7. SARGUS 181 



witli the genitalia. Belly with short inconspicuous rather scarce pale 

 brownish-yellow pubescence on the three basal segnients,_ but black and 

 denser elsewhere though very inconspicuous because so minute. Genitalia 

 black and large, the lateral plates being very large and nearly quadrate and 

 covering all the sides, but with small lamellae projecting from the end upper 

 corners. 



Legs black ; knees rather conspicuously brownish orange and that colour 

 extending clown about an eighth of the anterior, and a third (though 

 obscurely) of the hind, tibiae ; the usual dilatation of the apical half of the 

 anterior' tibiae and the kink on the hind tibiae very _ slight. Pubescence 

 behind the anterior femora pale but slight, and very slight in front of the 

 hind femora. 



Wings smoky, but without any sig-n of a cloud, though the stigma and the 

 costal space near are inconspicuously brownish. Squamae blackish with pale 

 bro-R-nish fringes, the thoracal pair being narrow club-shaped. Halteres pale 

 orange. 



9 . Unknown or unrecognised. 

 Length about 7 mm. 



This species is easily distinguished from >S^. iridatus and S. cupraruis 

 by the absence of any outstanding long whitish postociilar ciliation, as well 

 from >S^. nuhcculosus which also has that ciliation but has it black in the 

 male ; the black legs distinguish it from S. hipundatiis, S. alhiharhis, and 

 S. minimus, while the absence of any trace of golden pubescence on the 

 disc of the abdomen distinguishes it from S. rvfipcs and to a certain extent 

 from S. flavipes. S. alhiharhus, fiavipes, rufipes, minimus, and nitidus have 

 a common type of frons, which is broader than in the other species, and 

 has a broad bare shining middle part extending from the front ocellus to 

 near the white frontal spots, and as all these species also do not have the 

 outstanding postocular pubescence of S. cujjrarius, etc., they form a natural 

 group. If S. nit idles (as interpreted by me) is not a good species it must 

 fall under S. flavipes, and a specimen taken by Mr C. G. Lamb at "Whittles- 

 ford in Cambridgeshire in July 1903 exhibits a tendency that way, as it has 

 the sides of the abdomen with pale pubescence to the end of the fourth 

 segment extending rather obscurely on to the disc about the hind 

 corners of the segments and even a little on to the disc of the basal 

 segments but not showing any reddish-orange colour, while the stubby 

 black pubescence on the disc is not so apparent but is very dense on the 

 disc of the fourth and fifth segments ; this specimen also has the basal 

 third of the anterior tibias orange and the tip faintly so, nearly the basal 

 half of the hind tibise and the base of the hind and middle tarsi brownish 

 orange, and the brownish stigma and space near more blackish. 



>S'. nitidus is a very little known species, or may represent only 

 small dark specimens of other species. My main description has been 

 made from a very distinct-looking specimen which was taken by Dr J. H. 

 Wood at Tram Inn in Herefordshire on July 15, 1903, while I have referred 

 to a rather similar male which was taken about the same time by Mr C. 

 G. Lamb at Whittlesford in Cambridgeshire. I have also seen a very well- 

 marked male which was taken by Eev. W. J. AVingate at Hesleden in 

 Durham on August 13, 1900, but a small male taken at Boat o' Garten in 

 Inverness is in my opinion a specimen of S. rufipes. 



Si/mnijmj/. — It is just possible that .S". nitidus is only a small dark variation of S. 

 ^ai'ipes, but it seems to have occurred in localities where S._J^avipes is unknown. It 

 is also possible that the original S. nitidus of Meigen is quite distinct and founded 



