1900.] FAUNA OP THE WHITE NILE . 971 



9. Mutela rubens Lamarck. 



Some small Mussels also found to the south of Abu Zeit are 

 probably young specimens of this species. 



10. Mutela sp. inc. 



A very large Mussel, with beautiful iridescent pink inside, which 

 we found at Fashoda and other places on the White Nile, does not 

 entirely agree with any specimen in the British Museum 

 collection, but is closely allied to Mutela petersi, Martens. 



Family JEtheriidjE. 



11. JStheeia sp. inc. 



This shell, commonly spoken of as the " White Nile Oyster " 

 (but not really an oyster), is probably JSiheria lamarclcii. It is 

 excessively numerous, forming large beds along the river, especially 

 about El Duem, Kowa, and Abu Zeit. These being left dry by 

 the unusually low Nile were frequented by hundreds of birds. 



VIII. INSECTS. 

 Hexapoda. 



Owing to the loss of my killing-bottles &c. early in the ex- 

 pedition, only a very small collection of insects was brought back ; 

 Sir George Hampson, Bt., has kindly identified the following 

 Moths. 



Family Pyralii^e. 



G-lyphodes sericea Drury. Caught on Bahr-el-Ghazal in 

 March. 



Family NocTUiDiE. 



Sphingomorpha chlorea monteironis Euth. Also caught on 

 the Bahr-el-Ghazal in March. 



Of Beetles, the most remarkable owing to its numbers was a 

 small species of Adoretus (family Rutelidae), which on the Bahr-el- 

 Ghazel, on the nights of the 1st and 2nd April, swarmed on board 

 the steamer in incalculable thousands and was a great nuisance, 

 crawling up our sleeves, down our necks, and into our food and beds. 

 A remarkable "long-nosed bug " (Pyrops sp. inc.) was caught near 

 Heliat Nuer on the 9th April, and a large Belostoma at Fashoda. 

 Beautiful little Fireflies were a noticeable feature on many 

 evenings on the Zeraf, Jebel, and Grhazal rivers, darting hither 

 and thither over and through the reeds. 



But it was certain flies that most attracted our attention. 



Family Tabanidje. 



Tabanus dorsivitta Walker. The Seroot Fly. 



Colour. Eyes rich dark brown. Back of thorax olive-brown, 

 with four dark longitudinal lines. Abdomen : upper surface, centre 



