BEES, WASPS, ANTS, ETC. 



535 



cells by removing the inner layers of the envelope, the portion removed being remasti- 

 cated and added to the outside. The nests ai-e suspended from the branches of shrubs 

 and trees, or from fences and roofs. Certain species build their nests in holes in the 

 ground. 



In eacli cell of the comb an egg is laid. Owing to the position of the comb, when 

 the larva hatches, it is suspended head downwards in its cell. This position they 

 retain while young by means of a glutinous secretion, and later by the enlarged 

 cephalic portion of the l;iody, which completely fills the open part of the cell. The larvae 

 receive constant attention from the females and workers, and are fed with nectar, the 

 juices of fruits and of animals, and with more solid food chewed fine by the adults 

 before feeding. On reaching full growth the larva spins a silken cocoon, the lower 

 end of which serves as a cap to the cell, and transforms to a pupa. After the adult 

 has issued, the cell is cleaned out and used again, as the whole period from the lay- 



... . - -V~-\ 



Fjg. 661. —Larva, pupa, comb, and adult of (-'tspa cra6o, lioruct. 



ing of the egg to the emerging of the adult is about one month at the north, so that 

 the comb made early in the season serves for several successive broods. The males 

 and queens are not developed until towards autumn. At this time larger cells are 

 made for the reception of the eggs which are to produce the sexual forms. 



Although the social wasps feed uiion nectar, honeydew, and the juices of fruits, 

 they are also carnivorous, destroying large numbers of other insects. 



Our common species of social wasps represent the two genera Polistes and J^e.ipr/. 

 To the genus I-'olistefi belong the common long-bodied black wasps with folded wings 

 and sub-pedunculate abdomens. They frequently enter <lwellings in the autumn, seek- 

 ing places for hibernation. The nest of PoUfites consists of a single comb without 

 envelope, and m.ay be found in almost any country barn. They are also attached to 

 bushes and to the lower surfaces of stones which are slightly raised from the ground. 

 In this country these nests are almost invariably horizontal, but European writers 

 figure the nests with vertical combs. 



