under surface of the tender leaves. These eggs hatch in June, and the 

 young larvae, which resemble the adult except in size and in having no 

 wings, suck the juices from the leaves, generally remaining on the under- 

 side. During their growth tbey molt their skins several times, and these 

 may often be seen on the leaves. After a time the larvae transform to 

 pupae with the rudiments of wings, and finally when they reach maturity 

 the wings appear fully developed. 



They are now able to fly from vine to vine or even from one vineyard 

 to another. Late in October they seek a shelter for the winter, where 

 they hibernate till the following spring. Leaf-hoppers are very active in 

 their movements, and hop from one leaf to another or run sideways, 

 often passing quickly from one side of a leaf to the other for protection 

 when disturbed. 



Nature of Their Attacks. 



Leaf-hoppers do not consume the substance of the leaves, but forcing 

 their tube-like mouth-parts through the epidermis or skin, suck the sap 

 from the interior. The leaves first indicate the presence of these insects 

 by becoming yellowish or brownish in small spots where the sap has been 

 exhausted. As the insects increase in size and take more sap, these 

 spots grow larger and the whole leaf appears as though scorched, turning 

 brown and even falling off in cases where the hoppers are very abundant. 

 The result is that as the leaves are injured, the growth of the stem is 

 checked, the fruit is stunted or fails to ripen, and if the ravages of these 

 insects are not prevented, the vines become entirely ruined in a few 

 years. 



Some varieties of grapes are especially liable to suffer from the leaf- 

 hoppers, as the Delaware, Clinton, and in general all varieties having 

 thin leaves. The abundance of these insects from year to year seems to 

 depend in a large degree upon the severity of the winter and their ability 

 to obtain protected places for shelter. 



Remedies. 



The remedies should vary according to the location of the vines. If 

 they are in graperies, smoking them with tobacco, taking care to prevent 

 the escape of the smoke, has been tried with good results. Similar treat- 

 ment with Persian Insect Powder poured upon burning coals carried 

 under the vines is also successful. Syringing with strong tobacco-water 

 or soapsuds, dusting with lime, sulphur and lime, hellebore and cayenne 

 pepper have all been recommended but have not yet been tested at this 

 station. 



In vineyards, the treatment is more difficult as the adult insects can fly 

 away, and thus avoid the fumes of tobacco or insect powder. If fumi- 



