112 



NATURAL HISTORY OF INSECTS. 



CHAPTER XVI. 



r FAMILIES OF HEMIPTERA. (True Bugs.) 

 SUB-ORDER I. HOMOPTERA. (Similar-winged Bugs.) 



PLANT-LICE (Aphidse). These insects are usually provided 

 'with four transparent wings, but many of them are wingless; 

 the feet are two-jointed; the antennae are from three to seven- 

 jointed, and are never terminated by two bristles; the abdo- 



Fig. 291. 



men is frequently provided with two tubercles, or long tubes, 

 near the posterior end, and the beak appears to arise from 

 the breast. These insects are usually of a small size; they 



Fig. 292. 



subsist on the juices of plants, and are found upon the roots, 

 stems, and leaves; a few species form galls. They are gene- 

 rally gregarious in their habits, and the early broods of many 



