250 Agricultural Experiment Station, Ithaca, N. Y. 



danger of injury- to the trees from the diluted emulsion. All 

 dwarfs and young trees of all kinds may be sprayed with a knap- 

 sack sprayer. 



The best time to sprny is early in the spring just after the leaves 

 have expanded. In 1S!)2, about May fifteenth, was the best time. 

 Then the fii-st brood of nymphs had all emerged and were exposed 

 in the axils. It was this first brood which did the most damage 

 in 1891. Therefore, it is very important that the insect should 

 be checked early in the season. Fruit-growers should examine 

 their orchai'ds when the leaves are expanding in the spring, and 

 if the nymphs are numerous no time should be lost in spraying 

 the trees with emulsion. A second or even a third spraying could 

 be profitably applied if the attack were serious, and especially if 

 but little rain had fallen to wash off the honey-dew. The destruc- 

 tion of the nymphs is practicable during a period of two weeks 

 about May fifteenth. If the spraying is thoroughly done at this 

 time, (the pest will be so completely checked as to necessitate but 

 little, if jmy, further attention during the season. Most of the 

 damage is usually done before June fifteenth, but spraying after 

 this date will decrease the nmnber from which the hibernating 

 forms are produced; and thus the orchard may be saved from a 

 sevei'e attack the following year. 



The summer adults were not numerous enough this year to 



thorongliJy test the effect of spraying upon them. It seems from 



the exjjeriments made last year by fruit-growers that it is hardly 



practicable to kill the adults by spraying. A few may be 



destroyed by coming in contact with the emulsion when they 



return to the tree. 



Technical Descriptions. 



Full grown nymph. — Length, 1.4 min.; width, 1.15 mm. Oval 

 in outline, and much flattened, being only about one-fifth as thick 

 as long. General color light yellowish brow^n often tinged with 

 crimson, and distinctly marked with blackish. The distal end of 

 the antennjae, of the beak, and of the tarsi are black. The large 

 wing pads, the whole doirsal aspect of the head except a large 

 mesal stripe, and the caudal half of the abdomen both on the dor- 



