72 N.S. ENTOMOLOGICAL SOCIETY. 



turn and with a pale or bluish blotch just before the apex, which, in some cases, extends 

 forward to the margin of the pronotum. Elytra a golden green, the coloration stopping 

 a little before the cross-veins, the tips slightly smoky. Abdomen yellowish above and be- 

 low, the last ventral segment of the female having two deep oblique notches or slits 

 on the posterior margin inclosing a stout blunt tooth between them. Legs greenish 

 yellow, tarsi blue." 



LIFE HISTORY. 



The eggs of Empoa rosae Linn, begin to hatch soon after growth starts in the spring 

 but these insects have already developed as far as their fourth and fifth instar before 

 the nymphs of Empoasca unicolor Gill, begin to appear. According to records taken in 

 1917 the nymphal stage is of about six weeks duration, after which copulation takes 

 place and the eggs are deposited beneath the bark of the twigs, there being only one 

 brood per season. The details of fifteen individuals reared from the eggs to the adult 

 stage are shown in the accompanying table. 



CONTROL. 



We have never seen this insect present in sufficient numbers to warrant a recom- 

 mendation of special treatment. Contact sprays are expensive and it is necessary to be 

 sure that the return will exceed the outlay before such recommendation should be given 

 Since this species does not cause any severe curling of the foliage it is a comparatively' 

 easy pest to control by means of a spray of nicotine sulphate or fish oil soap; coming as 

 it does so late in the season, when spraying for other sucking insects is completed, this 

 would probably never be done. While conducting experiments in orchards during the 

 past season, it was noticed that a very finely powdered tobacco dust destroyed large 

 numbers of the nymphs. 



