Freshwater- Shells from Central Africa. 159 
millata; anfract. 11, convexi, incrementi lineis obliquis tenuibus 
striati ; apertura parva, acute ovalis, longit. totius 1 sequans ; 
columella arcuata, antice truncata. 
Longit. 15 millim., diam. 3|; apertura 3 longa, 1| lata. 
Hah. Mamboia, at an altitude of 4000 to 5000 feet {Last ) . 
The two specimens of this species at hand are probably not 
full-grown, as a faint angulation at the periphery of the body- 
whorl suggests this opinion. In that case the number of 
whorls and the proportion of the aperture to the total length 
may hereafter require modification. S. involuta , Gould, is 
similarly coloured, but is a larger and thicker shell, 
Stenogyra ( Subulina ) Emini. (PL V. fig. 19.) 
Testa elongata, gracilis, pyramidalis, subpellucida, pallide virescens 
vel flavo-viridis, polita ; anfract. 9, convexiusculi, lente crescentes, 
lineis incrementi obliquis levissime striati, sutura subprofunda, 
obliqua, discreti ; apex obtuse rotundatus ; apertura parya, ovalis, 
superne acuta, longit. totius ± paulo superans ; columella bene 
arcuata, antice oblique truncata, callo tenui albo induta. 
Longit. 16 millim., diam. 3| ; apertura 3£ longa, 2 lata. 
Hah. Mamboia, at an altitude of 4000 to 5000 feet {Last). 
This species bears a general resemblance to S. stricta , Poey, 
from Cuba, but differs in having much rounder whorls, a more 
arcuate columella, with a distinct basal truncation. S. Lasti 
is differently coloured and has shorter and more numerous 
whorls. S. mammillata , Craven, is a larger species with a 
strongly puckered suture. 
Stenogyra {Subulina) intermedia, Taylor. 
Testa gracilis, superne parum angustata, subpellucida, stramineo- 
alba, nitens ; anfract. 8-9, convexiusculi, elongati, oblique tenu- 
issime striati, superne infra suturam obliquam minute corrugata ; 
apex rotundatus, obtusus ; apertura parva, ovata, superne acu- 
minata, longit. totius -1 subaequans; columella valde curvata, 
antice abrupte truncata. 
Longit. 10 millim., diam. 2 | ; apertura 2 longa, 1 lata. 
Hah. Mamboia {Last) ; Zanzibar {Gibbons). 
This is a pale straw-coloured glassy shell with rather long 
whorls, which are minutely (not very distinctly) puckered 
above at the suture. This feature is not mentioned by Mr. 
Taylor in the original description (Quart. Journ. Conch, 
voh i. p. 282), nor is it depicted in the figure (pi. i. fig. 5), in 
which the aperture is drawn rather too narrow. 
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