304 BRITISH BEES. 



dorsal segment triangular, and its ventral plate straight 

 at its apex with the lateral angles reflected, making it 

 concave beneath and subcarinated longitudinally in the 

 centre, or also triangular and the sides of the prominent 

 angle deflected. 



The MALE difiers in having the antennae slightly 

 longer, in being rather more pubescent, more highly 

 and rather difl"erently coloured, and its terminal segment 

 merely rounded. 



NATIVE SPECIES. 



3. campestris, Panzer, ^ ? . 6-9 lines. (Plate XV. 

 fig. 2. The fig. marked (^ by mistake for ? .) 

 campestris, Kirby, ? . 

 Rossiella, Kirby, J*. 

 Leeana, Kirby. 

 Franciscana, Kirby. 

 subterranea, Kirby. 



2. Barbutellus, Kirby, $ ? . 6-9 lines. 



3. vestalis, Fourcroy, $ $ . 6-10 lines. (Plate XV. 



fig. 2 ? .) 

 vestalis, Kirby, ? . 



4. rwpesifm, Pabricius, (J ? . 6-10 lines. (Plate XV. 



fig. 1 (? ? ■) 

 albinella, Kirby, $. 



GENERAL OBSERVATIONS. 



Named from a, privative, Trddo^, affection; that is 

 to say, without affection, from their habit of leaving 

 their young to be nurtured by others, in allusion to 

 their parasitical instincts, for the young of these bees 

 are brought up in the nests of the Bombi. They form 

 the only instance in bee-parasitism of the parasite 



