66 NEW YORK STATE MUSEUM 



along the midvein and in the vicinity of the other veins. These 

 are, in the ordinary course of affairs, frequently followed by 

 severe injury and many of the whitish or yellowish white, jump- 

 ing adults. Badly infested foliage frequently has the under 

 surface thickly specked with the white membranous cast skins 

 of the young. This leaf hopper was exceedingly abundant and 

 somewhat injurious to the foliage of young apple trees at Ghent, 

 N. Y., in October 1909. This unusual attack was not unpre- 

 cedented, since the late Dr C. V. Riley had earlier recorded this 

 species as abundant on apple foliage. It has also been taken 

 upon the leaves of plum, cultivated cherry, currant, grape, elm 

 and soft maple. 



Dr T. W. Harris, the first American to write of this species, 

 thought that the insect might winter in the perfect stage con- 

 cealed under fallen leaves and rubbish. This supposition has 

 been repeated from time to time with no additional information 

 respecting the life history of this species. Last winter and early 

 in the spring the eggs of this species were found just under the 

 bark of the new growth of rose bushes and the young issuing 

 therefrom reared to maturity. 



Description. The full-grown or perfect leaf hopper is about 

 one-eighth of an inch long, yellowish white, the wings usually 

 being whitish and semitransparent. The eyes, claws and ovi- 

 positor are brown. 



The young present a general resem.blance to the adult. They 

 are distinctly smaller, especially when newly hatched, with only 

 rudimentary wing pads and a very light green. They fre- 

 quently harmonize so closely with the color of the under side 

 of the leaf that it is difficult to recognize them. 



The egg is semitransparent and has a length of .7 mm and 

 a diameter of .2 mm. It is narrowly oval, the anterior extremity 

 being broadly rounded, while near the posterior third there is 

 a slight curve, the posterior extremity being narrowly rounded. 



The eggs are deposited singly just under the new bark. Their 

 location is indicated by an almost imperceptible, oval elevation 

 in the bark about i mm long and presenting a slight greenish 

 or yellowish discoloration occasionally accompanied by in- 

 creased transparency due to the egg beneath. There is at one 

 end of the elevation a very slight scar made at the time the 

 egg was deposited. This wound is quite different from the 

 elongate lenticels seen upon the wood. It is comparatively easy 



