138 CHEREY. LEAYES — CHEEKY APHIDItJS. 



gin of fore wings blackish, liength about 0.07. Hatched from an undescribed aphis 

 infesting the base of the leaves of the Balm of Gilead {Populus candicans). 



But without dwelling longer upon this interesting group of in- 

 sects which render us such important services, we close with a 

 notice of a species which destroys the aphis of the garden cherry, 

 and which differs from all the foregoing in its residence when in 

 the pupa state. As if fearful that the beak and feet of the dead 

 aphis would not hold its swoolen body securely to the smooth' 

 surface of the cherry leaf, (he worm of this species when ready to 

 entfr its pupa state perforates the abdomen of the aphis upon its 

 under side, probably as soon as its life is extinct, and spins a 

 cocoon for itself between the leaf and the body of the aphis, the 

 leaf forming the floor of the room for its residence, the abdomen 

 of the aphis forming its roof, and a gray paper-like membrane 

 which it weaves constituting the sides and attaching the body of 

 the aphis securely to the leaf. The walls of its domicil are so 

 thin that the iaclosed pupa can sometimes be seen faintly through 

 them, of a bright yellow color. 



The Cheery Aphidius (Trioxys Cerasaphis) is black with its palpi or feelers and 

 legs pile yellowish brown; antenQze almost as long as the body, 18-jointed, the third 

 and fullDwing joints equal, cylindric, thrice as long as broad, the last elongated 

 ovate; abdomen elliptic, rather narrower and shorter than ti)e thorax, scarcely pedi- 

 celled at its base, shining, tinged with brownish; wings pellucid, stigma smoky white. 

 Length 0.07. 



