192 DURHAM DIPTERA. 



XXVIII. 288. 



60 (59). Abdominal spots reaching the side margins. 



(1537. triangulifer, Ztt.) 



61 (58). Antennae with the third joint blackish, except at the 



base ; scutellum black haired. 



62 (63). Abdominal spots triangular ; eyes bare. 



1535. Syrphtis auricollis, Mg., var. maculicomis, Ztt. 

 Hesleden, 1 $, i ?, 31-8-98. 



63 (62). Abdominal spots semicircular ; eyes slightly hairy. 



(1538. pwictulatus, Verr.) 



64 (57). Antennae entirely blackish. 



65 (66). Face and frons entirely yellow. (1539. guttatus, Fin.) 



66 (65). Face with a black middle line ; frons partly black. 



67 (72). Jowls yellowish, the dark middle facial line short, not 



extending beyond the facial knob. 



68 (69). Thorax shining; fore and mid tibiae all yellow except 



a slight dark ring ; vertex deep blue in the female. 

 1540. Syrphus umbellatarum, F. 

 Hesleden, 1 ?, 28-8-99. 



69 (68). Thorax dull ; legs black with yellowish knees. 



70 (71). Thorax dullish ; female frons and vertex black. 



1 541. Syrphus compositarum, Verr. 

 Hesleden, 3 ? , August, 1899; locality uncertain, 1 ?. 



71 (70). Thorax very dull ; female frons and vertex grey ; 



wings brownish. 



1542. Syrphus labiatarum, Verr. 

 Hesleden, 1 $, 18-8-02. 



72 (67). Jowls blackish ; dark middle facial line extending to 



antennae. 



73 (74). Eyes slightly hairy ; male abdominal basal spots not 



extra small. ( I 543- lasiophthalmus, Ztt.) 



74 (73). Eyes bare; male abdominal spots small or absent; 



face in male almost all black. 



75 (76). Abdominal spots very small ; halteres dark. 



(1544. arcticus, Ztt.) 



76 (75). Abdominal spots absent ; halteres yellow. 



(1545. barbifrons, Fin.) 



