ORDER HYMENOPTERA : ANTS, BEES, WASPS, ETC. 227 



up honey and pollen. Honey is the nectar of flowers 

 regurgitated from the bee's crop after undergoing certain 

 changes there. The bumble-bees also live in communities 

 which, like those of social wasps, die off in the autumn and 

 are independently renewed in the spring by casual females 

 which have managed to survive winter. The gregarious 

 (non-social) bees make a common gallery, in which each 

 mother makes her own cells and fills them with a mixture of 

 honey and pollen before laying an egg in each and closing 

 it up. The solitary bees make nests of many kinds ; of bits 

 of dry wood in holes drilled in timber (carpenter-bees) ; of 

 pieces of leaf specially cut, and folded or gummed together 

 (leaf-cutting bees) ; of stones and specially made cement 

 (mason-bees) ; of resin ; of cotton ; and of wool. All kinds 

 of bees — solitary, gregarious, and social — are much liable to 

 the attacks of parasites. 



(b) Diploptera (SnrXovi = doubled ; vrepov = wing). This 

 section includes the Solitary wasps (which must not be con- 

 fused with the Fossorial wasps of the next section) and the 

 Social wasps. Wasps can be distinguished, in life, by the 

 fact that the front wings in repose are folded double, the 

 bend running longitudinally from the base to the tip of the 

 wing. The tarsi of the hind legs are not dilated, and there 

 are no feathered hairs on the body. Wasps, though they 

 may eat our fruit and jam, are chiefly carnivorous, and prey 

 largely upon Diptera. They should therefore be protected, 

 and the medical officer should never be weary in explaining 

 that wasps, however furiously they may appear to rage, do 

 not sting unless they are molested. The females of the 

 Solitary wasps {Eumenida) make cells of clay which they 

 fill with caterpillars for the expected larva to feed upon : the 

 egg is suspended from the roof (so as not to be injured by 

 the movements of the imprisoned caterpillars) before the 

 cell is sealed up. The Social wasps live in communities 

 consisting, to begin with, of a queen, and workers, which are 

 like her in everything but size and the condition of the repro- 

 ductive organs. The community is founded in the spring by 

 a female (queen) which has chanced to survive winter : she 

 merely begins the comb, lays an egg in each (unfinished) cell, 

 and rears a brood of workers : these complete and enlarge the 



