Hymenoptera 277 



often exceedingly large, hiding to a great extent the three succeeding 

 segments which can be observed. The first segment of the feelers is 

 short and stout, the second long ; these two form the scape, and the 

 remaining (eight to eleven) segments attached at a marked angle to 

 these, make up the flagellum. Ants live in large communities, 

 consisting of many males and females and immense numbers of 

 w^ingless, undeveloped females or " workers." The workers build the 

 nests, and collect food which consists largely of honey ; this can be 

 disgorged by them to feed the larvse and their comrades remaining in 

 the nest (fig. 153 ; see also below pp. 335-6). Ants are exceedingly 

 numerous in tropical countries, but become much scarcer in species 

 in cooler regions ; they are however distributed throughout the world 

 (l6l-S)- . 



Mutillidae. — The MutUUda: are a comparatively small family 

 sometimes known as " Solitary Ants." They resemble the Formicidx 

 in the deep constriction between the second and third abdominal 

 segments. They do not live in communities and there are no 

 " workers " ; the males are winged and the females wingless. In 

 the male the pronotum reaches backwards on either side to the base 

 of the fore-wing, and the last visible abdominal segment has one or 

 more spines or blunt teeth. The females have stout digging legs 

 with spiny shins. In both sexes the haunches of the middle pair 

 are close together. The Mutiilid^ are mostly black and red or 

 yellow in colour ; many species are adorned with bands of white 

 hairs. Their larvs live as parasites in bees' nests. The family is 

 fairly abundant in the tropics of both hemispheres, but becomes 

 scarce in cooler regions ; only two species inhabit our islands (162). 



Thynnidae. — The ThynniJj; are a small family agreeing with the 

 Mutillida; in the sex-distinction — the winged males and wingless 

 females — but distinguished by the absence of a constriction between 

 the second and third abdominal segments. The male pronotum 

 reaches back to the forewing-bases as in the Mutillidz and there is 

 often a spine on the last abdominal tergite. The range of this 

 family is like that of the last, but only a single species {^Meihoca 

 ichneumonoidds) reaches England (162). 



Scoliidae. — The ScoIHd^ are a large family of Digging- Wasps 

 which resemble the Mutillids in the constricted stalk of the hind- 

 body, but are distinguished by the widely separated middle haunches ; 

 both sexes, moreover, are winged. The feelers of the male are long 

 and threadlike, those of the female shorter and curved. The sides 

 of the pronotum reach back to the bases of the fore-wings ; the first 

 abdominal segment is as long as, or shorter than the mesonotum. 

 The legs are short and stout, usually clothed with stiff hairs and 

 spines. The fore-wing has always a radial and at least two cubital 

 cells, but the apical third of the wing is oi'ten without any neuration. 

 The hind-body, especially in the female, is very long and heavy; in 

 the male it is more slender and the last segment bears one or more 

 spines. The Scoliids vary in size ; some are giants among the 



