138 ENTOMOLOGY FOR MEDICAL OFFICERS 



(■Abdomen short, stout, very convex 

 g J = Stibasoma, Schiner (America). 



lAbdomen not as particularised in Stibasoma = lo. 



(-Antennae long and slender, the ist segment long 



10. -' = Acanthocera, Macquart (South America), 



I Antennse not as particularised in ^C3«^/44>f«ra: = ii. 



f Slenderer in build, usually with thorax and abdomen banded ; 3rd 

 antennal segment slender, wings mostly with brown mark- 



11. -! ings = ZJ/V^^/a^nz, Macquart (South America). 

 I Stouter in build, 3rd antennal segment stout 



= Tabanus, L. {sensu lat.). 



2. Pangoniina. 



(Third antennal segment composed of 8 or 7 subsegments or rings ; 

 proboscis usually elongate = 2. 



Third antennal segment composed of 5 rings ; proboscis short 

 = 14. 

 /Third antennal segment with a tooth Dicrania, Macquart (Brazil). 

 I Third antennal segment with no tooth = 3. 



/Wings short ; body flat, elliptical Apocampta, Schiner (Australia). 

 \ Wings not short = 4- 



(■Third antennal segment with each subsegment branched 



4. \ Pityocera, Tos (Central America). 

 iThird antennal segment not branched = 5. 

 (■Upper corner of eye terminating in an acute angle 



5. J Goniops, Aldrich (North America). 

 lUpper corner of eye not terminating in an acute angle = 6. 

 (■Antennae deep-seated, inclined downwards ; palpi very large 



6. \ Cadicera, Macquart (South Africa). 

 I Antennae and palpi not as particularised in Cadicera = 7. 



(Antennas awl-shaped ; end of proboscis hatchet-shaped ; anal cell 

 open and anal vein curved 

 Pelecorhynchus, Macquart (Australia and South America). 

 Antennje, proboscis, anal cell, etc., not as in Pelecorhynchus = 8. 

 (■Proboscis scarcely extending beyond palpi 

 8. \ Apatolestes, Williston (California). 



I Proboscis extending beyond palpi = 9- 



/Wings with 4th posterior cell closed = lo. 



I Wings with 4th posterior cell open =11. 



/Eyes bare Dorcalamus, Austen (South Africa), 



t Eyes not bare Scione, Walker (South America, Seychelles, Australia). 

 /Wings with ist posterior cell closed = 12. 



I Wings with ist posterior cell open =13. 



J 2 /Eyes bare Pangonia, Latr. (subgenus Pangonia). 



I Eyes hairy Pangonia, Latr. (subgenus Erephrosis, Rond.). 



(■Eyes hairy Diatomineura, Rond. (subgenus Diatomineura). 



13. \ Eyes bare 



I Diatomineura, Rond. (subgenus Corizoneura, Rond.). 



