Freshwater- Shells from Central Africa. 167 



the suture, but are most distinct around the umbilical depres- 

 sion. 



Ennea pecuUaris, (PI. VI. fig. 18.) 



Testa parva, pupiformis, vix rimata, albida vel pallide straminea, 

 nitida, striis coufertis, oblique curvatis, conspicuis sculpta ; anfract. 

 7, apicales duo Itevigati, superne obtusi, ca3teri convexi, sutura 

 leviter obliqua, profundiuscula jiuicti, idtimus antice contractus, 

 pone labium baud profuude scrobiculatus ; apertura parva, 

 longit. totius \ ada^quans, superne peculiariter sinuata, dentibua 

 tribus munita ; perist. leviter incrassatum, subreflexum, margini- 

 bus callo tenui junctis, dextro superne circulariter sinuato. 



Longit. 4 millim., diam. 2 ; apertura 1 longa et lata. 



Hah. Mamboia, at an elevation of 4000 to 5000 feet [Last) . 



The peculiar, almost circular sinus at the upper part of the 

 aperture is formed by the outer lip bending forward in the 

 middle into a tooth-like projection, vi^hich is almost met by a 

 prominent but not very thick tooth on the whorl and adjoining 

 the termination of the labrum. The third denticle is small 

 and situated within the lower margin of the aperture. The 

 columella at the upper part seems to exhibit far within a 

 broad horizontal plate, but being so far within the aperture, it 

 is not easily defined. 



EXPLANATION OF THE PLATES. 

 Plate V. 



Figs, 1, 1 a. Hyalinia Lasti. 

 Fig. 2, Hyalinia Eminiana, 

 Fig, 3. Trochonanina tnamboiensis. 

 Fig, 4. Trochonanina episcopalis. 

 Fig. 5, Bidimus {Rhachis) usagaricus. 

 Fig, 6. Bulimus {Rhachis) quadricingulatus. 

 Fig, 7. Bulimus (^Cerastus) mamhoiensis. 

 Fig. 8. Bulimus {Cerastus) Emini. 

 Fig. 9. Bulimus (Cerastzis) kidetensis. 

 Fig, 10. Bulimus ( Cerastus ?) unipUcatus. 

 Fig. 11. Bulimus (^Cerastus?) introversus. 

 Fig. 12. Bulimus (^Hapalus) suhvirescens. 

 Fig, 13. Bulimus (Hapahis) dispanlis. 

 Fig, 14. Bulimus (^Hapalus) associatus. 

 Fig. 15. Stenogrjra {Subulina) subcarinifera. 

 Fig. 16. Stenogyra {Subulina) mamboiensis. 

 Fig. 17. Stenogyra {Subulina) usagarica. 

 Fig. 18. Stenogyra (Subulina) Lasti. 

 Fig. 19. Stenogyra {Subulina) Emini. 

 Fig. 20. Stenogyra (Opeas) stenostoma. 



