1012 



Insects. 



colony of Halicti or Andrenae. I think it, however, very probable, 

 that they frequently make use of a ready-formed burrow, and that they 

 furnish a supply of liquid honey, in the manner of Colletes or Cera- 

 tina. I am thus led to dissent from the generally received opinion 

 of their being parasitic ; and shall endeavour, by future observation, 

 to place their true habit beyond a doubt. Walckenaer, Serville, and 

 St. Fargeau, agree in considering Sphecodes to be parasitic upon Ha- 

 licti ; my own observation has shown me that they are as frequently 

 to be found in company with colonies of Andrenae : and, if parasitic, 

 I think it will eventually be found that they are by no means confined 

 to the species of the genus Halictus. 



Genus. — Sphecodes, Latreille, St. Fargeau. 

 Sphex, Linnaeus. Nomada, Fabricius. Melitta, Kirby. 



1. Sphecodes gibbus, male. 2. Ditto, female. 3. Sphecodes Sphecoides, male. 4. Ditto, female. 

 5. Sphecodes subquadratus,/e/waZe. The head of the male is of the same subquadrate form. 



Sp. 1. Sphecodes gibbus, St. Fargeau. 



Sphex gibbus, Linnaeus. Nomada gibba, Fabricius. 



Melitta gibba, Kirby. 



Fig. 1, 2. 



Female. — Length 4 — 4j lines. Black, 

 the thorax, finely and closely punctured. 



Head the same width as 

 Mandibles dark ferrugi- 



nous, black at their base. Antennae piceons beneath. Thorax deep- 

 ly and closely punctured, thinly clothed beneath and upon the sides 

 with hoary pubescence. Anterior tibiae slightly ferruginous in front. 



