British Hij incuujjtent . 



281 



(20) 21. ^ , face clothed with black hairs ; J and ^ , 

 abdomen clothed with black at the base and 

 red at the apex, or with pale, but in the 

 latter case with no black on the 3rd and 4th 

 segments. 



(23) 22. Eed on the apical segments in sharp contrast 

 with the black of the preceding ; $ and ^ 

 with the hairs of posterior tibia; red 



(22) 23. Black of the base of the abdomen gradually 

 shading into the red of the apex ; or the 

 abdomen entirely greyish with tlie ajiex red, 

 and without a black central band . . 



(!'.)) 2'1. J , posterior metatarsi outwardly fringed with 

 long hairs ; $ and ^ > intermediate meta- 

 tarsi not produced at the external apical 

 angle. 



(20) 25. Abdomen with the 3rd and following segments 

 red in all the sexes . . 



(25) 26. Abdomen never with more than the 4th and 

 following segments red. 



(28) 27. Basal segments of the abdomen entirely black 



in the ^ ; thorax entirely black in J and ^ laindarius. 



(27) 28. Basal segments of the abdomen not black in 

 the (J ; thorax with a pale band in front in 

 the 2 and ^ • 



(30) 29. (J , genital armature with the sagittse curved 

 outwards at the apex, posterior metatarsi 

 much narrowed at the base ; $ and ^ , face 

 wider across the eyes than long, somewhat 

 square, very little narrowed to the apex . . soroemis, va 



(29) 30. J , genital armature with the sagittse curved 



at the apex inwardly, and forming a semi- 

 circular hook ; 5 and ^ , face narrow, longer 

 than wide across the eyes, considerably nar- 

 rowed to the apex . . . . . . . . pratorum. 



Derhaviellus. 



pomontm. 



lapponlciis. 



1. Bomhus Smithianus, White. (PI. XII,, fig. 3). 



White, Proc. Linn. Soc. (1851); Smith, Cat. Brit. 

 Hym., 2nd ed., p. 202. 



Head clothed with black hairs ; thorax above with bright, 

 rather dark, fulvous hairs, abdomen with paler ; beneath entirely 

 clothed with black hairs, except the apical segments of the 

 abdomen. 



<y . Head clothed with black hairs ; face with a little pale pube- 

 scence below the antenna; ; cheeks shining, about as long as their 

 apex is wide ; labrum impressed across the middle, clothed with 

 black hairs ; antenna; with the joints slightly rounded in fi-ont ; 

 3rd joint of the flagellum considerably shorter than the 2nd. 

 Tliorax clothed with bright fulvous hairs of a richer darker colour 

 than those of any of our other species; wings smoky brown. 

 Abdomen with paler, yellower hairs, its base rather darker, and 7tli 



