British Hijmcnoptera. 227 



rounded posteriorly, and the abdomen has no white 

 lateral spots. Length 5 — 6 mm. 



Hah. Not rare. London district, Norwich, Lowestoft, 

 Southwold, Littlehampton, Bournemouth, Tunbridge 

 Wells, Keigate, Chobham, &c. 



The (? is very distinct from any other species. 



Andrena, F<ih. 



Fab., Syst. Ent., p. 376. For figures of generic cha- 

 racters see F. Smith, Cat. Brit. Hym., 2nd ed., pi. vi. 



Tongue lanceolate ; paraglossae not acute ; labial palpi 

 4-jointed ; maxillary palpi 6-jointed. Anterior wings 

 with three submarginal cells. 3 generally with the 

 head wider than that of the ? , the vertex often sub- 

 quadrate ; in some species with the head enormously 

 enlarged, and the mandibles long and falcate ; the size 

 of the head, however, varies very much amongst speci- 

 mens of the same species. Clypeus sometimes white. 

 Abdomen generally narrower than in the $ , and with 

 the 8th or apical ventral plate narrowed and elongate 

 towards the apex, generally somewhat dilated at the 

 extremity, and often emarginate ; the 7th ventral plate 

 hidden in nearly all the species under the 6th ; the geni- 

 talia of the males of the diiierent species bear a very 

 strong general resemblance to one another, and in this 

 respect the genus contrasts curiously with Halictus, 

 Prusopis, &c., where the genitalia of each species give 

 such characteristic distinctions. ? with the abdomen 

 usually ovate, sometimes nearly glabrous, but generally 

 either clothed all over with long hairs, or else banded 

 with pale hairs at the apex of the segments ; 5th and 

 6th segments densely clothed with hairs, which are often 

 of a different colour to those on the rest of the abdomen. 

 Apical dorsal valve with its centre glabrous, the glabrous 

 portion of a triangular shape ; posterior legs of the ? 

 with a tuft of curled hairs on the trochanters, generally 

 called the " lloccus ; " this in many species is composed 

 of very long hairs, and forms a prominent character ; 

 the posterior tibiae are outwardly clothed with long hairs, 

 which form the " scopae," and on their inner surface, or 

 that towards the body, they are clothed with hairs, 

 having flattened and dilated apices, so formed probably 

 for cleaning purposes. At the base of the tibiae is a 



