393 



— At least the penultimate and antepenultimate segments with dorsal 



transverse series of short thorns; slender hairs interspersed be- 

 tween the short thorns on all segments 10 



10. Wings extending to apex of third abdominal segment, their color 



pale SystoecJius oreas. 



— Wings extending short of apex of second abdominal segment, 



fuscous apically Exoprosopa fasciata? 



11. Transverse armature of first abdominal dorsal segment consisting 



of a series of short, stout thorns on middle portion, and a number 



of long, slender, closely placed hairs on each side 



Exoprosopa fascipennis. 



— Transverse armature of first abdominal dorsal segment consisting 



of a few widely placed hairs, the middle portion either entirely 

 bare or with very slight indications of small tubercles which do 

 not appear as distinct thorns 12 



12. Lower one of the pair of lateral cephalic thorns simple apically, but 



with a small wart-like protuberance at base on lower surface, the 

 small wart bearing 2 distinct hairs; wings without discal protu- 

 berances Sparnopolius fulvus. 



— Lower one of the pair of lateral cephalic thorns with a short sub- 



apical protuberance, the apex of thorn turned upward, base sim- 

 ple ; wings each with a pair of protuberances, one about one fourth 

 from base and the other near middle AnastoecJius nitidulus. 



13. No Avell-developed pair of thorns on lower median portion of face. . 



ToxopJiora virgata. 



— A well-developed pair of thorns on lower median portion of face . 14 



14. Eighth ventral abdominal segment without hairs on disc 



HyalantJirax 7iy pomelos. 



— Eighth ventral abdominal segment with hairs on disc 15 



15. Eighth ventral abdominal segment with 2 hairs on each side of disc : 



distance from the pair of thorns on lower central portion of head 

 to apex of basal portion of sheath of mouth-parts about 4 times 



as great as distance from the latter to apex of proboscis 



Hyalanilirax lateralis. 



— Eighth ventral abdominal segment with 10-12 long hairs on disc; 



distance from the pair of thorns on lower central portion of head 

 to apex of basal portion of sheath of mouth-parts about twice as 



great as distance from the latter to apex of proboscis 



HyalantJirax alternata. 



Spogostylum simson Fabrlcius 



Anthrax simson Fabricius, Syst. Antl., p. 49. (1805) 



Spogostylum sivison (Fabricius) Wieclemaiin, Dipt. Exot., Vol. 1, p. 122. (1821) 



Ptipa. — Length, 20 mm. Brownish testaceous, slightly shining; 

 cephalic and abdominal thorns dark brown. 



