448 MAJOR E. E. AUSTEN. 



reaching hind border) on each segment from second to sixth, inclusive ; first (visible) 

 ventral scute with a smaller, blackish, median quadrate blotch, which can be seen 

 between the hind coxae ; seventh sternite mouse-grey, with a darker median blotch, 

 smaller than that on preceding segment ; hind margins of second to sixth ventral 

 scutes, inclusive, more or less distinctly cream-buff ; entire venter with a thin pollinose 

 covering of pale smoke-grey, which, when abdomen is viewed at a very low angle 

 from behind, entirely conceals the median blotches ; median blotches on fifth and sixth 

 ventral scutes clothed with semi-erect black hair ; terminal segment, except towards 

 lateral extremities of hind margin, clothed as usual with coarse, erect black hair ; 

 venter, except as stated, clothed with short, appressed, glistening whitish or yellowish 

 hair. Wings : Tinged with mouse-grey ; veins chiefly mummy-brown, in places, such 

 as base of third and proximal portion of fifth longitudinal, paler ; stigma elongate, 

 almost colourless and scarcely distinguishable. Squamae smoke-grey or drab-grey, 

 with brownish borders clothed with pale hair. H alter es : Knobs cream-coloured, 

 stalks sepia-coloured or paler. Legs : Coxae pale smoke-grey, clothed with whitish 

 hair ; femora, except extreme tips, black or olivaceous black, with a pale, smoke-grey, 

 pollinose covering, which is, however, largely wanting on the inner side of those of 

 the front legs, and in case of middle and hind femora is denser on lower portion of 

 outer surface than elsewhere ; extreme tips of front femora cream-buff, those of middle 

 and hind pairs cinnamon-coloured, all femora clothed with whitish hair ; front 

 tibiae, except distal third, which is blackish brown, cream-buff, clothed with minute, 

 appressed, glistening cream-coloured hairs mixed with minute black hairs ; middle 

 and hind tibiae pinkish-buff (their extreme tips reddish brown), middle tibiae clothed 

 similarly to those of front pair with a mixture of minute cream-coloured hairs and 

 black hairs, and with longer black hairs on posterior margin of extensor surface ; 

 hind tibiae clothed mainly with minute, appressed, glistening cream-coloured hair, 

 and having on outer margin of extensor surface a fringe of medium length composed 

 partly of black, partly of cream-coloured hair ; front tarsi black, middle and hind 

 tarsi dark brown or blackish-brown above, proximal segment in case of middle and 

 hind tarsi somewhat paler at base ; all tarsi clothed above with minute black hairs, 

 second and following (particularly third and fourth) segments of front tarsi consider- 

 ably expanded, second and following segments of middle tarsi also somewhat expanded. 



Bangkok, November, 1919 (F.J. Godfrey). 



The species just described, which is allied to Tabanus striatus, Fabr., and to 

 T. ienens, Walk, (see above, p. 445), is distinguished from the fomier of these, in the 

 2 sex, by the shape of the frontal callus ; by the median longitudinal stripe on the 

 dorsum of the abdomen being as fully developed on the second segment as on the 

 following ones ; by the outline of the third and fourth segments of the front tarsus, 

 viewed from above being rounder ; and by the distal portion of the expanded part 

 of the third antennal segment being narrower and more elongate. From T. tenens. 

 Walk., the new species is distinguishable in the $ sex owing to the shape and darker 

 coloration of the frontal callus, and to the expanded portion of the third segment 

 of the antennae being more attenuate. 



Tabanus virgulatus is also very closely akin to T. rubidus, Wied., and to the 

 Indian T. priscus, Walk. (syn. T. albimedius, Walk.). As regards the former, it 

 would seem that, in addition to the differences given in the Key above (see p. 435), 

 T. virgulatus is distinguishable in the $ sex owing to the interval between the lower 

 portion of the frontal callus and the eye on each side being distinctly narrower. 

 It is quite possible that, when further material in good condition and from different 

 countries is available for study and comparison^ it will ultimately be found that both 

 T. virgulatus, Austen, and T. priscus, Walk., are forms of a single widely distributed 

 species, namely T. rubidus, Wied. 



10. Tabanus rubidus, Wied. 



Tabanus rubidus, Wiedemann, Diptera Exotica, i, p. 69 (1821). 



