62 Key to Families of North American Insects. 



5. Mesonotum without a transverse suture; second vein strongly arched forward. 



(Dixa) DIXID^E 



Mesonotum with a more or less distinct suture; female with a conical ovipositor. 

 Crane-flies, Daddy-long-legs 7 



6. Wings ovate or pointed, held folded roof-like against the body, veins very hairy; 



tibiae without terminal spurs; small species. Moth-flies. (Psychdda, 



Pericoma) (PI. 12, fig. 263) PSYCHODHX& 



Wings narrow, not thus folded against the body; veins scaly; tibia? with terminal 

 spurs; antennae of the males usually feathered with long hairs. Mosquitoes. 

 Culex [C. quinquefasciatus, Dengue-fever and Filaria mosquito], Aedes 

 [A. calopus(Stegomyiafasciata), Yellow-fever mosquito], Anopheles [A. 

 quadrimaculatus, Malaria mosquito]) (PL 12, fig. 267) CULICID./E 



7. Suture of mesonotum distinctly V-shaped; two anal veins present 8 



Mesonotal suture not distinctly V-shaped, but incomplete or curved; one anal 



vein present. (Bittacomorpha, Ptych6ptera) (PL 12, fig. 269) (LIRI- 

 OPEIDM) PTYCHOPTERmE 



8. Last joint of palpi whiplash-like, much longer than the three preceding together; 



antennae with rarely more than thirteen joints; auxiliary vein ending in the 

 first vein by an abrupt curvature at the tip, not connected with the first 

 by a crossvein. (Tipula, Pachyrhina, Cten6phora) (PL 11, fig. 240; PL 



12, fig. 273) TIPULIDyE 



Last joint of the palpi shorter or not much longer than the two preceding to- 

 gether; antennae six- to sixteen-jointed, rarely more; auxiliary vein usually 

 ending in the costa and connected with the first vein by a distinct crossvein. 

 (Limndbia, Eri6ptera, Limn6phila, Trich6cera) (including CYLINDRO- 

 TOMHXE) LIMNOBmXE 



9. Antennas composed apparently of two joints and a terminal nine- or ten-jointed 



arista; a small but broad second basal cell present; rare small species. 



(Orphnephila) (PI. 12, fig. 284) ORPHNEPHILHX 



Outer part of the antennae not formed like an arista; second basal cell absent, 

 or, if present, narrow 10 



10. Wings with a secondary neuration like a fine network of creased lines; slender 



long-legged species. (Bibiocephala, Blepharocera) (PL 12, fig. 277) 



(LIPONEURIDM) BLEPHAROCERID^ 



Wings without such secondary neuration 11 



11. Second basal cell present; antennae usually shorter than the thorax, rather 



stout, without constrictions between the joints; eyes of the male often large, 

 ocelli almost always present. (Bibio, Dflophus, Plecia) (PL 11, fig. 241; 



PL 12, fig. 266) (including PACHYNEURIDM) BffilONID^E 



Second basal cell wanting 12 



12. Antennae shorter than the thorax, rather stout, composed of ten or eleven 



closely united joints, never feathery; eyes of males meeting above; body 

 stout, legs strong; anterior veins strong, posterior veins weak. Buffalo- 

 gnats, Black-flies. (Simulium) (PL 11, fig. 243; PL 12, fig. 272) (MEL- 



USINIDJE) SIMULIID^ 



Antennas long and slender, the joints longer than broad, rarely (Ceroplatus) 

 the antennae are flattened; body slender IS 



