HYMENOPTERA. — CRABRONIDA. 193 
having the ocelli in some of the species arranged in a slight curve, and 
not in a triangle; and the anterior tibiz in the males of some of the 
species are singularly dilated into a broad horny plate.* In Crabro 
tibialis Pz., the basal joint of the anterior tarsi is also furnished with 
a broad wing-like membrane, overlooked by St. Fargeau and Brullé, 
who form this insect into the genus Corynopus, incorrectly stating 
that the anterior tarsi of the males are simple. 
The species whose economy has been clearly traced make their cells 
in wood, boring into palings, posts, willow-stumps, &c. (C. xylurgus 
Shk.). Crabro cephalotes, one of the most ferocious and predatory of 
the group, has simple anterior tarsi, but the posterior tibiae are spurred. 
This species, according to Mr. Shuckard, employs its mandibles in 
forming a cylindrical cell in decaying trees, passing the particles of wood 
beneath them, and ejecting them behind by means of the spines with 
which the posterior tibia are armed. C. cribrarius, according to 
Latreille, provisions its cell with the larvee of a small Pyralis, which 
feeds upon the oak (Tortrix chlorana); but Mr. Shuckard states 
‘that it, as well as C. patellatus, employ Diptera for this purpose, as is 
also the case with other species. I have captured C. (Crossocerus 
St. F.) leucostoma, burrowing into rotten wood, and also carrying its 
prey, which consisted of a specimen of Anthomyia pluvialis Mezg.+ ; 
and I am indebted to Mr. Pickering for specimens of a nest found in 
rotten wood, covered with the remains of blue-bottle flies, from which 
I reared Crabro vagus, the larva of which is white and fleshy, with a 
scaly head bent under the breast, the extremity of the body being also 
incurved (fig. 81. 15. larva of the natural size, 16. ditto magnified, 
seen from beneath, 17. ditto seen laterally). It is destitute of legs, but 
the segments are dorsally provided with a transverse elevated ridge, 
* Tn Crabro cribrarius $ (fig. 81. 12.), this dilatation is covered with small mem- 
branous transparent dots, which, as Latreille observes (Hist. Nat. xiii. 321.), 
gives it the appearance of being pierced, as indeed it was supposed to be by Ro- 
lander, who thought it was used by the males as a riddle through which the pollen 
of flowers was passed, the finer particles only serving for the impregnation of the 
plant! De Geer, however, disproved this notion by figuring the limb correctly. 
(Mem. tom. ii. tab. 28. f. 2, 3.) 
+ Bouché has described the larva of this species ( Naturgesch. d. Ins. p. 178.), as 
well as that of Stigmus (Diodontus minutus Fab. ). Réaumur’s fig. 14. pl. 27. vol. vi. 
reared from cells filled with flies resembling house flies (fig. 1. k.), is apparently 
a small yellow-spotted Crabro, it being stated that its fore-wings “ne se plient 
jamais.” In Insect Architecture (p. 52.) it is erroneously stated to belong to the 
wasp-genus Eumenes. 
VOL. Il. oO 
