192 HYMENOPTERA ACULEATA. 



of the Andrenidie besides the form of the labial palpi are — 



the usually short ovate tongue, the transverse labrum, the 



ovate subdepressed abdomen with its anal orifice terminal 



in both sexes, and the densely hairy femora and tibife of 



the ? which serve as the pollinigerous organs. This latter 



character is absent in 82:>hecodes and Nomada. Ten genera 



occur in Great Britain, which may be tabulated thus : — 



(12) 1. First joint of labial palpi not many times 

 longer than the apical joint. 



(9) 2. Anterior wings with three submarginal 

 cells. 



(8) 3. Apical joint of antennas not obliquely 

 truncate. 



(7) 4. Lora absent, second and third joints of 

 the antennsB subequal. 



(6) 5. Sides of the tongue rounded to the apex, 

 insects black or black and red, pronotum 

 scarcely hairy ; ? •nithout tibial pollen 

 brushes Sphecodes. 



(.5) 6. Sides of the tongue sinuate just before the 

 apex, insects rarely red except occa- 

 sionally in the ^ sex, pronotum hairy, 

 generally densely so; $ with well- 

 defined pollen brushes Halictus. 



Lora present, third joint of antennas twice 



as long as the second .... Andeena. 

 Apical joint of antennsB obliquely trun- 

 cate ClLISSA. 



Anterior wings with two submarginal 



cells. 

 Hind tibife and tarsi not dilated, clothed 



with very long hairs .... Dasypoda. 

 Hind tibite and tarsi dilated, not clothed 



with long hairs Macropis. 



First joint of labial palpi many times 



longer than the apical joint. 

 Wings with two submarginal cells. 

 Marginal cells subtruncate, appendicu- 



lated _ . Panurgus. 



Marginal cells pointed, not appendicu- 



lated . 

 Abdomen without pale pubescent bands . Dufourea. 

 Abdomen with pale pubescent bands . Rophites. 



Wings with three submarginal cells . . Nomada. 



SPHECODES, Latr. 

 The black and red colour of the species of this genus is 

 their most striking characteristic, and although the males 



