2. BOMBYLIUS 501 



especially towards the sides, and these black Iiairs, though stronger and more 

 rigid than the thin yellow hairs and longer than those on the fourth and fifth 

 segments, are not very easily detected. Belly greyish black with no black 

 hairs intermixed in the pale pubescence, l)Ut when seen from beneath the 

 long black hairs on the sides and dorsal part of the alidomen become much 

 more distinct. 



Legs dull brownish orange, but the coxae, trochanters, and most of the 

 femora black, leaving the apical sixth of the anterior femora and the apical 

 quarter of the hind femora orange ; extreme tip of the hind femora with a 

 blackish spot in front ; tarsi black, but brownish at the base ; coxae and base 

 of femora with long pale yellow or brownish yellow pubescence, which 

 extends further along the anterior femora than along the hind pair ; all the 

 femora rather thickly though hardly crowdedly covered with dirty whitish 

 scales ; hind femora with a row of about seven long stiff black antero-ventral 

 bristles not extended to the basal third or more ; the small bristles on the 

 tibiae in rows of six or seven, and those on the tarsi aj^parently rather more 

 distinct on the last four joints of the front pair. Pulvilli very small and 

 ovate, dirty yellowish white. 



Wings brownish or almost brownish orange across all the base to about 

 the end of the anal cell and to about half-way across the subapical cell and 

 onwards to the costa further on, but without any definite boundary, so that 

 the hindmargin and the tip of the wing are broadly (more than one-third of 

 the wing) rather Ijrownish hyaline, or the wings may have no approximation 

 to any defined boundary between the brownish orange base and the lighter tip 

 and hindmargin ; middle cross-vein just before the middle of the discal cell ; 

 thickened black base of the costa with numerous adpressed short golden 

 hairs in front, al;)Ove, and especially behind, the hairs on the back part being 

 longer and less adpressed close to the base ; alulae with a minute dark brown 

 fringe, and with a long brownish yellow fringe on the inner edge. Alar 

 squamae not small, orange brown with a thick blackish Ijrown margin and 

 with long orange fringes. Halteres orange on the stem, and yellow or orange 

 on the top of the knob. 



? . Extremely like the male. Frons at the vertex about one-quarter the width 

 of the head but steadily widening down to below the antennas where the 

 face is about two-fifths the width of the head, dull black, with abundant 

 scaly dull yellow pubescence of which the lower corners against the eyes and 

 level with the antennae form patches of more glistening scales which contrast 

 with the adjacent long black pubescence of the side-cheeks, but on the upj^er 

 half of the sides of the frons numerous long more erect black forwards- 

 sloping hairs are interndxed, and lower down the frons (after an interval) are 

 some shorter (though still long) erect black hairs ; ocellar space as in the male 

 with a tuft of long black hairs on all the fore part (which radiate forwards) and 

 with numerous equally long dull yellow erect hairs on the back part. Eyes 

 when seen in profile more rounded in front. Antennae with the second joint 

 almost bare, and the third joint with no yellow scales on its upper side. 



Thorax, scutellum, and abdomen with more abundant very short depressed 

 pale yellow scaly pubescence (hidden beneath the long pubescence) which is 

 easily rubbed off and then leaves the abdomen dull velvety black. Anus pale 

 orange with only very short yellow pubescence. 



Legs with the small black bristles about the tip of the hind femora more 

 obvious than in the male. 



Wings more hyaline, being only a little brownish about the basal quarter 

 and along the costa to the end of the subcostal cell. 



Length about 8 inm., but varying from 7 mm. to 10 mm. 



This species resembles B. minor only of the known British species, but 

 has many close allies on the continent. It may be easily distinguished 

 from B. minor and its allies by the postocular fringe of long black hairs. 

 The closely allied B. venosus has hardly any black pubescence across the 

 face just under the antennae, and has the front part of the frons in the 

 female almost entirely pale haired, and is a rather larger species which 



