364 TABANID^. 



on the basal joint (as in T. distiTiguendiis), but the second and third joints 

 much darker, the third being usually obscurely dull reddish about the base 

 though sometimes very slightly so, while the basal segment of this joint is 

 nearly twice as long as its depth at the hump. 



Thorax greyish black, sometimes with two Avidely separated indistinct 

 lighter grey stripes on the front part : prtealar calli sometimes dark ferrugin- 

 ous ; the erect black pubescence shorter, and with a few depressed thin pale 

 hairs interspersed, and the pale hairs becoming conspicuous and more erect about 

 the front part, on the back part near the scutellum, and near the wing-base ; 

 pleurae dusted ashy grey with mainly long pale yellowish grey pubescence, 

 but with blackish grey hairs intermixed but not dense on the disc of the 

 mesopleurae, though the extreme back part of the mesopleurse bears a more 

 or less conspicuous dense pale tuft. 



Abdomen brownish black, glistening, with the hind corners of the first 

 segment (extending considerably along the hindmargin) and the front corners 

 of the second segment (extending out considerably on to the disc), rather 

 obscurely brownish red ^ this brownish red colour however varies considerably 

 in extent, as it is sometimes quite inconsi^icuous while it may occasionally be 

 broad and conspicuous at the sides of the two basal and on most of the third 

 segments, or there may be only two small brownish red s^jots on the third 

 segment in addition to the brownish red sides of the two basal segments ; 

 pubescence forming rather consi:)icuous grey triangles (diminishing in size) 

 on the middle of the second to fifth hindmargins and extending almost to the 

 foremargins at their points, and the grey pubescence about the hind corners 

 of the second segment and about the sides of the third to fifth segments 

 almost forming the usual rows of grey side-flecks so frequent in the Tabankke, 

 and to confirm this there are (when seen from behind) faint indications of a 

 middle and two side rows of rather large brownish spots, while on each side 

 of the middle triangle of grey pubescence the abdomen is blackish ; hind- 

 margins of the fifth to seventh segments rather ferruginous (especially 

 towards the sides) though any pale hindmarginal fringes are very indistinct ; 

 sidemarginal pubescence mainly pale but including a few black hairs on 

 the basal part of the segments. Belly sometimes all greyish black, or at 

 other times with the upper reddish markings showing through but varying on 

 until the sides are extensively dull brownish red, while in extreme cases only 

 the large basal spot is blackish with the tip and the broad middle stripe 

 (nearly one-third of belly) greyish black, and in one case even this middle 

 stripe is absent ; second to seventh hindmargins narrowly greyish white ; 

 pubescence short depressed and pale, though a few inconspicuous black hairs 

 occur down the middle which are more noticeable on the two or three 

 terminal segments ; there is no special tuft about the middle of the base and 

 there are no obvious hindmarginal fringes. 



Legs with the front coxse ashy grey and bearing long brownish grey 

 pubescence ; femora all greyish black with a slight yellowish tinge and 

 bearing comparatively short pale fringes behind, but the bare subfemoral 

 space on the front femora contrastedly black ; middle tibiae Avith scarcely 

 any longer ciliation ; hind tibiee with a slight coarse black dorsal ciliation. 



Wings and halteres as in the male, but the disc of the squamte rather 

 paler. 



Length about 13 mm., but varying from 11 mm. to 15 mm. 



This species may be distinguished from most of its British allies 

 by the absence in both sexes of any tuft of longish black hairs on the 

 upper part of the vertex ; from T. tropicus it may also be distinguished 

 by its smaller size, paler hind tibiee, shorter pubescence on the basal joint 

 of the antennae, and much less pubescent posterior tibiae ; T. luridus is a 

 blacker species and has the frontal triangle of the female brightly shining, 

 the eyes with lunger darker pubescence in both sexes, and the eyes of the 

 male actually touching for a much shorter distance; T. distingucndus and 

 T. solstitialis are rather larger and have the abdomen both dorsally and 

 ventrally much more conspicuously orange-red in both sexes, while T. 



