HEMIPTERA 



73 



(a) Winged and wingless individuals. 



(b) Big and little individuals. Those of all ages live 

 together gregariously. 



(c) Old ones in the act of giving birth to young. 



(d) Feeding individuals: poke one and make it with- 

 draw its beak from the plant. 



(e) Restless individuals, that in walking about get 

 kicked at by the others in passing. 



Fig. 27. — Aphids; winged and wingless forms of the same species. 



3. Try out a contact insecticide, like nicotine sulfate, 

 with a colony of greenhouse aphids (see p. 146). Potted 

 plants in the window garden will often furnish aphids 

 enough for this. The "dope" may be sprayed on with 

 an atomizer, or a colony on a slender shoot may be 

 dipped in a dilute solution. Note the result next day. 



B. The Study of Preserved Materials. 



a. The Adult 

 With a specimen of a squash bug or any similar bug in 



