SOCIAL WASPS VESPIDAE 



79 



closed. The food supplied is of a varied nature according to 

 the species, being either animal or vegetable, or both. 



Although the nests of the social wasps are very elaborate con- 

 structions, yet they serve the purposes of the Insects for only a 

 single season. This is certainly the case in our own country. 

 Here each nest is commenced by a single female or queen ; she 

 at first performs unaided all the duties for the inauguration of 



Fig, 31.— Section of the 

 subterranean nest of the 

 common wasp, Vespa 

 germanica, in position. 

 (After Janet.) a, One 

 of the chambers of an 

 ant's nest, Lasiusflmus, 

 placed ab9ve the wasps' 

 nest ; b, root to which 

 the lirst attachment of 

 the nest was made ; c, 

 secondary attachments ; 

 d, the first-made attach- 

 ment ; t", a Hint within 

 the envelopes of the 

 nest ; /the chief suspen- 

 sory pillar of tlie second 

 layer of comb ; i/, lateral 

 galleries ; h, one of the 

 secondary pillars of 

 suspension between two 

 layers of comb ; i, the 

 layers of wasp - paper 

 forming the envelope of 

 nest ; y, vacant space 

 round the nest ; k, tiints 

 that fell to the bottom 

 during the work of ex- 

 cavation ; I, numerous 

 larvae of a fiy, Pegomyia 

 inanis{l) placed vertically in ground beneath the nest ; m?- to 711', the layers of comb, 

 in m^ the cells are indicated , in m* (above the main figure) the arrangement of the 

 three cells forming the commencement of the new layer ot comb, m', is shown ; n, 

 gallery of access from surface ; 0, burrow of a mole ; jj, interval of 90 mm. between top 

 of nest and surface ; q, height of tne nest, 163 mm. 



the colony ; she lays the foundation of the cells, deposits the 

 eggs in them, feeds the young, and thus rears a brood of workers 

 that at once assist her, and for the future relieve her of a con- 

 siderable portion of her former occupations ; the nest is by them 

 added to and increased, till the cold weather of the autumn is at 

 hand ; at this time many males and females are produced ; the 

 cold weather either destroys the inhabitants of the nest, or re- 

 duces their vitality so that it is impossible for them to pursue 

 successfully the avocations necessary for their subsistence, and 



