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Freshwater-Shells from Central Africa . 
Bulimus ( Cerastus ) kidetensis . (Pl. V. fig. 9.) 
Testa anguste umbilieata, elongato-ovata, superne prolongata, nitida, 
subpellucido-albida, oblique regulariter eonfertim striata et tenuiter 
lirata ; apex mediocriter acutus ; anfract. 8, convexi, lente cres- 
centes, sutura profunda vix obliqua discreti ; apertura ovata, 
pyriformis, longit. totius ^ paulo superans ; perist. tenue, mar- 
gine columellari modice dilatato et reflexo. 
Longit. 15| millira., diam. ma.j. 8, min. 7 \ ; apertura 6 longa, 3| 
lata. 
Hab . Kidete ( Emin ) ; on the plains within 50 miles of 
Mamboia ( Last ). 
Although similarly sculptured this is a smaller form than 
B. Lasti, the spire is longer, and the proportions altogether 
different. A small variety, consisting of seven whorls and 
only 12 millim. long, was collected by Bishop Hannington in 
Usagara. 
Bulimus ( Cerastus ?) uniplicatus. (PI. V. fig. 10.) 
Testa anguste umbilieata, ovata, superne producta, parum nitida, 
albida, epidermide tenui flavescente induta, oblique tenuiter 
liratula ; anfractus 7, perconvexi, regulariter sublente accres- 
centes, sutura leviter obliqua, profunda, sejuncti ; apex obtusus ; 
apertura parva, ovata, longit. totius ^ paulo superans ; perist. 
tenue, margine columellari dilatato, modo leviter reflexo, intus 
plica obliqua intrante basim versus instructo. 
Longit. 14 millim., diam. maj. 7|, min. 6f ; apertura 5^ longa, 3^ 
lata. 
Hab . Mamboia, at an elevation of 4000 to 5000 feet. 
This species has a fold towards the base of the columella 
similar to that in B. ptychaxis , Smith, a much larger shell 
from Ujiji. The peristome on the columellar side is not 
much reflexed over the umbilicus, but forms a continuous 
curve with the basal margin. 
Bulimus ( Cerastus ?) introversus . (PI. V. fig. 11.) 
Testa elongata, superne acuminata, anguste rimata, haud nitida, 
tenuis, viridi-cornea ; apex introversus ; anfract. 7 , duo vel tres 
primi subfortiter costulati, cseteri convexiusculi, oblique striati, 
ultimus circa medium carina obsoleta cinctus; apertura ovata, 
longit. totius ^ paulo superans; perist. tenue, margine colu- 
mellari sublate dilatato, supra rim am aliquanto reflexo, intus, 
basim versus, oblique subtruncato vel plicato. 
Longit. 16 millim., diam. 7 ; apertura 6 longa, 4 lata. 
Hab. Mamboia, at an elevation of 4000 to 5000 feet. 
