THE AiAIERICAN ENTOMOLOGIST. 



123 



liaiidled witliout fear; but, nnfortnnately, in 

 order to distiuguisli the sex, we are generally 

 obliged to catch the little animal lirst; for, as a 

 general rule, which, however, admits of ex- 

 ceptions, the male wasp is scarcely distinguish- 

 able from the female, except by having, with a 

 very few exceptions, thirteen-jointed (not 

 twelve-jointed) antennas, and a seven-jointed 

 (not six-jointed) abdomen. So that, practi- 

 cally, this criterion is not of much value ; and 

 to ascertain whether a wasp can sting, we must 

 first take it in our hands, and give it a fair 

 chance to do so if it is able. It is remarkable 

 that the very same distinctions between the 

 sexes, as those which have been detailed above 

 as generally found among the wasps, prevail 

 almost universally among the ants and bees. 



The Digger Wasps and the True Wasps. 



The wasps are divisible into two grand groups, 

 the lirst of which is two or three times as 

 numerous in species as the second; namely, 

 _flr>it, the Digger Wasps, or Fossorial AVasps 

 {Fvssores), and secoiuU//, the True Wasps, or 

 wasps with folded wings (^Diplopteinj(ja.) There 

 is no one obvious universal cliaracter by which, 

 without a solitary exception, these two groups 

 are distinguishable; but, with the exceptions 

 lierealter to be noted, they may be distinguished 

 by the following easily-observed criterions: 



1. None of the Digger AVasps have their 

 wings folded up in repose. All the True Wasps, 

 on the contrar,v — with the single exception of 

 an exotic genus (C'e/Y/w/((.,), which has not as 

 yet been found in North America, and to a 

 partial extent, of another exotic genus {Mu- 

 san's), found in this country exclusively in the 

 Rocky Mountain region— Iiave their wings folded 

 in repose, in the singular manner shown in 

 Figure no, wliere c represents the upper surface 

 of the hind wing, with its front edge hooked 

 [t'ig. oi;.] on as usual to the 



C'/.--;:^:- .Cr^^^^^^***===5i«a^ front wing; a, all 

 . ■-;:■■■■.-■. -^-^-r—^^^ ^a jjj^t [<- visible from 



above of the upper surface of the front 

 wing, and b, the lower surface of the front 

 wing doubled over upon itself. Westwood 

 has remarked that this peculiar folding of 

 Die wings '• is so constant and character- 

 istic, that we look in vain tln-oughout the 

 whole order {Hymenoptcra) for any other in- 

 stance." But, Westwood forgot that, in a 

 single genus of Chah-is Flies (Leucospis), tlie 

 wings .are folded in precisely the same manner, 

 as had been partly stated by himself in a 



previous page of the same volume.* With this 

 exception, his remark appears to be correct. 



2. The eyes of the Digger Wasps are generally 

 oval, rarely round, as in the female of one 

 genus (J/M<(7/a); or kidney-shaped, as in botli 

 sexes of two genera {Tnjpoxylon and Scolio), 

 and in the males, but not in the females, of two 

 other genera {2IutiUa and Jfi/ziiie). On the 

 contrary, all the True Wasps, with the single 

 exception of one Australian genils {Parapui). 

 liave their eyes kidney-shaped, the hollow, or 

 scooped-out part of the kidney facing tlie base 

 of the anteinia. 



3. Most of the Digger Wasj^s, especially in 

 the female sex, have their legs thickly set with 

 long stiff bristles or slender thorns, the use of 

 which we shall presently see. Certain excep- 

 tions which occur will be noticed hereafter, and 

 the reason thereof explained. The True Wasps, 

 on the other hand, always have tlieir legs free 

 from bristles or tliorns, although the joints of 

 their paws (farsi) are often prolonged on each 

 side in an acute angle at their tips, so as at lirst 

 sight to somewhat resemble small thorns. 



Having thus enabled the reader to tell the 

 dilTerence between a Digger Wasp and a True 

 AA^asp, we will take up each group in its turn 

 and exi)lain and illustrate its peculiar habits. 



The Digger Wasps. 

 Every one knows lliat Blow-flies or Meat-Hies 

 will deposit their eggs, which are commonly 

 called '■■ fly-blows, ■■ upon meat; and that these 

 eggs soon afterwai-ds hatch out into whitish 

 meat-feeding maggots, destined in the course of 

 a few weeks to reproduce the mother-Hy ; after 

 which the same old cycle of phenomena is re- 

 peated again and again. In the same manner. 

 the thousands of diiiereut species of Iiloths and 

 Butterflies, the larv:e of which feed upon tlic 

 leaves or the buds or the stems of diiferont 

 herbs, shrubs and trees, deposit their eggs in or 

 on, or at all events close to, the substance upon 

 which their future larva} are destined to subsist. 

 And to these might be added a host of other 

 insects, such as the various Clothes-moths and 

 Fur-moths, the Cheese-fly, the different Bacon- 

 beetles and Cheese-beetles, the Apple-worm 

 Moth, &c., &c., all of which have the same re- 

 markable habits in this respect. We call them 

 remarkable, because many of these insects can 

 not feed in the perfect state — in which ^tale 

 alone they are capable of laying eggs — upon tlic 

 substances that they lay their eggs on. For in- 

 stance, all the Butterflies and Moths feed in the 

 perfect state upon the nectar of flowers or otlier 



♦see West wood's Introduction, II, p. 23S, anil \>. li".4. 



