 transverse band, and a longitudinal wliilr <la.>li 

 ■ H e\tremit\ superiorly, while that of (ho 

 female has two wliite bands. The 

 antennae, as already stated, are still 

 more characteristic, those of the male 

 being elbowed and thickened near 

 the middle, while those of the female 

 are simple and thread-like. 



There are two broods in this lati- 

 tude — and probably three farther 

 '^ south — during the year; the first moths 



A white appearing in June, the second in 



August, and the worms produced from these last 

 liibernating in the chrysalis state. The eggs are 

 scattered in small patches over the vines, and 

 the worms are found of all sizes at the same time. 

 These last change to chrysalids in 24 to 30 days 

 from hatching, and give forth the moths in about 

 a week afterwards. 



The worm (Fig. 127, 1) folds ratlier tlum rolls 

 the leaf, by fastening two portions together 

 by its silken threads ; and for this reason, in con- 

 tradistinction to the many leaf-rollers, may be 

 popularly known as the "Grape Leaf-folder." 

 It is of a glass-green color,* and very active, 

 wriggling, jumping and jerking either way at 

 every touch. The head and thoracic segments 

 are marked as at Figure 127, 2. If let alone 

 these worms will soon defoliate a vine, and the 

 best method of destroying them is by crushing 

 suddenly within the leaf, with both hands. To 

 prevent their appearance, however, requires far 

 less trouble. The chrysalis is formed within the 

 fold of the leaf, and by going over the vineyard 

 in October, or any time before the leaves fall, 

 and carefully plucking and destroying all those 

 that are folded and crumpled, the supply for the 

 following year will be cut off. This should be 

 done collectively to be positively effectual, for 

 the utmost vigilance will avail but little if one is ' 

 surrounded with slovenly neighbors. 



We believe this insect shows no preference for 

 any particular kind of grape-vine, having found 

 it on well nigh all the cultivated, as well as the 



invL-U ' A. 4u'u..,' a .■.Miu-,.u., .,r piiik Uul IkIu..; changing 

 .. ilii\>:ili~. which latter is ot Ilie normal culor, size and 

 iirin ijV bigure l'J7, 3, and has at the tail several very minute 

 urved hooks, joining and forming into a point 



