PHYLUM ARTHROPODA 



367 



females of other mining 

 bees, e.g. Halictus, band 

 together and use a single 

 main burrow from which 

 the individual channels 

 branch off (Fig. 309, A). 

 These bees therefore have 

 a tendency toward com- 

 munity life. The bumble- 

 bees, Bombus, live in 

 colonies during the sum- 

 mer, but these colonies 

 are temporary, since all 

 members but the young 

 queens perish in the 



. FIG. 308. Order HYMENOPTERA. Ich- 



nn. Anc :mally t ; neu mon-fly, Thalessa lunator, laying eggs 

 (oviposition). (From Sedgwick's Zoology, 

 after Riley.) 



honey-bees, as we have 



seen, are banded together 



in permanent colonies and have a very complex social life. 

 The solitary wasps (EUMENID^E) are miners, carpenters, or 



masons, i.e. they dig tunnels in the earth, excavate cavities 



in wood, or build mud-nests. Like the solitary bees., the Eu- 



menidae provision their nests, 

 lay their eggs, and then fly 

 away, leaving their young to 

 shift for themselves. 



Many of the digger-wasps 

 belong to the family SPHE- 

 GID.E. The mud-daubers 

 are common species. They 

 attach their mud-nests to the 

 ceilings of buildings or to the 



FIG. 309. Diagrams of nest burrows 

 of short-tongued mining bees. A, nest of 

 Halictus. B, nest of Andrena. (From 

 Hegner, after Kellogg.) 



lower surface of stones, and 

 provision them with spiders. 

 The digger-wasps of the West 



