Platychirus. 191 



more æneous and hoary spots on abdonien (melanoid specimens may 

 occur). Head somewhat semiglobular, generally a little broader than 

 high, and a little broader than thorax; it is somewhat excavated 

 behind. Eyes touching in the male, separated in the female; they are 

 bare, the facets in the male a little enlarged in the upper part. An- 

 tennæ inserted well above the middle; they have the third joint gener- 

 ally a little longer than broad, oval or more square; arista inserted 

 near the base, thickened in about the basal half, with two quite small 

 basal joints; the basal antennal joints have small bristles at the end 

 margin, the third joint and the arista are microscopically haired. The 

 epistoma has a central knob, and the upper mouth edge may be a 

 little produced; the lower part of epistoma with the central knob may 

 be more or less produced, in some species rather strongly, or epistoma 

 may be rather tlat with only the central knob a little protruding. At 

 the lower eye-margin there is a furrow, somewhat separating epistoma 

 from the jowls, but not reaching up to the central knob. Epistoma 

 is black but more or less covered with dust, and it is thinly haired 

 on the side paris with erect hairs. The oral aperture larger or smaller 

 in accordance with the epistoma being more or less protruding; when 

 protruding the front ends of the lateral mouth edges, the lateral 

 angles, are drooping and the front mouth edge somewhat excised. 

 when the epistoma is more flat the mouth aperture is simply rounded 

 a little upwards in front. The jowls only slightly descending. Oral 

 cone well developed ; clypeus of usual shape, with a basal part and 

 two long, thin legs. Proboscis somewhat long; labrum {albimanus) 

 strongly semitubular, the apical processes of nearly equal length, the 

 median cleft at the end, with the apices diverging and divided into 

 several pointed branches; the upper lateral processes thin and delicate. 

 the lower broad with the apex rounded and curved a little upwards; 

 the lateral margin of labrum bears below a row of small papillæ or 

 warts. Hypopharynx a little shorter than labrum, semitubular, linear 

 and slightly attenuated outwards with rounded apex, and with a 

 distinct salivary duet. Maxillæ with a slightly curved, knife-shaped 

 lacinia, and long, thread-like palpi with the end clubbed; the palpi 

 are densely clothed with short hairs and have some bristles on the 

 clubbed end part; the lacinia is beset with microscopical spines in 

 longitudinal rows about as in Chilosia. Labium has the chitinised 

 basal part somewhat narrow, longer than the oval labella. Thorax 

 rectangular, at the upper end of the præsutural depression is a small 

 tubercle. Scutellum æneous, not pellucid, below its margin a fringe 

 of hairs, directed downwards. There are no bristles present. Meta- 

 pleura densely short-haired. Abdomen elongate, rather narrow and 



