206 DURHAM DIPTERA. 



XXIX. 321. 



321. Conops, L. 



3 (4). Scutellum yellow or red-brown. (1628. vesicularis, L.) 



4 (3). Scutellum black, with at most the extreme edge 



yellow. 



5 (6). Hind femora yellow, at most slightly brown on the 



middle. (1629. quadrifasciata, Deg.) 



6 (5). Hind femora black; the base, and sometimes the tip, 



yellow. 



7 (8). Frons wholly black. (1630. ceriiformis, Mg.) 



8 (7). Frons black and yellow. 



9 (10). Face yellow, with black spots on the jowls. 



(1624. strigata, Mg.) 



10 (9). Face and jowls all yellow, at most a black centre 



stripe. (1632. flaviftes, L.) 



11 (2). Femora abnormally thickened at the upper side base 



as if swollen ; second abdominal ring much 

 narrower and longer than the others. 



322. Physocephala, Schin. 



12 (13). Ground colour of the abdomen all yellow. 



(1633. nigra, Deg.) 



18 (12). Ground colour of the abdomen black, and partly 

 orange, at least on the second segment. 



(1634. rufipes, F.) 



14 (1). Third antennal joint with a short two-jointed style- 



like dorsal arista (III. 47); ocelli present. 



Sub-Family Myopin^e. 



15 (16). Proboscis only elbowed at the base. 



323. Zodion, Ltr. (1635. cinereum, F.) 



16 (15). Proboscis elbowed at the base and at the middle, 



the front portion shutting back like a pocket- 

 knife (VI. 27). 



17 (22). Face only moderately lengthened ; jowls at most as 



long as the diameter of the eye, generally shorter. 



18 (21). Antennae longer than the frons; frons yellow in front, 



black behind. 



