PHYLUM ARTHROPODA 



3 6 3 



Some of the worst 

 pests are the locust 

 borer, Cyllene robinia, 

 the apple tree borer, 

 S a per da Candida, and 

 the sugar maple borer, 

 Plagionotus speciosus. 

 A common species, 

 Tetraopes tetraophthal- 

 mus, is found on milk- 

 weed. 



Suborder 6. Tri- 

 mera. (Ladybird 

 Beetles, Fig. 302.) — 

 The CocciNELLiD.E, 

 or ladybird beetles, 

 are predaceous, both 



CO 



Fig. 302. — Order Coleoptera. Novius cardv- 

 nalis, Australian ladybird beetle, feeding on the 

 fluted scale, Icerya purchasi. a, ladybird larvae 

 feeding on adult female and egg sac ; b, pupa ; 

 c, adult ladybird ; d, orange twig, showing scale 

 and ladybirds — natural size. (From Marlatt.) 



as larvae and adults, 

 feeding largely on plant-lice and scale-insects. They are conse- 

 quently beneficial since they help control these pests (see p. 347). 

 Suborder 7. Heteromera. (Darkling, Blister- and Oil- 

 Beetles, Fig. 303.) — The Heteromera contains the darkling 

 ground-beetles (TenebrioniDje), one of which, the meal-worm, 



Tenebrio molitor (Fig. 303) , 

 is quite common in mills 

 and grocery stores and is 

 used as food for cage 

 birds. This group also 

 includes the blister- and 

 oil-beetles (Meloid^e) ; 

 some of these when dried 

 and pulverized have a 

 Fig. 303. — Order Coleoptera. Meal- blistering effect when 

 worm, Tenebrio molitor. A, larva. B, pupa. a rjplied to the human 

 C, adult. (From the Cambridge Natural *y 

 History.) skin. 



