170 DURHAM DIPTERA. 



XXVIII. 



57 (58). Frons inflated. Catabomba, O.-S. (287) 



58 (57). Frons not inflated. 



59 (60). V.3 2 much looped, as in (V. 20). Didea, Mcq. (286) 



60 (59). V.3 2 not, or not much looped. Syrphus (288) 



61 (3). 0.2. closed. Arista very plumose (III. 43). Profile 



(VI. 15). 



Sub-Family Volucellin^e. 



299. Volucella, Geoff. 



62 (2). X.4. at or after the middle of O., i.e., V.4 2 as long as, 



or longer than V.4 3 (V. 19, 20). 



63 (74). V.3 2 bent in a distinct loop (V. 20). 



Sub-Family Eristalin^e. 



64 (65). 0.2. closed (V. 20). Eristalis, Ltr. (300) 



65 (64). 0.2. open. 



66 (71). Hind femora without any tooth-like process beneath 



near the tip. 



67 (68). Eyes hairy. Myiatropa, Rnd. (301) 



68 (67). Eyes bare. 



69 (70). Thorax very hairy. 



303. Malotta, Mg. (1588. cimbiciformis, Fin.) 



70 (69). Thorax almost bare. Helophilus, Mg. (302) 



71 (66). Hind femora with a distinct tooth-like process. 



72 (73). Eyes hairy. Very hairy species. 



Merodon, Mg. (304) 



73 (72). Eyes bare. Body almost bare. 



305. Tropidia, Mg. (1590. scita, Harr.) 



74 (63). V.3 2 not, or not much looped. 



Sub-Family Milesin^e. 



75 (78). Arista plumose. 



76 (77). Very hairy species, without yellow abdominal bands. 



Arctophila, Schin. (316) 



77 (76). Thinly hairy species, with yellow abdominal bands. 



Sericomyia, Mg. (317) 



78 (75). Arista bare. 



79 (86). Very hairy species. 



