ANTS, BEES, WASPS, AND THEIR KINDRED 1 13 



good reason for thinking that the grubs of at least 

 some species are true parasites which destroy the off- 

 spring of the bee or wasp. A common and very 

 beautiful member of this family is Chvysis ignita, whose 

 females may often be observed searching the crevices 

 of brickwork for the nests of solitary wasps. 



Nearly all our British fossors, or digger-wasps, are 

 comprised in the two families Pompilida and Sphegidcz. 

 Of the former we have about thirty species, of the 

 latter upwards of ninety. They get their popular 

 name from the fact that many kinds excavate burrows 

 in the soil, though not a few drive tunnels in decayed 

 wood, or in the stems of bramble and other plants. 

 Mr. Latter has pointed out that whereas Pompilids, 

 when digging, use their feet and the coxal joints of 

 the legs as tools, Sphegids employ only their powerful 

 jaws. 1 The far end of the burrow or nest is stored 

 with some kind of animal food, upon or near to which 

 an egg is laid. The Pompilids generally provision 

 their nests with spiders ; but the Sphegids commonly 

 store caterpillars, though some use beetles, two-winged 

 flies, aphides, etc., for the purpose. Usually each 

 species selects one particular kind of prey, which, 

 however, it does not actually kill, but paralyzes by 

 skilfully stinging one or more of the chief ganglia or 

 nerve-centres. In this way two ends are served : the 

 victim is unable to struggle while it is being conveyed 

 to the burrow, or to escape when it has been deposited 

 therein ; yet it remains untainted until it is required as 

 food by the wasp-grub. Our largest Sphegid wasp is 

 Ammophila sabulosa, a black and red species, with a 

 remarkably long "waist." It frequents such places as 

 gravel-pits, or dry patches of bare soil on commons ; 



1 ' ' Bees and Wasps. ' ' 



