SOME HLOOD-SUCKING AND OTHEE DIPTERA FEOM THE ANGLO-EGYPTIAN SUDAN 



59 



Head: face and jowls whitish poUinose and cdothed with white hair; lower callosity ou 

 front pale ochraceous, squarish, and occupying whole width of front immediately above 

 angles of eyes ; upper callosity situated in middle of front, reddish brown and ovate ; first 

 joint of antennae cream buff, with upper angle strongly produced, and capped with a tuft of 

 minute black hairs, forming a black tip; second joint very small ; thinl joint rather broad 

 at base, with conspicuous basal augle ; extreme tip of third joint dark brown ; })alpi 

 somewhat swollen towards base, cream-buflP, clothed with whitisli hair interspersed with a 

 few black hairs ou outside. 



Thorax : dorsum with a grey stripe on each side, anil a narrow median and a pair of 

 broader admedian stripes ; the three latter 

 are rather brighter in tint. 



AMoiiwn : median stripe starting from 

 a somewhat semicircular spot on hind margin 

 of first and increasing in width from base 

 of second to fourth segment, where it is 

 broadest, then narrowing rapidly and ter- 

 minating ou hind margin of sixth segment ; 

 lateral stripes with a somewhat zigzag out- 

 line on outer side ; lateral margin and under 

 side of abdomen pearl grey. fjg. 23.— Tadanus ceatus, Lw. ? 



r i" i. ■ 1 • 1* r -1 ■ South Africa to Nigeria 



J^ei/S : iront tarsi and tips 01 irollt ilhuS Head and legs yellowish, front tarsi entirely, middle and hind tarsi, 



-.-.^ liP ' ' ± p -111 1 except base, brown ; thorax grey, abdomen brown, the former witii 



nark brown; last tour joints Ot middle and light grey, the latter with whitish stripes. 



hind tarsi, tips of middle and hind tibiae and of first joints of middle and hind tarsi brown. 



Hahcres : knob pale yellow, stalk buff'. 



Tabaniis tjnctus is evidently a widely distributed species, for, while the typical specimen 

 is stated by Loew to have been collected in " Caftraria," the Museum series includes examples 

 from Fajao, Victoria Nile, Uganda, November 1904. {Captain E. D W. Giriij, 1 M S.), 

 and also from the vicinity of Yola, Northern Nigeria, April 14, 1905 ( W. F. Goivers). 



I'aliauiis socius, Walk. 



(Fig. 24) 

 IIi/hiiiks xocitis, Walker, List Dipt. Ins. in coll. Brit. Mus., I. (1848), p. 16U. 



This species can be distinguished from TalHiimx rii-ija/iis, Austen {ilomivitta, Walk.) 

 (Fig. 26), which it closely resembles in general appearance, by the edges of the median 

 grey longitudinal stripe on the abdomen being notched or serrate instead of smooth. To 

 judge from the relative numbers of specimens in the British Museum collection, Tahanus 

 socius would appear to be the commonest Seroot-fly on the White Nile. In addition to a 

 very long series of examples taken at Kodok on December 6th, 1900, by the late 

 Captain H. E. Haymes, the Museum possesses others collected and presented by 

 Major H. N. Dunn, Captain 8. S. Flower (" about ten miles south of Jebel Ain, White Nile, 

 March 17, 1900 "), and Major E. H. Penton, D.S.O. (Bahr-El-Ghazal, February, 1905). 

 The species was found by Colonel G. D. Hunter, D.S.O. in May, 1905, on a boat in the sudd 

 south of Nal Nusr, between Gondokoro and Tautikia, and Major Pentou also met with it in 

 Senaar, in 1899. 



The type of T. socius is from " South Africa " ; other specimens of the species in the' 

 Museum collection are from the Transvaal and the Congo Free State. 



Tabanus 

 socius 



