1921.1 _ 247 



bristles holutid; hind femora with 4-o stoutish anternventral bristles 

 on apical half but comparatively short-haired posteroventrally. 

 Wings rather more tinged with brown than in allied species. 

 Squamae whitish-yellow. Halteres yellow. 



2 . Thorax lighter brown than in male, but still most incon- 

 spicuously striped compared with allied species. In front of suture the 

 narrow median and broad side stripes can be traced, while in addition 

 two narrow browuish-grey stripes are present right on the front cf 

 thorax and continued between the acrostichal and dorsocentral rows 

 of bristles faintly to suture. Abdominal browniah patches large 

 but not very sharply diiferentiated from the ground-colour; those 

 on second segment the longest and broadly extended along the hind 

 margin towards sides. Legs as iu the male, but hind femora quite 

 short-haired posteroventrally. 



Length 5 mm. 



This species is known to me as British from a single male only, 

 taken by Col. Yerbury at Aviemore (Inverness) on June 15th, 1913, 

 but I possess a pair of Swedish specimens through the generosity of 

 my friend Herr 0. Riugdahl of Halsingborg, 



Suhf/enus Calliophhys. 



1 (2) Face narrower and vibrissal angles silvery like the face. Frons not 



wider at base of antennae than at vertex, and when viewed from in 

 front with at least half the width about middle with a light 

 brownish- or yellowish-grey sheen 



.... 2-8. exuta Kow. 



J. The greyish sheen on frons is much less conspicuous than in 

 riparia and only visible when viewed right from in front. Inter- 

 frontaUa not so sharply differentiated. Eyes rather larger. Face not 

 so sharply produced atmouth edge. Antennae narrower. The narrower 

 face is chiefly due to the facialia being noticeably narrower than in 

 riparia. Thorax more uniformly brownish without indications of 

 the grey lines between acrostichals and dorsocentral usually present 

 in riparia. Three or four pairs of postsutural dorsocentral bristles. 

 The species in other respects much resembles riparia. 



$ . Very much like the male. Thorax occasionally with indica- 

 tions of narrow grey stripes. Abdominal patchts rather more 

 shining than in the male. 



Length 4-5 mm. 



This species has been found by Mr. Verrall at Dawlish (Devon) 

 and Dovedale (Derby) in June, at Windermere (Westmorland) in 

 July and at Mildenhall (Suffolk) in September. Col. Yerbury has 

 caught it at Barmouth (Merioneth) in July and as far north as Loch 

 Assyut (Sutherland) in June. 



2 (1) Face wider and vibrissal angles darkened. Frons rather wider at base 



of antennae than at vertex, and when viewed from in front with 

 only the middle third of frons glossed with a silvery sheen 

 .... 29. riparia Fin. 

 J. Frontal orbits and occiput dull browuisli-grey. luterfrontalia 



