24,2 [October, 



FEMALES.* 



1. Abdomen witii sides of two or three basal segments yellow... 



16. curvipes, Fin. 

 Abdomen nowhere yellow 2 



2. Head of halteres yellow 3 



Head of halteres black or dark brown 5 



3. Thorax and abdomen shining blue-black; front tibiae with a postero-ventral 



bristle at one-tliird from apes 1. ciliata, Fah. 



Thorax and abdomen yellowish-grey or brownish-grey ; front tibioe witliout 

 postero-ventral bristle 4 



4. Arista distinctly pubescent ; posterior transverse vein nearly straight, more 



tlian its own length from the middle transverse vein ... 15. irritans, Fin. 



Arista practically bai-e ; posterior transverse vein strongly flexed, not more than 



its own length f?om the middle transverse vein 9. albipuncta, Ztt. 



5. Middle tibise with an anterior bristle 6 



Middle tibise without anterior bristle 11 



6. Middle tibioe with a ventral bristle 10. niilitaris, Mg. 



Middle tibiae without ventral bristle 7 



7. Front tibise with a median dorsal bristle 8 



Front tibiffi without median dorsal bristle 10 



8. Thorax yellowish-grey, with a more or less distinct central stripe... 



6. palivsfrica, Mg. 



Thorax blackish, with slight grey tomentum and four (two broad outer and two 

 narrow inner) rather indistinct stripes 9 



9. Hind tibiaj with two, rarely three, antero- ventral bristles ; calyptra whitisli... 



4. dentipes, Fab. 



Hind tibiae with four to six antero-ventral bristles ; calyptra more or less tinged 



with yellow 5. sim His, Meade. 



10. Size larger (6 mm.) ; calyptra strongly tinged with yellow ... 7. pilipen, Stein. 

 Size smaller (3 — 4 mm.) ; calyptra without trace of yellow... 18. ^ar«a, Meade. 



11. Abdomen shining black or blue-black, with scarcely a trace of tomentum ... 12 

 Abdomen more or less covered witli grey tomentum 13 



12. Frons all shining black ; size smaller (3 mm.) 17. glabricula, Fin, 



Frons dull black, with a little grey tomentum ; size larger (4 — 5 mm.)... 



11. tuherculata, Rond. 



13. Ocellar triangle black and conspicuously polished 2. occulta, Mg. 



Ocellar triangle dull greyish, or at any rate never conspicuously polished ... 14 



14. Hind tibiae with four to five antero-ventral bristles 3. cyrtoneurina, Zit. 



Hind tibiae with at most two antero-ventral bi'istles 15 



15. Thorax shining black, with very little tomentum ; size larger (5 — 7 mm.)... 



12. velutina, Dsv. 

 Thorax thickly covered with grey tomentum ; size smaller (5—5^ mm.) ... 16 



16. Arista distinctly pubescent ; hind tibiae with three bristles about the middle... 



13. meteorica, L. 

 Arista quite bare ; hind tibise with only two bristles about the middle... 



8. armipes, Fin. 



* As the female of H. cinerea, Dsv., is not known to either Herr Stein or myself, I have not 

 been able to include tliis species in the present key. 



