93 
On new Shells from Lake Tanganyika . 
Beptiles and Batrachians were sent to the British Museum by 
Dr. Emin Pasha : — 
South Shore of Victoria Nyanza . — Nucras tessellata, Smith ; 
Eremias Spekii , Gthr. ; Lygosoma modestum , Gthr. (a single 
specimen, with 24 scales round the body and the nasal com- 
pletely divided into two) ; Dromophis angolensis , Bocage ; 
Psammophis biseriatus , Ptrs. ; Thelotornis Kirtland ii, Hallo v. 
TJgogo . — Megalixalus Fornasinii , Bianconi. 
VII. — On a new Genus and some new Species of Shells from 
Lake Tanganyika . By Edgar A. Smith. 
Mr. E. Coode Hore recently presented to the British Mu- 
seum a few Tanganjnkan 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, 
which may be designated Nassopsis , distinguished from Para- 
melania | (henceforth reserved for P. Damoni and P. crassi- 
granulata) partly on account of certain differences in the 
shell, but more especially as the operculum is of an entirely 
different type. 
In Paramelania the aperture of the shell does not exhibit 
the sinuation or subtruncation of the columella which is so 
conspicuous in typical Nassopsis , and the anterior extremity 
of the last whorl has a slightly produced appearance ; the outer 
lip also is more thickened. 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 Nassopsis 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. 3881, p. 561, pi. xxxiv. fig. 26 a. 
t L. c. p. 559 ( = Bourguignatia, Giraud). 
