252 MAINE AGRICULTURAL EXPERIMENT STATION. IQT2. 



INSECT ENEMIES OF THE WOOLLY APHID. 



So far as the natural enemies of this pest are concerned its 

 residence in the elm leaf curl is a vulnerable period strongly sub- 

 ject to attack. Very abundant in Maine working on the aphides 

 while in the elm leaf curl are a predaceous capsid, (Campto- 

 brochis nitens), flocculent larvae of a Coccinellid and syrphus 

 maggots. So numerous are all these insects in certain years 

 that it has sometimes been difficult for me to secure enough of 

 this aphid for experimental purposes, a search through many 

 emptied leaf curls being necessary before aphides could be 

 found. 



In other parts of the country also this aphid is preyed upon 

 while in the elm leaf curl and frequently the only living arrivals 

 in material sent me from other states has been the predaceous 

 insects within the leaf curl. 



Riley (1879) records as follows: "Among the more promi- 

 nent of the natural enemies of this species I have noticed, of 

 Coleoptera, Coccinella p-notata, Coccinella sanguined (munda) 

 Say, Hippodatnia convergens, and several species of Scymnus. 

 I also found feeding upon them the perfect beetle of Podabrus 

 modestus, and the Hemipterous Cyllocoris scutellatus Uhler, 

 and Capsus lincaris Beauv. A Lepidopterous inquiline, name- 

 ly, the larva of Semasia prunivora Walsh is also quite common 

 within the curled leaves, feeding both on the. lice and on the 

 substance of the leaf. A large green Syrphus larva and several 

 Chrysopa larvae also prey upon them." 



While on the apples the woolly aphid is subject to the attacks 

 of a number of insect enemies, those recorded by Marlatt (1897) 

 including "the parasitic chalcis fly, Aphelinus mail Haldemann, 

 and the larva of a syrphus fly, Pipiza radicum Walsh and Riley, 

 and also the larva and adult of several species of lady birds, the 

 larvae of lace-wing flies, and spiders, etc. In the East a very 

 small brown species of ladybird, Scymnus cervicalis Muls., is 

 often present in some numbers, and the common nine-spotted 

 ladybird, Coccinella p-notata Hbst., is also an active enemy of 

 the woolly aphid. 



