DTJKHAM DIPTERA. 151 



XXIV. 237. 



11 (10). Third antennal joint shorter than the arista. 



12 (13). Fifth fore tarsal joint with 4-5 remarkably long hairs; 



fore metatarsi not dilated at tip, and hardly longer 

 than the next joint. (1290^-. rivalis, Lw.) 



18 (12). Fifth fore tarsal joint with no long hairs ; fore meta- 

 tarsi clubbed at the tip, and twice as long as next 

 joint. (i29of. patula, Lw.) 



14 (3). Male mid coxae without an apical spine, but some- 



times with a tuft of black bristly hairs. 



15 (16). Abdomen distinctly silvered above. 



(1295. micans, Mg.) 



16 (15). Abdomen not silvered above. 



17 (18). Hind legs lengthened, thickened, and black ; mid 



tarsi with the fourth and fifth joints dilated. 



(1297. crassipes, Mg.) 



18 (17). Legs normal. 



19 (20). Outer anal appendage of the male forked. 



(1292. nasuta, Fin.) 



20 (19). Outer anal appendage of the male not forked, simple. 



21 (22). Outer anal appendage of the male with a band-like 



tuft of hairs before the point. 



(129 1. pencillata, Lw.) 



22 (21). Outer appendage without the hair tuft. 



23 (26). Fore femora with a row of strong hairs beneath. 



24 (25). Face black in the male ; fore coxa? black haired. 



(1293. pectinata, Lw.) 



25 (24). Face whitish in both sexes ; fore coxae white haired. 



(1294. consobrina, Ztt.) 



26 (23). Fore femora without a row of strong hairs beneath ; 



outer lamellae of the male broadened out like a fan 

 at the end, pointed above, and all bitten out and 

 ciliated. ( I2 99- riparia, Mg.z=.prczrosa, Lw.) 



23 7i- Systenus, Lw. 



All at present considered very rare. They live on the 

 ulcerative sap from trees. 



1 (4). V.3. and V.4. strongly approximating before the tip. 



