THE BUTTERFLY AND ITS ALLIES 31 



other insects, the gall-flies, or gall-wasps, and the plant- 

 eating Hymenoptera. 1 



The bees (Apidae 2 ) include both social species and others 

 which lead solitary lives. Of the latter, some dig their 

 nests in the ground ; others are masons, and build their 

 nests of mud ; others are carpenters, and make tunnels 

 through pithy plants, or even solid wood ; while still 

 others are leaf -cutters. These leaf-cutting bees carve 

 circular disks from rose leaves, out of which they make 

 cells for their young. 



Of the social bees, our native species belong to the 

 genus Bombus, the " bumble " bees. The bumblebees 

 build nests in the ground. 

 The queens only survive the 

 winter. In the spring each 

 queen chooses some mouse 

 nest or other ready-formed 

 cavity in a meadow, and 

 places within it a ball of 



, . , , FIG. 31. Bombus, the bumblebee. 



pollen. Upon this tood she Nat. size. Photo, by W.H. c.r. 

 lays eggs, which develop into 



worker bees. As soon as the workers are full grown they 

 begin the task of gathering food, and the queen then de- 

 votes all her energy to egg-laying. Later in the season 

 males and young queens also appear in the nest. The 

 old and young queens dwell together in harmony until 

 autumn, when all the members of the colony perish except- 

 ing the young queens, which pass the winter in some 

 sheltered spot and form new colonies in the spring. 



1 A key to the principal families of the Hymenoptera is given in the 

 Appendix to this Chapter, p. 42. 



2 From apis, bee. 



