194 



DOLICHOPIP^. 



mon to both sexes seem to claim the preference. The British 

 species then may be arranged as follows : 

 A. Antennae with the second joint transverse. 



B. Colour of the body not metallic, &c. Species 1, 2. 

 B B. Colour of the body more or less metallic. 



C. Third joint of the antennae elongated in both sexes, linear, not 

 broader than the second. Alulae tipped with black. Species 3. 

 C C. Third joint of the antennae broader than the second, usually 

 elongated in the male. Alulae pale. 

 a. Front blue. 



b. Hind femora unarmed. (Coxae with black bristles 2 : 2 : 1.) 

 c. Coxae all yellow. Species 4. 

 c c. Posterior coxae grey outside. Species 5,6. 

 b b. Hind femora with a spine or bristle in front near the tip. 



(Coxae with black bristles 3:1:1.) Species 7. 

 a a. Front the same colour as the thorax, or glossed with white. 

 d. Hind femora with a single spine in front near the tip. 

 e. Fore tibia with about three minute spines outside. 



Species 8, 9. 



e e. Fore tibia with a double row of spines outside. 

 /. Arista simple. Species 10, 11. 

 //. Arista capitate in male. Species 12. 

 d d. Femora with more than one spine about the tip. 



Species 13, 14. 

 d d d. Hind femora unarmed. 

 g. Face white. Species 15. 

 g g. Face black in the male. 



k. Outer appendages of hypopygium forked. Species 16. 



h 7i. Outer appendages of hypopygium simple. Species 17. 



A A. Antennae with the tip of the second joint elongate attenuated, 



received into a deep notch of the base of the third. Alulae tipped 



with black. 



i. Front the same colour as the thorax. Species 18, 19. 

 i i. Front blue. 



k. Hind metatarsus unarmed. Species 22. 



k k. Hind metatarsus armed at the base beneath in the male. 



Species 20, 21. 



k k k. Hind metatarsus armed towards the tip beneath in the 

 male. Species 23. 



The first two species form a group remarkable especially for the 

 departure from the typical number of abdominal segments in this 

 family. The antennae are not elongated, the third joint ovate 

 acute, the arista long and slender, nearly terminal, the face narrow, 

 yet more so in the male, the palpi ovate, hairy, longer than the 

 compressed proboscis, which they cover in front ; the lower orbit 



