151 
Freshwater- Shells from Central Africa. 
Hyalinia Hanningtoni. 
Testa H. Eminiance subsimilis, sed longe minor, magis aperte per- 
forata, undique minutissime spiraliter striata ; anfract. 4|, ad 
suturam marginati, conyexiusculi, incrementi lineis tenuibus, 
aliisque spiralibus microscopicis undique sculpti, ultimus in medio 
rotundatus ; apertura lunata ; perist. ad marginem columellarem 
leviter incrassatum, superne vix reflexum, sed leviter sinuatum. 
Diam. maj. 6| millim., min. 6; alt. 4. 
Hab. Same as II. Eminiana . 
Although much resembling H . Eminiana , and at first sight 
liable to be taken for the young of that species, the present 
form 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 H. Hanningtoni similis, sed magis eompressa, columella 
superne breviter expansa et reflexa, apertura latior ; superficies 
undique distinctius spiraliter striata ; umbilicus angustior. 
Diam. maj. 6| millim., min. 6 ; alt. 4. 
Hab. 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. 
Trochonanina mamboiensis. (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, mediocriter lente crescentes, supremi 2| convexi, 
minutissime et confer tim spiraliter striati, cseteri planiusculi vel 
vix convexiusculi, infra ad suturam carinati, incrementi lineis 
obliquis striati, ultimus in medio acute carinatus, inferne leviter 
convexus, striisque tenuissimis, concentricis, sculptus, haud 
descendens ; apertura parva, triangularis, longit. totius ^ haud 
sequans ; peristoma tenuissimum, margine columellari ad inser- 
tionem breviter reflexo, pallide vinoso, umbilicum semiobtegente. 
Diam. maj. 11 millim., min. 10 ; longit. 10. 
Hab. Mamboia, 4000 to 5000 feet {Last). 
This is a very fragile shell and well distinguished by its 
