488 Annals <>f the tividli African 



the cubitus of the 4th nervure often with a weak umbrate line. The 

 distinctive characters are : the minute anterior claws in the $ , and the 

 presence of 2 + 2 sternopleural setae. Abdomen without discal setae. 

 Antennae very long, robust, covering the whole of the epistome ; 2nd 

 joint very short, 3rd 7 to 8 times as long as the 2nd ; antenual chaeta 

 much elongate ; 2nd joint distinct ; 3rd joint thickened in the basal 

 third, thence slender. Erect, equal, moderately long vibrissae ascend 

 above the great one as far as the centre of the facial ridges. 



PROZENILLIA DISTANS, n. sp. 



Black, moderately brilliant on the abdomen ; segment 2 with a light 

 ashy anterior band interrupted in the centre and obliterated before 

 reaching the sides ; segment 3 with a similar band, but wide and nearly 

 entire, being incised in the centre only ; segment 4 wholly shiny black ; 

 2 median marginal setae on the two basal segments. Scutellum with 4 

 marginal setae, the apical moderately developed and crossed. Colour 

 of thorax and head same as in the preceding species, the first with 4dc. 

 Frons wider (width equal to -f of the distance from the eye to vertex 

 in the $ ) ; 1 outer vertical seta ; 1 long, ascending inner vertical seta ; 

 2 ascending frontal on each side, and a pair of ocellary setae thrusting 

 forwards and equally long and robust ; 3 frontal setae somewhat spaced 

 below the insertion of the antennae and plainly descending lower than 

 the chaeta. Upper occiput with small black setae at the back of the 

 ciliae. Antennae and palpi black, the latter arcuate and thickened at 

 end. Legs black ; hind tibiae ( $ ) with a row of moderately closely 

 set setae which at first increase from above to below, then regularly 

 diminish in length, this row has a longer seta in the centre. Wings 

 with pale nervures at base ; cubitus of the 4th nervure straight or a 

 little obtuse ; apical transverse nearly straight and moderately oblique, 

 posterior transverse, slightly flexuose, removed from the angle. Costal 

 spine absent ; 2 strong ciliae at the base of the 3rd nervure. Squamae 

 whitish with a yellowish slender border ; halteres testaceous, club 

 blackish. 



Natal, Durban (H. W. Bell-Marley), S. Afric. Museum. 



CHAETOLYDELLA, u. gen. 

 Fig. 3. 



Facies of the genus Lydella E. D., owing to its elongated and 

 cylindrical shape ; wing with the cubitus of the 4th nervure at right 

 angle or subacute, and provided with a long prolongation as in 

 Tacliina Meig. ; 3rd nervure ciliated to near the small transverse. 



