1911.] 109 



lescens ; its small anteuuoB, and nearly clear wings, with but a slight 

 dark central patch, being obvious characters sufl&cient to distin- 

 guish it at a glance from helvetica. Herr Becker remarks that it is 

 close to Ch. dombressonensis ; that species, however, is described by 

 Rougemont, who published the description, as having small antennae, 

 clear wings, and no black hairs on abdomen, with a piibescence chiefly 

 grey (" flavogriseis " on thorax, and " griseis " on abdomen), and Herr 

 Becker adds that it also differs in the profile. 



One male specimen ; Aigle — Rhone Valley — Switzerland ; May 

 13th, 1910 (C. J. Wainwright). 



Chilosia rodgeksii, n. sp. 



? . Eyes hairy ; face devoid of hairs on the disc ; no bristles on margin 

 of scutellum ; frons not sulcata, hut longitudinally striate ; Zrd joint of an- 

 tenncB of medium size, dark re /-brown, not angulated, but nearly circular, 

 with a rather short thickish nearly bare arista ; pubescence throughout pale, 

 and short, especially on abdomen; legs with femora narrowly i^ale at tips ; 

 tihice pale at both ends, but only narrowly so at tips ; tarsi all dark above, 

 but paler beneath, especially on hind pair, and paler betioeen the joints ; 

 wings rusty yellow ; olivaceous species finely punctate and shining. 



9 . Head viewed in profile, with lower part of face not prodviced ; face 

 nearly perpendicular ; slightly hollowed below antennae ; central knob small ; 

 month edge not prominent; and iipper mouth edge not much above lower 

 mouth edge ; under-side of head straight and jowls abovit \ eye width ; frons 

 wide, of eye width at vertex seen from above, and widening with the face 

 evenly to under-side of head. Sculpturation of frons peculiar, scarcely to be 

 described as silicate, but the usual central sulcus indicated and bordered 

 closely by longitiidinal striae which curve outwards above for the ocellary 

 triangle and inconspicuously also below for the antennal base ; coarsely punc- 

 tate abovit the striae, but becoming more finely and sparsely punctate towards 

 the eye margins which are smooth and shining. Eyes conspicuously hairy ; 

 pubescence pale ; frons also clothed with pubescence of same length and coloiu* 

 as the eyes, becoming rather longer at the vertex ; face not very pollinose, 

 almost all shining, Avith a little tomentum under the antennae and in the 

 hollows ; eye margins i-ather wide btit regular in width, black with pale hairs ; 

 palpi yellow. Antennae medium in size, nearly circular, not angulated at all ; 

 dark with distinct f ulvovis color ; perhaps better described as reddish-brown ; 

 arista shortish, thick, same colour as antennae, with very short pubescence. 

 Thorax and scutellum olive-green, finely but closely punctate, shining, with 

 short thick pale pubescence intermixed with slightly longer hairs ; no bristles 

 on margin of scutellum. Abdomen a blacker olive-green, very finely and 

 sparsely punctate, shining ; with short, not dense, pale pubescence ; imder-side 

 dull with hoary tomentum. Wings uniformly coloured with i-ather thick veins, 

 of a rusty yellow colour ; the marginal cross vein meets the cubital (3rd longi- 



