British Hymenoptera. 



197 



$ . With a dense ventral pollen-brush composed of beautifully 

 straight spirally-grooved hairs. 



(6) 1, 



(3) 2. 

 (2) 3. 

 (5) 4. 



(4) 5. 



(^ front tarsi dilated ; $ mandibles largely flat- 

 tened in front, the flattened portion wide at the 

 base and deeply furrowed, the groove extend- 

 ing almost to the clypeus. 



^ posterior tibiae dilated, thicker than the femora ; 

 2 scopa orange-red, pale whitish at the base, 

 extreme apex darker . . . . . . . . maritiina. 



(J posterior tibias not dilated, scarcely so thick 

 as the femora ; scopa of $ dark, fulvous in 

 the middle. 



Basal segments of abdomen covered with long 

 fulvous hairs ; apical segments with black 

 hairs; ^ with basal joint of anterior tarsi 

 much longer than wide, its sides straight ; $ 

 without pale apical bands to the abdominal 

 segments . . . . . . . . . . . . circumcmcta. 



Basal segments of abdomen with scattered hairs ; 

 ^ with tlie basal joint of the anterior tarsi as 

 wide as long, its sides slightly curved ; J with 

 pale apical bands to the segments . . . . Willughbiella. 



^ front tarsi simple ; 5 mandibles only flattened 

 and grooved towards the apex. 



6th segment of abdomen in ^ not covered with 

 pale hairs ; scopa of 5 ^^^ white ; the apical 

 margins of the segments naked. 



(^ 6th segment entire or nearly so ; J scopa 



bright orange-fulvous . . . . . . . . centuncularis. 



^ with crest of 6th segment distinctly emargi- 

 nate; 5 scopa not bright orange. 



^ tarsi pale ; 7th segment spined ; 5 scopa 



entirely pale . . . . . . . . . . pyrina. 



(J tarsi black ; 7th segment not spined ; J scopa 



black on the two apical segments . . . . ligniseca. 



^ 6th segment clothed above with a short ad- 

 pressed pale pubescence ; J scopa white or 

 nearly so ; apical margins of the segments 

 beneath fringed . . . . . . . . . . argentata. 



1. MegacMle maritiina, Kirb. (PI. IX., figs. 2 — 2b). 

 Kirb., Mon. Ap. Angl., ii., p. '242 ; Smith, Cat. Brit. 

 Hym., 2nd ed., p. 179. 



Black, clothed with brown or golden brown hairs ; <? with the 

 anterior tarsi white, dilated ; posterior tibiae curved, dilated, thicker 

 than the femora ; basal joint of tarsi very wide at tlie base, narrow 

 at the apex ; 5 with the mandibles largely flattened in front, with 

 a deep groove extending almost to the clypeus ; scopa pale whitish 

 at the base, orange-red in the middle, and dark at the extreme 

 apex. 



