On a neir Species o/'Oligoneuila. 243 



tarsi muramy-bvown, last joiut and tips of the three pre- 

 ceding joints dai'k browu. 



German East Africa : type and eight other specimens 

 (para-ty[;es) from a water-hole in the Usangu District, 

 26. xi. 19 10, and two additional specimens from the Uhehe 

 District, 3000 to 3500 ft., 2:2-27.xi.l910 {S. A. Neave : 

 presented by the Entomological Research Committee). In 

 addition to the foregoing the following material, in possession 

 of the Entomological Research Committee and also collected 

 by Mr. S. A. Neave, has been studied : one para-type from 

 the Usangu District, and ten other specimens from the 

 Uhehe District — remaining data in each case as before. 



In the shape of its frontal callus and upper frontal callus, 

 as also in that of the terminal joint of its palpi, Tabanus 

 triavyuliger shows some affinity to T. pallidifacies, Surcouf, 

 Avliich hitherto has been found only in the (British) East 

 Africa Protectorate. Apart, however, from its very different 

 fades, due to the development of the grey abdominal 

 markings into a triple series of broad triangles, as described 

 above, T. tricwgullger is distinguishable from T. pallidi- 

 facies by, among other pharacters, its front being distinctly 

 narrower, and by the inner margins of the eyes bordering 

 it being more regularly parallel, instead of somewhat 

 divergent above. From T. distinctus, Ricardo, T. trian- 

 (juliger, apart from its abdominal markings, may be dis- 

 tinguished at once by its broader front, and differently 

 sha')ed (less elongate) frontal callus. From the variatus- 

 form of T. tceniula, Pal. de Beauv., the new species, apart 

 from the greater development of its abdominal triangles, is 

 distinguishable by the shape of its frontal callus and of the 

 third joint of its antennae, as also by its pale femora. It is 

 scarcely necessary to add that in the foregoing comparisons 

 the female sex is alone considered. 



XXXI. — On a new Species o/Oligoneuria (Ephemeridse) 

 from British East Africa. By Rev. A. E. Eaton. 



Oligoneuria dobbsi, sp. n. 



Adult (drie;l) ? . — Wings transparent light blackish grey, 

 with a faint dull violet-purple gloss and intense sepia-brown 

 longitudinal neuration ; the cross-veinlets not bordered 



