— 219 — 



rather deepl}' irapressed; umbilical area widely excavated, suddenly 

 narrowing below into a uarrow, deep perforation ; peristome esserted, con- 

 tinuons, sorraewhat reflexed especiallj^ below, sinuous above; aperture irre- 

 gularly subquadrate, bearing a single, oblique, pariétal lamella. 



Alt. 2, diam. raaj. 1.75 mm. 



Aperture : ait. 0.25, diam. 0.25 mm. 



Hab. — Naivasha, British East Africa. 



Ennea naivashaensis sp. n. — PI. XI, fig. 3. 



Shell minute, cylindrical, yellowish white; whorls 7, the tirst three 

 rapidly increasing, the last elongately strangulate behind the outer lip, 

 sculptured with oblique, moderately distant riblets; suture impressed; colu- 

 mella vertically descending, outwardly expanded over the umbilical area ; 

 labrum slightlj' reflexed especiallj" below; aperture somewhat irregulaiiy 

 triangular, edentulate. 



Alt. (nearly) 2, diam. 0.75 mm. 



Hab. — Naivasha, British East Africa. 



Ennea Tomlini sp. n. — PI. XI, fig. 4. 



Shell cylindrical, yellowish brown, somewhat thin; whorls 6 '/,, the first 

 three rapidly increasing, the last ascending in front and bearing a strangulate 

 dépression inst below the peripher}' and immediately behind the peristome, 

 sculptured with fine, oblique, somewhat wav}' riblets; suture impressed; 

 umbilical dépression narrow; labrum white, dilated, somewat reflexed; 

 aperture subrectangular, bearing a single, oblique^ pariétal lamella and a 

 denticle on the outer lip. 



Alt. 4.5, diam. 1.75 mm. 



Aperture : ait. i, diam. 0.5 mm. 



Hab. — Naivasha, British East Africa. 



Thapsia conuloidea sp. n. — PI. XI, fig. i. 



Shell differing from Hélix zanguebarica Craven (') 'from Magila, East 

 Africa, in its rather higher spire and slightly more inflated base, smaller 



(') Proc. Zool. Soc, London, 1880, p. 217, PI. XXII, fig. 4. 



