62 Entomological Society. 



which she afterwards finished ; and which she has now deserted, as I 

 have not seen her for many days. 



" The nest is firmly fixed on the lime and gravel surface of the 

 wall of the hot-house, and is itself nearly of an equal hardness with 

 it. I do not doubt but each cell contains one or more eggs, and 

 from which in due time young insects will come forth. 



" The genus Crahro of Fabricius is a part of Linnseus's genus Sphex ; 

 and I find that the latter author has given a short account of the mode 

 adopted by the Sphex sahulosa (now called Ammophila sabulosa), of 

 making its hole in the sand, and of depositing its eggs in the bodies 

 of insects (see Syst. Nat., edit. 12, p. 941, vol. ii.) ; and he also de- 

 scribes (p. 942) how the Sphex figulus makes its nest in holes in wood, 

 and * nidum argilld claudit.' The mode there described of that in- 

 sect using clay is similar to that adopted by the Crahro cephalotes, but 

 I did not notice it conveying a spider, or the larva of any other insect, 

 into its nest; though perhaps, if the cells were examined, some 

 such insect might be discovered within them. 



" A few days ago I observed some sparrows on their nest in a tree 

 in my garden pulling about something which appeared like a bundle 

 of white feathers ; a short time afterwards 1 went to water some 

 flowers below the same tree, when to my surprise I found on the 

 ground a beautiful nest of the Vespa Britannica. The sparrows 

 having however dug holes with their bills in the lower portion of 

 it, in search of larvse, or of something to devour, had a good deal 

 injured this most elegantly-made nest." 



In a subsequent communication Mr. Hogg states that he is quite 

 certain the insect which formed the nest " is the same as that which 

 I sent to you some few years ago, and which you named ' Crabro 

 cephalotes ' ; and the reason of my troubling you with my commu- 

 nication was, that I strongly suspected that its economy in nidifi- 

 cation has never been fully ascertained. But as I before said, I 

 have not at hand Shuckard's * Monograph of the Fossorial Hyme- 

 noptera,* or any other modern work which describes the species. 

 That it may sometimes make its nest in the holes of rotten wood or 

 in sand-banks, I do not know ; but that it does not always do so, 

 the present example clearly proves. 



'* One of the insects (probably the male) I only saw one day ; it 

 was inside, flying up and down the glass light of the hot-house. The 

 other, or the female, was then as usual forming her nest. But I did 

 not capture either of them, because I thought they would make 

 more cells, and I should have frequent opportunities for doing so. 

 Should either of them return, I will take care and secure it. 



"I yesterday (22nd July 1845) opened one of the cells, when 

 I found only a single larva^ which is soft, yellowish- white, apodous, 

 and resembling that of the common wasp. The entire cell was lined 

 with a white membrane ; but I did not notice, after the most minute 

 examination, any fly, spider, or any remains whatever of any insect, 

 and no egg. This was the same cell which I mentioned in my last 

 letter as that in which L^aw the female Crabro sitting, and then 

 closing up its top. 



