138 



THE AMERICAN ENTOMOLOGIST. 



often infest badly kept collections of in- 

 sects. 



It is very remarkable that, although all the 

 Digger Wasps feed in the larva state upon liv- 

 ing animal matter, they all of them in the per- 

 fect or winged state feed exclusively upon veg- 

 etable substances, such as the honey and pollen 

 of flowers. Hence it is the more wonderful, 

 that they should be impelled by nature to store 

 up for their future offspring a supply of sucli 

 food, as would be utterly distasteful to them- 

 selves. 



The Ti'iie Wasps— Solitary Species, 

 The solitary True "Wasps scarcely differ in their 

 habits from the Digger Wasps, except that such 

 genera {Odynerus, etc.) as construct their nests 

 in sandy banks, in the interstices of stone walls, 

 in holes bored by other insects in wood, etc., 

 never dig with their two front legs, or scrabble 

 out the excavated fragments with their four 

 hind logs, after the usual fashion of the Digger 

 Wasps. On the contrary, they always excavate 

 their holes solely with their powerful jaws, 

 having first, when they are boring info hard 

 earth, softened it with their saliva; and they 

 always carry the excavated fragments out with 

 their mouths, instead of scrabbling them out 

 with their legs.* The reason is obvious: their 

 legs, as stated above, arc smooth, and, there- 

 fore, not adapted for digging, scratching and 

 scrabbling. Many genera, however, construct 

 mud-nests in the open air, and we present here- 

 with a sketch from nature (Figure 110, h), of 



[Fig. 110] 



(Joloi-o— (tt) Ijlaok uiul yellow; (b) mud- color; (c) nunl- 

 color and green. 



that built h\ a common North American 

 species, belonging to such a genus— the Frater- 

 nal Wasp {Eumeiiesfraterna, Say, Fig. 110, a). 

 Figure 110, c, shows the same nest cut open 

 shortly after it was built, so as to display the 

 close and compact manner in which the small 

 green caterpillars, with which it was stored, are 



•See, ou this subject, St. Fargoiiu, Hymenopl, 11, p. b!)0, 

 !i ud Reaumur, «s quoted there— afar more reliable authority 

 lor the hiihits or imv insect than St, Fargean, 



arranged by the mother-wasp. According to 

 Harris,* the Fraternal Wasp employs the 

 pernicious caukerworms {Anisopteryx vernata, 

 Peck) for this purpose ; but it certainly can 

 never do so near Kock Island, Ills., for there 

 are no caukerworms in that neighborhood, and 

 j^et this wasp is very abundaut there. The nest 

 itself is sometimes firmly cemented under the 

 loose bark of a tree, sometimes attaclied to the 

 stem of a large weed in the open air, and some- 

 times to a leaf. We possess the leaf of some 

 deciduous plant sent us by a correspondent, 

 which exhibits no less than five of these nests, 

 all placed close together on its lower surface, 

 and from one of these the perfect insect was ac- 

 tually bred. So that, in this latter case, it would 

 seem that the nests would necessarily all fall to 

 the ground in the winter, and the larva — which 

 does not hatch out into the perfect wasp state 

 until the summer after that in which the nest 

 was built — would be exposed all through the 

 inclement season of the year to lie soaking on 

 the ground after every storm of rain or snow. 

 Possibly, however — as we know that the larvse 

 of many moths will, under such circumstances, 

 fasten the leaf, or loaves, to which their cocoons 

 arc attached, by silken cords to the twig — tlie 

 mother-wasp, in this case, might have taken the 

 precaution to cement the leaf to the twig by the 

 same clay mortar of which it constructs its nest. 



The True Wasps— Social Species. 



The Bald-faced Hornet (Vespa macidata, 

 Linn, Fig. Ill) , is so well known throughout the 

 Northern States, that it may be taken as a 

 familiar example of the habits of this group. 

 " Natural paper - 

 makers from the 

 beginning of time,'" 

 as Harris has felici- 

 tously called them, 

 these insects have, 

 for ages immemo- 

 rial, done what 

 man, with all his 



Coiors-Browu-black and crcniK-yellow. boastcd prC-Cmi- 



nencein intellectual power, has only succeeded in 

 doing within the last few years ; that is, they man- 

 ufacture paper, not out of rags, but out of wood. 

 Alighting upon .some wooden surface exposed 

 to the weather, they gnaw off with their strong- 

 jaws the minute filaments of wood, which have 

 become partly detached by the action of the ele- 

 ments) and chew them up into a fine pulp, which 

 they afterwards spread out into the thin sheets of 



[Fig. ni.] 



^Injurious Insccls, y, ill. 



