INJURIOUS AND BENEFICIAL INSECTS 



4S 



88 Lace-winged flies (Chrysopa species). The delicate green, 

 gauzj winged adults are beautiful creatures. The voracious, 

 active larvae are veritable aphis lions, and may be seen in con- 



FiG. 80 Lace-winged fly Chrysopa oculata Say: a eggs; & full-grown larva; c foot of same; 

 dsame dpvourlng a Psylla; e cocoon; /adult insect; g head of same; h adult, natural size (reduced 

 after Marlatt, U. S. dep't agr., div. ent., circ. 7, 2d s.) 



siderable numbers on trees infested with aphids. The eggs, 

 curiously placed on the end of a slender stalk, always excite admir- 

 ation in the beholder. 



89 Spined soldier bug (Podisus spinosus). Represents a 

 number of species which prey on other insects. 

 This one feeds on a number of common pests, 

 such as the potato beetle, elm leaf beetle and 

 asparagus beetle grubs. One is frequently 

 seen with a grub of the elm leaf beetle or 

 asparagus beetle on its extended beak. 

 90 Pimpla (Pimpla conquisitor). 

 This species is one of the most valuable of the hymenopterous 

 parasites, and represents a large clasis of parasites which render 

 good service in keeping many pests under control. It was reared 



Fig. 81 Spined soldier 

 bug: a beak or proboscis 

 enlarged; b insect with 

 one wing extended 



