Freshwater- Shells from Central Africa. 163 



Ennca curvilamella. (PI. VI. fig. 8.) 



Testa tenuis, subpcllucida, pupiformis, superne conoidea, baud ri- 

 mata, albida ; anfractua 8, convexiusculi, costulia teniiibus 

 obliquis instruct!, in interstitiis microscopice spiraliter intcrrupto 

 striati ; apex obtuse coiioidalis, hcvis ; anfr. ultimus antice leviter 

 ascendciis, pone labrum profunde cftbssus ; apertura parva, longit. 

 totius ^ adiequans, dcntibus duobus munita ; perist. album, 

 paulo dilatatum et reHoxum ; cc^umolla iutus lata. 



Longit. 8i uiillim., diam. 4 ; apertura 24 longa, 2 lata. 



Hah. I!iIaniboia, at an altitude of 4000 to 5000 feet [Last). 



Of tlie two teeth in the mouth of this sjoecies one corresponds 

 to the indentation behind the outer lip, the other, which is 

 lanielliform, prominent, and curved, is on the body-wall and 

 almost joined to the extremity of the labrum. The ends of 

 the fine riblets give a pretty denticulate appearance to the 

 suture. The microscopic stride do not extend from riblet to 

 riblet, but appear to be only on the left side of the riblets 

 when the shell is examined with the spire upwards. 



Ennea consociata. (PL VI. fig. 9.) 



Testa pupiformis, superne obtuse conoidea, albida, iwrum nitida ; 

 anfract. 8, convexiusculi, sutura profunda sejuncti, oblique for- 

 titer striati, ultimus antice paulo ascendcus, pone et infra aper- 

 turam scrobiculatus ; apertura sub(]uadrata, ringens, dentibus 4 -5 

 albis, ina^qualibus, in^^tructa, longit. totius -^ paulo superans ; 

 perist. album, 8ul)late dilatatum et reflcxum. 



Longit. 7 millim., diam. 3^ ; apertura 2jJ longa, 2^ lata. 



Hah. Kidete [Emin). 



This is a more slender shell than E. consanguinea, diffe- 

 rently striated, and it has different teeth in the aperture. Of 

 these one on the outer lip is almost double, a second strong 

 tooth is situated on the columella, a third smaller one witliin 

 the lower margin, a fourth much curved, hollowed out, lamel- 

 lar one adjoining the outer lip above, and, finally, a sixth 

 minute denticle occurs above the large central tooth on the 

 labrum. 



Ennea cequidentata. (PI. VI. fig. 10.) 



Testa parva, cylindracea, superne paulo latior, ad apieem obtusa, 

 albo-pellucida, nitida; an tract. 6, convexiusculi, laevigati, superne 

 ad suturam subprofundam minute denticulati, ultimus penultimo 

 angustior, prope aperturam longitudiualiter striatus, utrinque et 

 infra scrobiculatus ; apertura subi^uadrata, quadrideutata, alba, 



