NOVITATES ZOOLOGICAE XXI. 19H. 267 



Note. — As a small contribntioa to onr knowledge of the Asilidae of Algeria, 

 there is here appended a description of a new Algerian species of Dasypogoninae, 

 represented by a specimen from Biskra in the British Museum (Natural History). 



Genus TRICLIS Lw. 

 Triclis nifescens sp. nov. 



<S. Length (1 specimen) 11-4 mm. ; width of head 3-25 mm. ; length of wing 

 8 mm. 



Leffs awl third joint of antennae cinnamon-coloured, tibiae at base, and on 

 upper surface nearbj to tips, and first and second joints of antennae paler (buff or 

 ochraceous-buff), hind tibiae each ivith a j^air of not sharphj defined dark brown 

 spots on upper side just before tip ; ground-colour of thorax and abdomen ochraceous- 

 j-ufous, concealed in case of thorax by a dense covering of light isabella-colourcd 

 pollen ; wings hyaline, distal extremity of marginal cell very obtuse, end of second 

 longitudinal vein turning abruptly towards costa, small transverse vein close to base 

 of discal cell. 



Head: front and occiput covered with smoke-grey pollen, front otherwise 

 appearing bare, though sparsely clothed on each side, like upper portion of sides of 

 occiput, with stifi", erect, yellowish hair ; ocellar tubercle conspicuous, bearing at 

 its apes a tuft of divergent yellowish bristles ; face thickly clothed with down- 

 wardly directed yellowish-white hair ; mystax of same colour ; basi-occipital region 

 and lower portion of sides of occiput clothed with whitish hair ; proboscis, except 

 distal third which is clove-brown, cinnamon-coloured, clothed below with yellowish 

 hair ; palpi cinnamon-coloured, clothed below with yellowish hair ; first and second 

 joints of antennae thinly clothed with yellowish hair, first joint also bearing similarly 

 coloured bristles on under surface ; third joint of antennae elongate, about one-third 

 longer than first and second joints taken together, when viewed from side its upper 

 margin appearing straight, its lower margin descending to some extent beyond 

 proximal third and rising again just before distal extremity; antennal style dark 

 brown. 



Thorax : dorsum clothed with fine, appressed, glistening hair of a lighter shade 

 than poUinose covering, and longer ijosteriorly and on scutellum than on anterior 

 two-thirds, supra-alar and post-alar bristles pale yellowish ; hind border of scutellum 

 devoid of pollen ; hair on pleurae whitish, sparse except above anterior coxae and 

 also in front of halteres, where there is a tuft of longer hair on each side. 



Abdomen- somewhat narrow and semi-cylindrical from third segment to distal 

 extremity, thinly covered with pollen which is of same tint as that on thorax, but 

 is not so dense as to conceal ground-colour, hypojiygium, however, and a narrow 

 band on anterior margin of tergites of third and three following segments devoid 

 of pollen and shining, tergite of short first segment, except each lateral extremity, 

 also shining ; dorsum clothed with short, appressed, pale, shining hair, for most 

 part of same colour as that on dorsum of thorax, but whitish and longer on sides 

 of first five segments ; on second and two following tergites, as also to some extent 

 on fifth tergite, the hair curves outwards on each side of the middle line, so that 

 this portion of abdomen has somewhat of a " crimped and curled " appearance ; the 

 latter is enhanced by the narrow, shining bands, already alluded to, on the tergites 

 of the third and three following segments, which cause each of these segments to 

 appear sharply marked ofi" from the preceding one ; hind margins of fourth and 



