THE iJIERICAN ENTOMOLOGIST. 



123 



liaiulled witliout fear; but, unfortunately, in 

 order to dii^tinguish tlie sex, we arc generally 

 obliged to catch the little animal tirst; 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) antennie, and a seven-jointed 

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

 cally, this criterion is not of much value; aud 

 to ascertain whether a wasp can sting, we must 

 first take it iu 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, 

 I ho first of which is two or three times as 

 numerous in species as the second; namely, 

 y/csY, the Digger AVasps, or Fossorial Wasps 

 ( Fosaores) , and second!//, the True Wasps, or 

 wasps with folded wings {Diploptevyya.) There 

 i-^ no one obvious universal character by which, 

 witliout a solitary exception, these two groups 

 are distingnishable; but, with the exceptions 

 liercafter to be noted, they may be distinguished 

 by the following easily-observed criterions : 



1. None of the Digger Wasps have their 

 wings folded up iu repose. All the True AVasps, 

 on the coutrar)- — with the single exception of 

 an exotic genus (6'er«»i/».s), which has not as 

 yet been found in North America, and to a 

 l)artial extent, of another exotic genus {Ma- 

 aaris), found in this country exclusively in the 

 Kocky Mountain region — have their wings folded 

 in repose, in the singular manner shown in 

 Fignre li'!, where c represents the upper surface 

 (if the hind wing, witli lis front edge hooked 

 [Kis '.iii 1 on as usual to the 



^-—s^-Tirr^^^^ hind edge of the 



/a y i^: (^~^^*=ss=^g^^^_^ front wing; a, all 

 ^ ^■■- ■.■■-■-:---. -:^'~7: — .=^ 1 ""-^ tliat is visible from 



above of the upper surface of the front 

 wing, and h, the lower surface of the front 

 wing doubled over upon itself. Westwood 

 has remarked that this peculiar folding of 

 ilie wings "is so constant and character- 

 istic, that we look in vain throughout the 

 whole order {Hymenopteru) for any other in- 

 stance."' But, Westwood forgot that, in a 

 single genus of Chcdris Flies (Leiicospis), the 

 wings are folded in precisely the same manner, 

 as had been partly stated by himself in a 



311, as 



es, but not in the fc^^yes, of Ivvi 

 {Mutilla and J/;/.'//(^ On (In 

 le True Wasps, with the singh 



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 (Mutilla), or kidney-shaped^ 

 sexes of two genera {Trypoxylon^ 

 and in the males, 

 other genera {2 



contrary, all the True Wasps, witiTthc single 

 exception of one Australian genus {Parof/iii)- 

 have their eyes kidney-shaped, the hollow, or 

 scooped-out part of the kidney l'a<-ing the base 

 of the antenna. 



3. Most of the Digger Wasps, especially in 

 llie female sex, have their legs thickly set with 

 long stiff bristles or slender thorns, tlie use of 

 which we shall presently see. Certain excep- 

 tions which occur will be noticed hereafter, aud 

 the reason thereof explained. The.True AVasps. 

 on the other hand, always have their legs free 

 from bristles or thorns, although the joints of 

 their paws (irn'si) are often prolonged on each 

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

 sight to somewhat resemble small thorns. 



Having thus enabled the reader to tell I he 

 difi'erence between a Digger AVasp and a Tiue 

 AVas)), we will take up each group in its (uin 

 and explain and illustrate its pecniliar habit-. 



The Digger Wasps. 



Eveiy (ine knows that Blow-tlies or Meat-flies 

 will deposit their eggs, which are commonly 

 called •'fl3--blows,"' upon meat ; and that these 

 eggs soon afterwards hatch out into whitish 

 meat-feeding maggots, destined in the course of 

 a few weeks to reproduce the mother-fly ; after 

 which the same old cycle of phenomena is re- 

 peated again and again. In the same manner, 

 the thousands of different species of Moths and 

 Butterflies, the larva? of which feed upon the 

 leaves or the buds or the stems of ditlercnt 

 herbs, shrubs and trees, deposit their eggs in or 

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

 which their future larviB 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 dittereut 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— iu which state 

 alone they are capable of laying eggs— upon the 

 substances that they lay their eggs on. For in- 

 stance, all tlie Butterflies and Moths feed in (he 

 perfect state upon the nectar of flowers or other 



**ec Westwood's Inlruthiction, II , p. iSs, niul p. 1114, 



