178 MODERN CLASSIFICATION OF INSECTS. 
florisomne (a solitary bee); and that the larve produced from the eggs 
of the former feed on the larvee of the Chelostoma, and undergo their 
metamorphoses in the cells prepared for these last * (Ent. Mag. vol. 3, 
p- 387.) Saint Fargeau, however, who has more carefully examined 
the economy of these insects, states that the egg of the Chrysis does 
not hatch until the legitimate inhabitant 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, de- 
stroying its victim. It does not form a cocoon, but remains a long 
time in the pupa state. (Enc. Méth. tom. x. p. 9.) 
In the 21st Number of the same Magazine (p. 77.) has been noticed 
the discovery of Hedychrum bidentulum, which appears to be para- 
sitic upon Psen caliginosus ; the latter insect had formed its cells in the 
straws of a thatched arbour, 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 Hedychrum, placed in- 
discriminately amongst the others.” Walckenaer, in his Memoir 
upon Halictus (p. 33.), informs us that Chrysis [Hedychrum] lucidula 
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. 
M. le Comte de Saint Fargeau states, that the females of Hedychrum 
sometimes deposit their eggs in galls, whilst H. regium oviposits in 
the nest of Megachile muraria ; and he mentions an instance in which 
the bee, returning to its nearly finished cell laden with pollen paste, 
found the Hedychrum 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, however, bit off its four wings 
which were exposed, rolled it to the ground, and then deposited its 
load in the cell and flew away, whereupon the Hedychrum, now wing- 
less, had the persevering instinct to crawl up the wall to the nest, and 
there quietly deposit its egg, which it placed between the pollen paste 
and the wall of the cell, which prevented the Megachile from seeing 
it. (Ene. Meéth. tom. x. p. 8.) 
* The passages connected with this history, published in 1833, in conjunction with 
others which appeared in the same work, recall to mind the existence of feelings 
which I am happy to say have long ceased. The date of my memoir upon the 
Chalcidide, published in the Zoological Journal, and the amount of materials known 
to have been collected by me upon that family, and still intended for publication, 
are sufficient to show that they ought never to haye been entertained, 
