490 



ARTHROPOD A. 



FIG. 525. Cicada septendecim* seventeen-year locust. (From Riley.) a, pupa; b, 

 case from which the imago, c, has escaped; d, twig bored for oviposition. 



pupa 



FIG. 526. Cicada orni. (From Schmarda.) 



or JASSHXE, contain some injurious forms, Erythronura vitis* damaging 

 the grape, while the true hoppers, MEMBRACID.E (fig. 527), are scarcely less 

 ^ injurious. None of these, however, are such serious 



pests as the plant lice and scale insects. In the 

 COCCID.E, or scale insects, the wingless female dies 

 after laying the eggs and covers them with her dead 

 scale-like body. Here belong the cochineal insects, 

 Coccus cacti,* the dried bodies of which furnish the 

 pigment carmine, and the lac insects, Coccus lacca, 

 as well as a host of injurious forms, like the orange 

 scale, Aspidotus aurantii* and the worse San Jose 

 scale, A. pernieiosus* which has recently been spread 

 throughout the country. The APHID^E, or plant lice, 

 are soft-skinned and with their honey-containing 

 excrement form a substratum for the growth of 



FIG. "wt.-Ceresa buba- in J urious fun gi- The y reproduce largely by parthe- 

 lus* buffalo leaf hop- nogenesis, a reason for their rapid multiplication ; 

 Marlatt.) . 



