2. TABANUS 415 



pubescence ; hindmargins of tlie first six segments conspicuously and equally 

 pale yellowish ; in a variety the belly is blackish with whitish hindmargins 

 to the second to sixth segments. Genitalia hardly conspicuous, but a pair 

 of large brown side plates can be seen. 



Legs duU black with a grey tinge caused by abundant dust, but the bare 

 underside of the front femora consiiicuously black and shining as usual ; 

 in the darkest forms the knees and posterior ankles are orange, and upon close 

 examination more than the basal half of the front tibire and all the middle 

 tibicB except the tip show traces of oi'ange colour, the front tarsi being blacker 

 and slightly broader than the posterior tarsi ; but in the lighter forms the 

 front tibire are orange on the basal half (never whitish yellow as stated by 

 Brauer), as well as the middle tibiae except at the tip and the basal joint of 

 the middle tarsi for more than half its length, while the hind tibise and the 

 base of the hind tarsi are obscurely orange ; between these forms any inter- 

 mediates may occur, and I have seen a dark form in which the front tibiai 

 and tarsi were only brown (immature ? ), but it may be noted that the hind 

 tibiae are almost always all blackish ; fi'ont tibiae a little clavate, but the 

 " touch-hairs '' about the tip and on the front tarsi very inconspicuous. 

 Pubescence on the front coxaj dense white and long, behind the front femora 

 whitish except for a few black hairs near the tip, behind the middle femora 

 less abundant and whitish except for a very few black hairs close to the tip, 

 and beneath the liind femora whitish ; pubescence on the posterior tibiae 

 mainly whitish but black and almost bristly above the middle tibice, and the 

 anterior tibife with some longer black hairs towards the back part (though 

 scarcely as a fringe), while the hind tibiae have a distinct rather long and 

 coarse continuous antero-dorsal fringe and a short pale postero-ventral one, 

 the antero-dorsal fringe being usually mixed with numerous black hairs ; 

 in one specimen the fringe is entirely black and the black hairs on the middle 

 tibia? and behind the front femora are more numerous. Pulvilli brownish 

 yellow ; claws dull black, but rather brownish about the base. 



Wings almost hyaline or slightly smoky brownish ; veins dark brown but 

 becoming blackish on the outer part of the wing. Squamae glassy smoky 

 yellowish, with a conspicuous dark margin to the alar pair but a paler brown 

 margin to the thoracal pair ; fringe very short and pale, but the usual tuft 

 near the angle long conspicuous and greyish Avhite. Halteres dark brown, 

 with the top of the knob sometimes light brown. 



?. Resembling the male but greyer and less pubescent. Head much shorter 

 than in the male but quite as wide, and (when seen from above) with a more 

 regular arch behind. Face white, and there are rather long and dense white 

 hairs all over the face, cheeks, jowls, and underside of head, though the hairs 

 are longest all about the mouth ; frontal stripe brownish ashy grey, suddenly 

 but slightly contracted at its lower end and slightly widened above, very 

 broad as it is less than three times as long as its broadest part ; lower callus 

 shining black, transverse oblong, resting on the frontal triangle, and only 

 separated from the eyes by narrow grey lines ; middle callus broad (not in 

 the least linear) usually heart-shaped (being notched above) and very rarely 

 connected below by a short point with the lower callus ; ocellar callus only 

 indicated by a large blackish ashy grey space ; frontal triangle dull clear 

 yellowish with a brown cross-band as in the male extending across from eye 

 to eye both above and below the antennae and continuing somewhat down the 

 side-cheeks against the eyes ; postocular margin with a narrow greyish white 

 bare rim, behind which on the middle part of the eye is a single sparse cilia tion 

 of bristly black hairs and behind that a more abundant greyish white ciliation 

 which gTadually grows a little longer right up to the upper eye-angle ^ behind 

 the vertex are some slightly longer black hairs which have their tips bent 

 forward, and some longer grey hairs are intermixed on and about the 

 vertex • pubescence on the rest of the frontal stripe almost down to the 

 lower callus shorter black and sloping forward, or sometimes pale on the 

 sides and lower part. Palpi yellowish white (or rarely orange yellow) with 

 whitish silky pubescence beneath the base of the second joint and usually 

 with short black bristles mixed with tiny inconspicuous whitish ones on the 

 upper and outer sides, but a Scotch specimen identified by Brauer has not 



