549 



Family RHYPHID^. 



Flies of moderate size, or small, with an appearauce partakinc; 

 of that of the Tipuhd.i;, as well as of the MYCETOPiiiLiDiE. 

 Head hemispherical, eyes rounded, contiguous in male and wide 

 apart in female (in lihyphus) ; in one genus * the frons is wide in 

 both the sexes. Ocelli present. Proboscis moderately prominent 

 (Rhyphus) or hardly at all prominent {Olbiotjaster) ; labella small. 

 Palpi 4-jointecl, rather long (lihifphus), or short {Olbiog aster). 

 Antennae about as long as the thorax, 16-jointed, the two basal 

 joints differentiated ; the flagellum in lihyphvs composed of com- 

 pact annular or cylindrical joints placed I'ather closely together, 

 whilst in Olhiogaster, a Mexican genus, the flagellar joints in the 

 male are filiform. Thorax without transverse suture, oval, arched ; 

 scutellum transverse, moderate in size ; metanotum well developed. 

 Abdomen flattened, cylindrical, seven-segmented ; genital organs 

 hardly prominent. Legs moderately long anel slender ; tibiae 

 without terminal spinas, or the hind pair sometimes with minute 

 ones; pulvilli absent, empodium pulvilliform. Wings compara- 

 tively large and broad, folded over the abdomen, wheu in repose ; 

 in most species they are faintly marmorated or marked with pale 

 grey and darker brown spots ai;d short bands. Auxiliary vein 

 present ; 2nd longitudinal vein simple, discal cell always present ; 

 4th vein with both its upper and lower branches forked ; 5th, 6th 

 and 7th veins distinct, long, the latter moderately abbi'eviated. 



The family is represented in Europe, North and South America, 

 West Africa, the Orient, Tasmania and New Zealand. 



The EHYPHiDiE, as compared with the other families of 

 Nematoceba, except many Tipulid^b, are distinguished by the 

 presence of the discal cell in the wings ; the Tipulid.e, in which 

 it is normally and generally present, being the only other family 

 in this suborder possessing it. In addition the present family 

 has a peculiar venation, which in some respects appears as if it 

 were related to that of the LeptidyI;, amongst the Bkachycera. 

 The resemblance is further heightened by an apparent affinity 

 between the antennae of Rhyphus and those of one or two genera 

 of Leptid.e, Xylopihagus for example; but the student may at 

 once distinguish between the two by the shape of the anal cell, 

 which in E.HTPHID.E is wider towards the posterior margin, whereas 

 in Leptib.e it is much narrowed distally or actually closed. 



* Olbiogaster, Os. Sac, a non-Orieatal genus, to which is aUied a very 

 similar one, Lobogaster ; these three genera comprising the whole of the 



EiIYI'IIIDjE. 



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