148 DURHAM DIPTERA. 



XXIV. 230. 



8 (5). Hind trochanters black or brown ; base of hind 



femora not yellow. 



9 (12). Fore coxae with only pale hairs. 



10 (11). Face of male very narrow but continuous, silvery 



white; palpi small, whitish. 



(1267. palustris, Verr.) 



11 (10). Face of male broad, greenish grey ; palpi large and 



black; acrostichal bristles almost absent. 



(1268. Icesus, W.) 



12 (9). Fore coxae with black hairs. 



13 (18). Legs mainly black, i.e., the tibiae may be brownish, 



but never yellow. 



14 (15). Usual bristles on the mid and hind tibiae very faint; 



fore coxae dirty whitish. (1265. cupreus, Mcq.) 



15(14). Usual bristles on mid and hind tibiae conspicuous; 

 fore coxae not dirty whitish. 



16 (17). Face of male dull pale green ; eyes narrowly separated ; 



antennae large. (1269. amplicomis, Ztt.) 



17 (16). Face concealed by the touching eyes; fore and hind 



tibiae considerably ciliated. 



(1264. blepharosceles, Kow.) 



18 (13). Legs considerably yellow on at least the fore and 



mid tibiae. 



19 (20). Mid tibiae with only one distinct bristle; very small 



species. (1271^. monochcetus, Kow.) 



20 (19). Mid tibiae with the usual two bristles, the lower one 



being very small. 



21 (22). Third antennal joint small and rounded ; hind tibiae 



reddish; small species. (1271. mtcrocerus, Kow.) 



22 (21). Third antennal joint not very small ; hind tibiae 



blackish in the male ; not very small species. 



23 (24). Third antennal joint moderately rounded, colour 



bright. 



1270. Chrysotus grantineus, Fin. 

 Hesleden, 1 ?, August, 1900. 



24 (23). Third antennal joint angulated at the tip; colour 



dark. (1266. angitlicomis, Kow.) 



