140 NORTH AMERICAN IMPTERA. 



'A. Alxlonien witli botli diseal iind margiiuil inaLTocliictiu on tlie second and 

 following- segments. -f- • ■ Paramintho Wulp. 



Abdominal segments witli dist-al macroclifeta'. . . . . o 

 8. First longitudinal vein bristly. . . Jounsonia Coquillett. 



First longitudinal vein not bristly. S akcopiiilodes Brauer and Berg. 



4. Abdomen blaek or metallic, unicolorous and but slightly pruinose. o 

 Abdomen gray, cinerous or partly ochraceous, with black reflecting 



spots. ........... 7 



5. IIypoi)ygium very prominent ; legs more or less hairy. . . (J 

 Hypopygium concealed ; legs not hairy; abdomen metallic; curvature 



of fourtli vein witli an obtuse angle and without stump. 



Onesia Desvoidy. 



6. Abdomen usually black; tibias densely hairy. Piiuissopoda Macquart. 

 Abdomen metallic; tibiaj with short hair. Cvnoaiyia Desvoidy. 



7. All the tibia^ on tiie outer side with a comb-like row of long, stout 



bristles. ........ Thekia Desvoidy. 



Tibiaj without bristles or with irregularly placed ones. ... 8 



8. Apical oross-vein more oblique than the posterior one. ... 9 

 Apical and posterior cross-veins in nearly the same line; two orbital 



bristles in the 9. none in the $. . . Sarcophaga Meigen. 



9. Two orbital bristles in each sex. . . . Sarcophagula Wulp. 

 Two orbital bristles in the ?(<??) • . Helicobia Coquillett. 



r>o. MUSCID.^. 



Ratlier small to moderately large, never elongate, thinly 

 hairy or bare flies. Antenna! arista plumose to the tip; some- 

 times above only, and rarely bare, in which cases the absence 

 of bristles on the abdomen, except at the tip, together with 

 the distinctly narrowed tirst posterior cell, characters distinc- 

 tive of the grouj), will distinguish the flies belonging here 

 from its allies. Eyes of the male approximated or contigu- 

 ous ; front of female broad. Eyes bare or hairy. Abdomen 

 composed of four visible segments. Genitalia not prominent. 



Like the Sarcophagidse, the species and individuals of this 

 family are common everywhere. The common house-fly, the 

 ty})e of the group, has a cosmopolitan distribution wherever 

 man exists. Other species, which are scarcely less common 

 and widfdv distributed, are the cninnion blno-bottle and blow- 



