Freshwater- Shells from Central Africa. 15 1 



llya li n ia Ha n n ington i. 



Testa II. Eminiano' subsimilis, scd longe minor, magis apertc per- 

 forata, undique minutissirnc spiralitcr striata ; anfract. 4^, ad 

 suturam niargiiiati, convexiusculi, iiicreraenti lineis tenuibua, 

 aliisquc spiralibiis microseopicis undique sculpti, ultimiis in medio 

 rotundatus ; apcrtura luiiata : perist. ad marginem columcUarom 

 levitor inerassatum, sujierne vix retloxum, eed leviter siuuatum. 



Diam. maj. (>.\ millim., min. G; alt. 4. 



J/ah. Same as //. Eminiana. 



Althougli much resembling //. Eminiana, and at first sight 

 liable to be taken for the young of that species, the present 

 foiin is quite distinct. The umbilicus is larger, the columella 

 is peculiarly sinuated or notched near its junction with the 

 body-whorl, and scarcely at all reflexed, and the surface is 

 everywhere above and below microscopically spirally striated. 



Hyalinia depressior. 



Testa //. HanniiKjtoni similis, scd magis compressa, columella 

 supernc brcviter expansa et reflexa, apertura latior ; superficies 

 undique distinctius spiraliter striata ; umbilicus angustior. 



Diara. maj. Gg millim., min. 6 ; alt. 4. 



Hah. Mamboia, altitude 4000 to 5000 feet {Last). 



Although the measurements of this form and H. Hanning- 

 toni are similar, still the two species are quite distinct. This 

 can be seen at a glance when they are placed side by side, 

 and the distinctness is confirmed by the differences referred to 

 in the above description. 



Trochonayiina mamhoiensis. (PI. V. fig. 3.) 



Testa acute conica, ad peripheriam carinata, tenuissima, anguste 

 perforata, nitida, cornea, pallide fusco-olivacea ; spira elevata, 

 lateribus subrectis vel levissime concavis, ad apicem subobtusa ; 

 anfract. 6-7, medioeriter lente crescentes, supremi 2| convexi, 

 minutissime et confertim spiraliter striati, cseteri planiusculi vel 

 vix convexiusculi, infra ad suturam carinati, increment! lineis 

 obliquis striati, ultimus in medio acute carinatus, inferne leviter 

 convexus, striisque tenuissimis, concentricis, sculptus, baud 

 descendens ; apertura parva, triangularis, longit. totius |- baud 

 aequans ; peristoma teni;issimum, margine columellari ad inser- 

 tionem breviter reflexo, pallide vinoso, umbilicum semiobtegente. 



Diam. maj, 11 millim., min. 10 ; longit. 10. 



Ilah. Mamboia, 4000 to 5000 feet {Last). 



This is a very fragile shell and well distinguished by its 



