HYMENOPTERA PETIOLATA. 



767 



During the first half of the summer, only workers appear, but later males 

 and perfect females make their appearance, the former perhaps from the 

 parthenogenetic eggs of the later brood of workers ; all these kinds are 

 winged, but the workers are smaller than the males or females. The sexes 

 pair whilst flying, and soon afterwards the males die. The youngest larvae 

 are fed on nectar from plants, but this diet is soon replaced by one of 

 insect flesh, the female wasp catching her insect prey on the wing. This 

 is slightly masticated by the mandibles and then offered to the progeny. 



Of the eight British species, all of them belonging to the genus Vespa, 

 V. germanica, V. rufa and F. vulgaris make their nests underground, F. 

 arborea, V. sylvestris and F. norvegica in trees ; F. crabro, the Hornet, in 

 some such retreat as the hollow of a tree, whilst F. austriaca lives in the 

 nests of other species. The hornet does not extend north of the 

 Midlands. Polistes is the largest genus. 



Fam. 19. Masaridae (Fig. 499). Claws toothed ; fore-wings with two sub- 

 marginal cells the last two families 

 have four ; antennae clubbed. A 

 small family of few and rare forms. 

 Masaris, Ceramius and others are 

 Mediterranean, Paragia Australian 

 and Trimeria S. American. They 

 seem mostly to construct earthen 

 cells either underground or on 

 twigs. 



The following three families are 

 often united under the name Fossores 

 or Digging Wasps. The anterior 

 wing is not plicate in repose ; the 

 hairs are not plumose ; the basal 

 segments of the abdomen have dor- 

 sally no prominences ; there is no 

 worker caste. 



Fam. 20. Scoliidae. The sides of 

 the pronotum reach to the tegulae 

 at the base of the wings ; abdomen 

 with a chink between the first two 

 segments on the ventral side. This 

 family includes five sub-families 

 consisting chiefly of tropical forms. 

 They neither construct cells nor 

 burrows, but as a rule lay their eggs on 

 some insect larva which they have 

 previously paralysed with their sting, and which serves their larvae for food. 

 Sub-fam. 1. Mutillinae. No wings or ocelli in the females, in 

 which also the parts of the thorax are closely fused ; the males are 

 winged, with ocelli and parts of the thorax distinct ; two spurs on 

 second pair of tibiae ; two or three sub-marginal cells on fore- 

 wing. 



This sub-family is rather ant-like and the members are known as 

 " Solitary Ants "; the hairy coating and the absence of a node at the 

 base of the abdomen however readily distinguish them from true 

 ants. Many of them are brightly coloured, black, red, yellow and 

 white occurring, and some stridulate. The larvae live at the expense 



FIG. 499. Masaris vespiformis. A male ; 

 B female. Egypt (after Schaum). 



