868 REPORT OF THE HARVARD AFRICAN EXPEDITION 
bo 
Or 
30. 
2. Eyes bare in both sexes. Third antennal segment not crescent-shaped. Frons in the 
female as a rule with a distinct basal callus.............-2--2- eee eereeene Stlvius. 
Eyes pubescent in both sexes (often slightly so in the female). Third antennal segment 
more or less crescent-shaped. Frons in the female with or without distinct basal 
Gallas ans Se ermsrate este eich alata ki eye am aie eae Mesomyia. 
. Antennae placed on the lower part of the head and directed downward. Face convex 
below the antennae in the female. Palpi large and swollen. Eyes bare. Ocelli 
absent (rarely with anterior ocellus). Proboscis of moderate length. First posterior 
cell as a rule closed and long-petiolate (in some species more or less open); fourth 
posterior cell open (very rarely closed). Fore tarsi of male without appendages. Phara. 
Antennae not placed on the lower part of the head and not directed downward. Palpi 
Sonal artgeslemo Obese c sch Pace wattle bia oe ataee anne Ore ake ake ee ee eee eo 24. 
. Proboscis thick and only a little longer than the head, ending in two very large, blunt labella, 
which take about half the total length of the proboscis and are provided with rod- 
like processes on the inner surface. Ocelli absent. Eyes bare. First posterior cell 
closed and long-petiolate; fourth posterior cell open; fork of third longitudinal vein 
WLU AM Ap PRN Glsomewe i. kw w Rene eerety ie goes eee ee eae eee Subpangonia. 
Proboscis slender and often longer than the head, ending in narrow labella without rod- 
MEG rOCESSOS) . Poutes Seg os 24.5 55 SEs tee Meee oe ee ee Cee eee 25. 
. First posterior cell closed and long-petiolate. Fork of third longitudinal vein with ap- 
pendrx, Rivesshare:- .Ocellabsentied scx ctsck os he ee oe ee ee ee eee 26. 
First posterior cell open or rarely closed just at the hind margin of the wing.......... 28. 
Fourth posterior cell closed and long-petiolate. Wings relatively short and broad, bluntly 
rounded at the tip. Face of female convex beneath the antennae, but not produced 
into a long snout. Fore tarsi of male without appendages.............. Dorcaloemus. 
Fourth posterior cell open or rarely closed just at the hind margin of the wing......... 27. 
. Face strongly swollen beneath the antennae and produced into a snout, often with shiny 
callosities. Fore tarsi of male as a rule with lappet-like processes at the apices of the 
fireshand second seomentey 7. 2s. ccs ee be © isauee ae Ce Seen Philoliche. 
Face merely convex beneath the antennae, not produced into a snout, as a rule without 
shiny callosities. Fore tarsi of male without appendages................ Stenophara. 
. Eyes pubescent. Ocelli present. Proboscis short or of moderate length. Face convex 
beneath the antennae, not snowtlike. 2. ..40. 22. ese aete ons eae eee eee Scaptia. 
| ya 022 4 2 a Car a aS ee a oe AE ee ory al Bs a A 29. 
. Ocelli present. Face convex beneath the antennae, not snout-like, without shiny areas or 
calli. Proboscis of moderate length, rarely longer than the thorax. Fore tarsi of 
iDAle Withombrmappendages. 2.0.01, sss eee = wee wee Oe Naren ree oe Buplex. 
Weel alo serities esate since os 5 occ She Ce wep Se Oe ous oom SRN cI a ee cre 30. 
Face convex beneath the antennae, not snout-like, without shiny areas. Proboscis of 
moderate length, rarely longer than the thorax. Fore tarsi of male without append- 
LCS es ah Merete ese vis oa Vis heats ees Ore ee eee eee ae Ommatiosteres. 
Face very prominent and more or less snout-like beneath the antennae, as a rule with 
shiny areas or calli. Proboscis of variable length, often much longer than the thorax. 
First and second segments of fore tarsi in male often produced at the apex into 
FON AUS OF lA pPer Re PrOCesseSiA.. ss. s k A i ven e ek eee ee Ce eee ee Nuceria. 
SUBFAMILY PANGONIINAE 
Tribe Pangoniini 
Silvius Meigen 
Silvius Meigen, 1820, ‘Syst. Beschreib. Europ. Zweifl. Ins.,’ II, p. 27. Monotypie for Tabanus 
vituli Fabricius, 1805. 
Perisilvius Enderlein, 1922, Mitt. Zool. Mus. Berlin, X, 2, p. 344; 1925, loc. cit., Al, 2, p. ollb. 
Monotypic for Perisilvius nyasstcus Enderlein, 1922. 
The species generally placed in Szloius up to Enderlein’s time certainly 
formed a heterogeneous group. Two of the genera accepted or proposed by 
