MUTUAL AID AND COMMUNAL LIFE AMONG ANIMALS 385 



a rather large irregular mass and puts 

 into the hole, and lays a few eggs on 

 the pollen mass. The young grubs or 

 larvae which soon hatch feed on the 

 pollen, grow, pupate, and issue as 

 workers winged bees a little smaller 

 than the queen. These workers bring 

 more pollen, enlarge the nest, and make 

 irregular cells in the pollen mass, in each 

 of which the queen lays an egg. She 

 gathers no more pollen, does no mo r e 

 work except that of egg-laying. From 

 these new eggs are produced more 

 workers, and so on until the com- 

 munity may come to be pretty large. 

 Later in the summer males and females 

 are produced and mate. With the ap- 

 proach of winter all the workers and 

 males die, leaving only the fertilized 

 females, the queens, to live through 

 the winter and found new communities 

 in the spring. 



The social wasps as with the bees, 



Q 



b 



FIG. 238. Bumblebees: a, 

 Worker; b, queen or fer- 

 tile female. 



\ 



^ 



FIG. 239 The yellow jacket, Vespa, a social 

 \\asp: a. Worker; b, queen. 



there are many more kinds 

 of solitary wasps than social 

 ones show a communal life 

 like that of the bumblebees. 

 The only yellow jackets and 

 hornets that live through 

 the winter are fertilized 

 females or queens. When 

 spring comes each queen 

 builds a small nest sus- 

 pended from a tree branch, 

 or in a hole in the ground, 

 which consists of a small 

 comb inclosed in a covering 

 or envelope open at the 

 lower end. The nest is 

 composed of "wasp paper," 

 made by chewing bits of 



