32 



THE DIPTERA 



A. Proboscis long, adapted for biting — PhilcBmatomyince. 



I. Proboscis partly chitinous, partly fleshy, with large 

 fleshy labellae. — PhilcBmatomyia. 

 II. Proboscis entirely chitinous, with attenuated labellae — 

 StomoxyMncB. 



(a) Arista feathered dorsally only. 



{a) Palpi thin, much shorter than the proboscis. 

 Third longitudinal vein with bristles proxi- 

 mally; first posterior cell open — Stomoxys. 

 {b) Palpi thickened, as long as or nearly as long as 

 the proboscis. 

 ^ (i) Proboscis long and tapering; first posterior 

 cell widely open; third longitudinal vein 

 without bristles — Lyperosia. 

 (2) Proboscis short and stumpy; first posterior 

 cell narrowly open; third longitudinal vein 

 with bristles proximally — Stygeromyia. 

 (c) Palpi strongly built everywhere, not thickened. 



Proboscis thin, more than twice the head 

 length, swollen at the base. Arista with 

 many branched hairs. Media (fourth longi- 

 tudinal) with two sharp bends — Glossina. 



(b) Arista feathered dorsally and ventrally. 



[a) First posterior cell narrowly open; third longi- 



tudinal vein without bristles — Hcsmatohosca. 

 [h) First posterior cell widely open. 



(1) Third longitudinal vein with bristles proxi- 



mally — Hc&matohia. 



(2) Third longitudinal vein without bristles 



proximally — Bdellolarynx. 



B. Proboscis short, not adapted for biting — Muscince. 



(a) Mid-tibia without bristle on inner side — Musca, 



(b) Mid-tibia with bristles on inner side. 



(1) Thorax and abdomen bluish-black, not lustrous — 



Calliphora. 



(2) Thorax and abdomen green or greenish, lustrous. 



{a) Scutum longitudinally marked — Chrysomyia. 



(b) Scutum not so marked. 



(a) Thorax metallic green or bluish-green — 



Lucilia. 



(b) Thorax brassy green or purplish-blue — 



Pycnosoma. 



(3) Thorax and abdomen dirty brownish-yellow. 



(a) Eyes wide apart in both sexes, second abdominal 



segment of the female more than half the length 

 of the abdomen — Auchmeromyia. 



(b) Eyes of male not wide apart, and second abdo- 



minal segment without the above character — 

 Cordylobia, 



