192 OTHER MEMBERS OF THE CLASS — INSECTA 



Fig. 137. — Yellow jacket 

 wasp. 



comb of many cells, side by side, without any covering (Fig. 



135), and suspended from some object by a small stem 



or peduncle. These wasps are black and ringed with 



yellow or are brownish (Fig. 136). The familiar yellow 

 jackets (Fig. 137) and hornets build 

 nests composed of several layers of 

 comb surrounded by a gray papeiy 

 material (Fig. 138). The nestg of 

 the yellow jackets are usually built 

 in the ground. The colonies of social 

 wasps consist of males, females, and 

 workers. Every colony is broken up 

 in the autumn, only the females sur- 

 viving. 



The familiar nests of the mud- 

 dauber wasps (Fig. 139) consist of 



several layers of long cells made of mud, lying side by side. 



They are built in the attics of houses or in barns or other 



outbuildings. The 



adults may be seen 



about puddles of 



water, gathering 



mud to build their 



nests. An egg is laid 



in each cell which is 



then filled with liv- 

 ing but paralyzed 



spiders to furnish 



food for the young 



^^gpg_ Fig. 138. — Nestof Vespa. 



Not all wasps are social. Some live alone, hence are 

 called solitary. They build their nests in a variety of 



