200 Records of the Indian Museum. [\'ol. IV, 



Tabanus geniculatus, $ , \'an der Wulp. 



Sumatra Exped. Diptera, i6, 2, pi. i, figs. 7, ya (1881). 



From Lebong (Sumatra) in May. 



Thorax dark ashy grey, substriated; abdomen brownish red, 

 the fore borders of segments brown ; antennae and palpi brown • 

 legs black, knees reddish yellow. Length 21 mm. 



Related to the former species {Tabanus inimanis, Wied.) but 

 somewhat larger and distinguished by the black legs, of which 

 alone the knees are red-yellow, by the darker borders of the 

 abdominal segments and by the darker beard. Frontal band 

 very narrow, posteriori}^ not wider, in the middle with a shining 

 black stripe-shaped line. E^'es naked, with very fine network, 

 forehead, face and cheeks with reddish grey tomentum ; face with 

 red coloured pubescence ; beard black-brown. Antennae, proboscis 

 and palpi black-brown ; the antennae on the inner side with grey 

 tomentum, the first joint triangular, the second very short, above 

 with a bristle ; the third with an acute tooth and in consequence 

 deeply indented. Thorax and scutellum with dark ashy gre}- 

 tomentum ; the thorax with indistinct stripes, between which in 

 some lights appear pale brown-3'ellow stripes ; breast sides dark 

 grey-brown ; the fore breast and fore coxae with darker pubescence. 

 Abdomen brown-red, a little metallic, with dark brown fore borders 

 to the segments ; under side black-brown with reddish segmentations. 

 Legs black with red-3'ellow knees. Wings of a grey-brown tinge, 

 along the border distinctly yellow-brown, stigma as a brown 

 shadow at the end of the subcostal vein. V. d. Wulp, Sumatra 

 Exped. Dipt., t6, 2, pi. i, fig. 7. 



Group X. 



Forehead with one square, narrow or oblong callus, alwa^'s 

 prolonged towards the vertex as a more or less narrow line, five to 

 ten times as long as it is broad. Species with the abdomen uni- 

 colorous or nearly so, sometimes darker at apex, but with no spots 

 or bands, large, m.edium-sized or small species. 



The following species are not included in the table, being un- 

 known to me, but probably belong to this group. 



Tahanus ardens, Wied. ; Macquart described the male, the ty^pe 

 of which is probably lost. 



Tabanus laotianus, 9 , and melanognathus , cf , Bigot, the 

 latter described as having a yellow abdomen and black legs, the 

 former with legs greyish black, the tibiae greyish at base. 



Tabanus ixion, cf , Osten Sacken, from Philippines. 



Tabanus fumipennis, Van der Wulp, must be nearly related to 

 Tabanus caerulescens , Macq. 



Tabanus birmanicus, Bigot. 

 Mem. vSoc. Zool. France, v, p. 653 (1892). [Aty lotus.} 



