DURHAM DIPTERA. 109 



XXI. 186. 



3 (4). Frons with a deeply impressed middle line, and in 



the female also with deep side lines. 



(982. fenestrate, L.) 



4 (3). Middle frontal line only slightly impressed, and only 



a trace of faint side lines in the female. 



(984. glabifrons, Mg.) 



Family XXIL— CYRTID^E. 



1 (2). Proboscis short and hidden ; antennae inserted nearer 



the vertex. 187. Oncodes, Ltr. (985. gibbosus, L.) 



2 (1). Proboscis entirely awanting ; antennae inserted nearer 



the mouth. 



188. Acrocera, Mg. (986. globulus, Pz.) 



Family XXIII.— EMPIRE. 



TABLE OF GENERA. 



1 (20). V.3. forked (V. 10). 



2 (3). Fore coxae as long as, or longer than the much 



thickened fore femora. 



Hemerodromia, Mg. (204) 



3 (2). Fore coxae not so long as the normal fore femora. 



4 (7). Proboscis much longer than the head (VI. 19). 



5 (6). Hind legs longer than the rest. Hind femora 



normal. Empis, L. (192) 



6 (5). All legs about the same length. Hind femora much 



thickened. Pachymeria, Steph. (193) 



7 (4). Proboscis not longer than the head. 



8 (9). 0.5 1 rather shorter than O.6 1 . Wings spotted. 



Ardoptera, Mcq. (205) 



9 (8). 0.5 1 longer than O.6 1 . Wings generally not spotted. 



10 (11). Third joint of antennae lengthened, and terminating 



in a long bristle. Costa ending at the wing tip. 

 207. Trichopeza, Rnd. (1108. longicornis, Mg.) 



11 (10). Neither the third antennal joint nor its arista specially 



long. Costa produced beyond the tip of the wing. 



12 (13). O.8. (anal angle of the wing) very small. Wings 



wedge-shaped. Clinocera, Mg. (203) 



