38 i NATURAL HISTORY 



the usual mamlibulate plan, with five-jointed maxillary and four-jointed labial palpi, but the 

 labrum is very small and concealed. The general form of the body is somewhat cylindrical, and 

 it is enclosed in a veiy hard skin ; the abdomen, which is attached to the thorax by a short 

 petiole, shows externally three or four segments, of which the second is very large, and its lower 

 surface is generally hollowed out so as to enable the insect to form itself into a sort of ball after the 

 fashion of a hedgehog or woodlouse. The hinder margin of the last segment is usually toothed, 

 and the number of teeth is often useful in distinguishing the species. Besides these apparent 

 segments, however, the abdomen possesses two or three more, which form a sort of telescopic 

 tube, capable of being retracted within the abdomen, and at the extremity of these is a sting, 

 which, although minute, is able to inflict painful wounds. The venation of the wings is much 

 more simple than in any of the preceding families ; there is only one submarginal cell, and 

 even this is not closed. 



These insects are of small size, comparatively few of them exceeding half an inch in length. 

 The number of known species is probably between 400 and 500, and they occur in most parts of 

 the world, but are decidedly more plentiful in Europe than elsewhere. All present a very strong- 

 family likeness, and their habits are similar throughout the family. About twenty-five British 

 species are recorded, and of these we may take one of the commonest, the Chrysis ir/nita, as the 

 type of the whole. This insect, the Common Gold Wasp, or Ruby -tail, measures from four to li\e 

 twelfths of an inch in length, and is of a deep metallic bluish green colour, except the upper 

 surface of the abdomen, which is bright red, with a beautiful golden gloss upon its sun 

 The whole surface is closely, and more or less coarsely punctured ; the thorax is spotted with 

 black ; and the apical margin of the abdomen shows four teeth, with a row of ten little pits just 

 in front of them. This beautiful little creature is to be seen almost everywhere during the 

 summer, flying in the hot sunshine, creeping about walls and palings, especially in gardens, and 

 poking its head into every small hole it meets with. This is the female insect, which, when thus 

 occupied, is engaged in looking out for the nest of some Bee or Wasp in which she can lay her 

 On finding an occupied burrow or nest undefended by the owner, the Chrysis immediately 

 makes its way in, and leaves an egg behind her. It appears that the larva hatched from this 



loes not make its appearance until the Bee- or Wasp-larva is nearly full-fed ; it then attacks 

 and soon devours the latter. The full-grown larva of the Chrysis spins a little cocoon within which 

 it passes to the pupa state. Occasionally, when the little Gold Wasp is inspecting the nest 

 of an absent Bee or Wasp, the rightful owner returns, and not unnaturally manifests a good 

 deal of indignation at the intrusion. In such cases the Bee will seize the Chrysis with her man- 

 dibles, and unceremoniously throw it out of the nest, but the sting of the Bee or Wasp is quite 

 powerless against the hard plate armour in -which the parasite is encased. The latter, how. 

 is not easily discouraged ; she will make her way back again and again to the nest from which 

 she has been ejected ; and when a Bee, losing its temper at the pertinacity of its little enemy, has 

 bitten off the wings of a Chrysis, the latter has been seen to unroll itself and crawl up once 

 more to the nest. The finest European species of the family is named Slilbum splendidum. It 

 measures from half to seven-twelfths of an inch long, and is usually of a fine blue or emerald 

 given colour, but has the abdomen sometimes golden red. This insect occurs in Southern Europe 

 and throughout Africa and Southern Asia. 



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