On new Shells froiu Lake Tantjani/ika. 0-5 



lu'iitiU-s and Ralraeliians were sent to the Hiitish Musnini hy 

 Dr. Kniin Paslia : — 



South Shore of Victoria Nyanza. — Nucras tessellat'i, Smith ; 

 Eremias Spekiij Gtlir. ; Lygos^oma inodrsfnm, Crtlir. (a single 

 spceinien, with 24 scales round the body and the nasal eoni- 

 ])letely divided into two) ; Dromojiltis ain/ofensis^ 13iteag-3 ; 

 l\amino^)hifi hiseriatus^ Ptrs. ; Thelotornis Kirtlaadii, Hallo .v. 



Ugogo. — Meyalixalus Fornasiniiy liianeoni. 



VII. — On a new Genns and some new Sjiccies of Shells from 

 Lake Tanganyika. By EdgAR A. Smith. 



Mr. E. Coode Hore recently presented to the British Mu- 

 seum a few TanganjMkan shells preserved in spirit and con- 

 taining the animals. Among them are two specimens of 

 Paramelania nassa^ var. grandis *. 



This variety I now propose as the type of a new genus, 

 wliich may be designated Nassopsis, distinguished from Para- 

 melania t (henceforth reserved for P. Damoni and P. crassi- 

 gronulata) ])artly on account of certain differences in the 

 shell, but more especially as tlie operculum is of an entirely 

 different type. 



In Paramelania the aperture of the shell does not exhibit 

 the sinuation or subtiuneation of tlie columella which is so 

 conspicuous in typical jSassopsis, and the antei'ior extremity 

 of the last whorl has a slightly produced appearance ; the outer 

 lip also is more thickei;ed. The operculum in Paramelania 

 is large, ovate, paucispiral at the nucleus, situated a little 

 within the left margin and about equidistant from the ends, 

 and subsequently displays a concentric style of growth. That 

 of Nassojjsis is small and somewhat paucispiral at the almost 

 terminal nucleus. 



Nassopsis nassa, var. grandis. 



Animal with the foot small, broader in front than behind, 

 with the anterior margin double; sides of the foot and head 

 blackish ; proboscis compressed, broad and truncate at the 

 end ; tentacles also black, except at the tips, which are pale, 

 very short, conical, swollen at the base on the outer side, 

 probably denoting the position of the eyes ; free edge of the 

 mantle dark-coloured and subdenticulate. 



* Proc. Zool. Soc. 1881, p. 501, pi. xxxiv. %. 20 «. 

 t L. c. p. 559 { = Bonrytdynatiu, Ginuid). 



