152 BEES OF GREAT BRITAIN. 



Female. Length 4 lines. Black, closely and strongly punc- 

 tured ; the head and thorax have a sparing cinereous pubes- 

 cence ; the scutellum rounded behind and armed on each side 

 with a short stout tooth ; the wings fusco-hyaline, a dark fus- 

 cous stripe traversing the marginal cell, the apical margins also 

 have a fuscous cloud. Abdomen incurved, shining, the apical 

 margins of the segments testaceous ; the apical segment sub- 

 angulate. B.M. 



Male. This sex only differs from the female in having the 

 margin of the apical segment of the abdomen rounded. 



This is a scarce insect, only occasionally met with : it has 

 occurred in Hampshire, at Birch Wood, Kent, and at Wey- 

 bridge ; but only one or two specimens at each locality. 



2. Stelis phaeoptera. 



S. atra, punctulatissima, albido subpubescens ; ano rectangulo. 



Apis phaeoptera, Kirby, Mon. Ap. Angl. ii. 232. 40 . 

 Megachile phaeoptera, Latr. Hist. Nat. Ins. ii. 527. 2. 



Spin. Ins. Lig. fasc. 1. 136. 4. 

 Stelis phseoptera, St. Farg. Hym. ii. 527. 2. 



Smith, Zeol. iii. 1154. 2. 



Nyland. Ap. Boreal p. 274. 1. 



Female. Length 4 lines. Black, closely and strongly punc- 

 tured ; the face, cheeks, thorax on the sides and beneath, having 

 a thin hoary pubescence ; the posterior margin of the thorax 

 rounded, the scutellum coarsely punctured, unarmed; wings 

 fusco-hyaline, the apical margins clouded, a darker cloud oc- 

 cupying the marginal cell. Abdomen shining, the apex in- 

 curved and pointed, the apical segment subcarinate. B.M. 



Male. Exactly resembling the female, the margin of the apical 

 segment of the abdomen entire. B.M. 



This insect has been taken in Battersea Fields, usually in the 

 flowers of the Mallow. The female has been observed entering 

 the burrows of Osmia fulviventris in an old post : on one occa- 

 sion it flew out to a short distance and settled on another post : 

 at this moment the Osmia returned and entered the burrow : 

 immediately on her coming out the Stelis again re-entered : 

 this proceeding was repeated several times, probably until the 

 cell was properly furnished with food for the parasite- 



