Insects, 1011 



Descriptions of the British Species of Bees belonging to the Genus 

 Sphecodes of Latreille. By Frederick Smith, Esq., Curator 

 to the Entomological Society. 



The British species belonging to this genus have hitherto remained 

 in great confusion, no one having apparently bestowed upon them 

 sufficient attention to disentangle them. I think I shall be able to 

 show, that notwithstanding their uniformity in colour, they are abun- 

 dantly distinct in form ; and I hope to point out other distinguishing 

 characters, whereby they may be easily separated. Linnaeus and Fa- 

 bricius have both described a species under the trivial name of gibba; 

 but the specimens labelled " gibba" in the Banksian cabinet are distinct 

 from that so named by Linnaeus, and preserved in the Linnean cabi- 

 net, the latter being the " Sphecoides " of Kirby. But as specimens 

 agreeing with the Fabrician insect are also in the collection of Linnaeus, 

 that author doubtless considered them all as constituting but one spe- 

 cies ; and the descriptions of both authors would, in fact, point out 

 the Sphex gibba of Fabricius — an insect now generally known as the 

 Sphecodes gibba. 



Most authors who have described or alluded to this genus since the 

 publication of Mr. Kirby's Monograph, have described them as para- 

 sitic insects ; but I am not aware that any one has proved them to be 

 so. The supposition I believe to be founded on their wanting th.3 

 pollenigerous organs, combined with a habit they have of entering 

 holes, or burrows in banks, as if in search of the nest of some bee, 

 wherein to deposit their eggs. This, however, is but slight evidence. 

 There is, perhaps, no insect which has the habit of entering the bur- 

 rows of other species, more constantly than Trypoxylon figulus, — an 

 insect which I have ascertained to be no parasite, since it furnishes 

 its nest with spiders ; still, I have never observed it burrowing. 

 Again, Ceratiua is destitute of pollenigerous organs, but this insect 

 has been proved by Mr. Thwaites to construct its own nidus. Reau- 

 mur has described Sphecodes as excavating its burrows in the bare 

 sections of banks to the depth of nine or ten inches, in which to de- 

 posit its eggs, together with a supply of pollen and honey ; Mr. Kirby 

 appears to have entertained the same view ; and my own observation 

 leads me to a similar conclusion. On several occasions 1 have seen 

 these bees busily engaged in burrowing ; and last summer I watched 

 one thus employed for a considerable length of time. All that I have 

 seen engaged in this way had selected a spot, either in the midst of a 



