.1 Monograph of Egyptian Dipt era. 1 ( > 



US. 



22 (23) Frons inflated (PL I, fig. 11) 10 Lasiophthic 



23 (22) Frons normal. 



24 (25) Thorax provided in front with a 



distinct collar of hairs; ocelli at some 



distance from the vertex 11 Asarcina.* 



25 (24) Thorax without a distinct collar of 



hairs; ocelli placed near the vertex. . 12 Syrphus. 



2(3 (15) Abdomen conspicuously constricted 

 about the base, tubular and club-shap- 

 ed; markings less well defined 13 Pseudodoros. 



27 (2) Radio-median cross-vein placed after 



the middle of cell M2. 



28 (35) Radius 4 + 5 looped causing cell R5 to 



be remarkablv contracted about the 



middle " (ERISTALIN^F) 



29 (30) Radius 1 united with Radius 2 + 3 at 



the end, (PL I, figs. 1, 2) 14 Eristalis. 



30 (29 Radius I separated from Radius 2 + 3. . 



31 (32) Hind femora with a distinct tooth-like 



process beneath, near the apex 15 Merodon. * 



32 (31) Hind femora not toothed. 



33 (34) Eyes hairy 16 Myiatropa* 



34 (33) Eyes bare 17 Helophilus. 



Subgenera : — 



1 (2) Eyes of male almost 



touching Mesembrius. 



2 (1) Eyes of male widely 



separated 



*So far not represented in Egypt. 



