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in spring, when they deposit their eggs on the young leaves of the vine. The larvae are 

 hatched during the month of June, and resemble the perfect insect, except in size and in 

 being destitute of wings. During their growth they shed their skins, which are nearly 

 white, several times, and although exceedingly delicate and gossamer-like, the empty skins 

 remain'for some time attached to the leaves. The insects feed together on the under 

 side .of the leaves, and are very quick in their movements, hopping briskly about by 

 means of the hind legs, which are especially fitted for this purpose. They have a peculiar 

 habit of running sideways, and when they see that they are observed on one side of a 

 leaf they will often dodge quickly around to the other. They are furnished with a sharp 

 beak or proboscis, with which they puncture the skin of the leaf, and through which they 

 ;suck up the sap, the exhaustion of the sap producing on the upper surface yellowish or 

 brownish spots. At first these spots are small and do not attract much attention, but as 

 the insects increase in size the discoloured spots become larger, until the whole leaf is 

 involved, when, changing to a yellowish cast, it appears as if scorched, and often drops 

 from the vine. Occasionally the vines become so far defoliated that the fruit fails to 

 ripen." 



" As the leaf-hopper enters the second stage of its existence, corresponding to the 

 chrysalis state in other insects, diminutive wings appear, which gradually grow until fully 

 matured, the insect meanwhile becoming increasingly active. With the full growth of 

 the wings it acquires such powers of flight that it readily flies from vine to vine, and 

 thus spreads itself in all directions. It continues its mischievous work until late in the 

 season, when it seeks shelter for the winter." 



A species of this insect also attacks the Virginia Creeper, and in a dry season, 

 which seems most favourable for its development, we have known it to completely 

 destroy the foliage of the creepers on a building, and render them leafless before the close 

 of summer. When disturbed the insects hopped in myriads from leaf to leaf, making a 

 sound like the pattering of fine rain. 



Remedies. — When these insects attack the vines in a glass grapery, it is not very 

 difficult to deal successfully with them. First, carefully close the ventilators and any 

 other openings in the house, and then fumigate thoroughly by burning Persian Insect 

 Powder (Pyrethrum) beneath the vines. This has been found by experiment to be pre- 

 fectly effective. Tobacco may be used instead of insect powder, but the latter is not 

 reliable. After the operation all fallen leaves, etc., should be carefully removed and 

 burnt. 



Oat-of-doors it is by no means so easy to deal with this pest. Fumigation is almost 

 impossible, as the smoke cannot very well be kept long enough about the vines to destroy 

 the insect. On a calm still day, however, it would be worth trying. It should be done 

 several times at intervals of a few days, and if possible, before the insects have obtained 

 their wings and are able to fly away from the smoke. Syringing with strong soap-suds, 

 tobacco-water, hellebore mixed in water, etc., and dusting with lime or powdered sulphur, 

 have all been recommended, and are remedies worth trying. In all cases it is important 

 to keep the ground clean beneath the vines and leave no rubbish for the protection of 

 the hibernating insects. 



Mr. Fletcher, in his Report for last year, says that the remedy " which gives the 

 most promise of success is a weak kerosene emulsion in the proportion of one of kerosene 

 to thirty of water, to be applied at the time when the young bugs have first hatched. 

 Mr. John Lowe, the Secretary of the Department of Agriculture at Ottawa, tells me 

 that he has never failed to drive these insects off his grape-vines by simply applying 

 sulphur, which, when liberally applied to the vines, gives off on warm days a perceptible 

 odour of sulphurous acid gas which keeps the insects away." 



Dr. Lintner, in his second Report as State Entomologist for New York, mentions 

 that the vapour from tobacco juice has been very successfully employed in France as 

 a remedy for the grape-vine " thrips " and other small insects that infest plant-houses. 

 He quotes the experience of one who has tested it, and who says : " Ever since I adopted 

 it, it has been absolutely impossible to find a thrips in my houses ; and other insects 

 .have likewise disappeared." The mode of employing the remedy is thus described : — 



5 (EN.) 



