20 THOMAS SAY FOUNDATION 



6. Arista sliort-jilimiose 7. 

 Arista loiig-pluiuose 10. 



7. Parafaeial witli a single inac-rocliaeta below, pro- 



cliiiate (Louisiana, Texas) 



Camptopijga n. g. 

 Parafaeial with a row of hairs. 8. 



8. No costal spine (widespread north) 



A grid Desvoidy. 

 Costal spine strongly developed 1). 



9. Back of head with only black hair; anterior 



acrostichals very large (northeastern) 



Harhcckia n. g. 

 Back of head with some pale hair; no ant acr 

 (widespread) Hijpopclta n. g. 



10. Two large posterior dorsocentrals, two equally 



large anterior ones (tropical) 



Notochcvta n. sp. 

 Generally three or four ps dc, if only two the 

 anterior ones are much reduced 11. 



11. Vibrissa^ approximated and high above the oral 



margin (the distance ecpialing the length of 

 the second antennal joint) (widespread) 



Emblem (ISO ma n. g. 

 Vibrisste normal, or if somewhat approximated 

 they are not strikingly removed from the 

 oral margin 12. 



12. Parafacials quite bare; first vein hairy (Louis- 



iana) Sthcnopi/ga n. g. 



Parafacials M'ith hairs, sometimes delicate. 1.3. 



13. Ocellars absent; frontal rows not noticeably di- 



vergent below% reaching base of antennae 

 (tropical) Harpagop/jga n. g. 



Ocellai's present; if absent, the frontal rows are 

 abruptly divergent below and reach a])out 

 to the middle of second antennal joint 14. 



14. Fifth sternite of male undivided; epaulet yel- 



low; back of head with only black hair 

 (northeastern) Thclodlscus n. g. 

 Fifth sternite of male dee])ly divided (wide- 

 spread) Sarcophaga Meig. 



