SCIENTIFIC SURVEY. 



157 



sliort, thick and white. How the larvte are fed and the pupaj are 

 cared for by the neuters, and the habits of ants generally, are found 

 in all the books. Sometimes the pupse are naked, but generally 

 they are enclosed in thin cocoons. 



Chrysidce. These insects are very different from the ants in their 

 oblong compact form, their nearly sessile oblong abdomen, having 

 only three to five rings visible, the remaining ones being drawn 

 within, forming a long, large jointed sting-like ovipositor wh^ich 

 can be thrust out like a telescope. The abdomen beneath is con- 

 cave, and the insect can roll itself into a ball on being: disturbed. 

 They are green or black. The sting has no poison-bag, and in this 

 respect, besides more fundamental characters, the Chrysis ap- 

 proaches the Ichneumon family. They best merit the name of 

 " Cuckoo-flies," as they fly and run briskly in hot sun-shine, on 

 posts and trees, &c., darling their ovipositor into holes in search of 

 other hymenoptera, &c. in which to lay their eggs. Their larvae 

 are the first to hatch and devour the food stored up by other fosso- 

 rial bees and wasps. "St Fargeau, however, w'ho has more 

 carefully examined the economy of these insects, states that the 

 eggs of the Chrysis does not hatch until the legitimate iuhabitant 

 has attained the greater part of its growth as a larva, when the 

 larva of the Chrysis fastens on its back, sucks it, and in a very 

 short time attains its full size, destroying its victim. It does not 

 form a cocoon, but remains a long time in the pupa state." 



" In the Ent. Mag. has been noticed the discovery of Eedijcliriim 

 bideniulum, which appears to be parasitic upon Psen caliginosus ; 

 the latter insect had 'formed its cells in the straps of a thatched 

 arbor, as many as ten or twelve cells being placed in some of the 

 straws. Some of the straws, perhaps about one in ten, contained 

 one or rarely two, of the Iledychrum, placed indiscriminately 

 amongst the others. Walkenaer, in his Memoirs upon Halietus, 

 informs us that Iledychrum luciduliim waits at the'mouth of the 

 burrows of these bees, in order to deposit its eggs therein ; and that 

 when its design is perceived by the bees, they congregate together 

 and drive it away. "St. Fargeau states that the females of Hed- 

 ychrum sometimes deposit their eggs in galls, while H. rcgium 

 oviposits in the nest of Megachile muraria ; and ho mentions an 

 instance in which the bee, returning to its nearly finished cell, laden 

 with pollen paste, found the Iledychrum in its nest, which it 

 attacked with its jaws ; the parasite immediately, however, rolled 

 itself into a ball, so that the Megachile was unable to hurt it; it 



