800 MR. H. B. PRESTON ON NEW GENERA AND 
growth-strie ; suture impressed; base of shell somewhat inflated ; 
umbilicus moderately wide and deep; columella rather outwardly 
expanded, descending in a curve, oblique below; labrum thin, 
slightly reflexed ; aperture very broadly sublunate. 
Alt. 6°5, diam. maj. 11:25, diam. min. 9°25 mm. 
Aperture: alt. 5°5, diam. 5 mm. 
Hab. Nairobi, British East Africa. (A. Blayney Percival.) 
BLAYNEYELLA MICROSPIRALIS, sp. n. (PI. I. fig. 18.) 
Shell allied to B. purpureocincta Preston, but differing from 
that species in its much more depressed form, more obliquely 
descending columella, and narrower and more compressed aperture, 
and finely spirally sculptured first whorl, which sculpture is only 
visible by the aid of the microscope. 
Alt. 6, diam. maj. 10°25, diam. min. 8-5 mm. 
Aperture: alt. 4°5, diam. 4°5 mm. 
Hab. British East Africa. 
LAROGIELLA, gen. nov. 
Shell umbilieate, thin, corneous, turbinate, transversely plicate ; 
labrum membranaceous. 
Genotype: Z. venatoris Preston. 
To the above genus should also be assigned :— 
Natalina permembranacea Preston, from 8.W. Uganda, Proc. 
Zool. Soc, London, 1912, p. 183, pl. xxxi. figs. 20, 20 a, & 205. 
Zingis planispira Preston, also from S.W. Uganda, t.c. p. 185, 
pl. xxxil. fig. 16. 
LAROGIELLA VENATORIS, sp.n. (PI. I. figs. 22, 226, 22.) 
Shell somewhat depressedly turbinate, thin, yellowish brown ; 
whorls 57, regularly increasing, the last angled at the periphery 
and descending in front, marked with oblique growth-plicee ; 
suture impressed, almost imperceptibly margined below ; umbilicus 
moderately wide, deep, slightly overhung by the triangular, out- 
ward expansion of the columella margin; columella margin 
descending in a curve; labrum membranaceous; aperture com- 
pressedly ovate. 
Alt. 7-5, diam. maj. 12°5, diam. min. 10-25 mm. 
Aperture: alt. 5, diam. 5-5 mm. 
Hab. Larogi Hills, British East Africa, at an altitude of from 
6000 to 7000 feet. (A. Blayney Percival.) 
LAROGIELLA ANGULIFERA, sp. n. (PI. II. fig. 1.) 
Shell perforate, depressedly conic, thin, pale brown, painted 
with an indistinct, whitish, infrasutural band; whorls 5, the 
last descending in front, regularly increasing and angled at the 
periphery, marked with irregular, oblique, arcuate, transverse, 
crease-like riblets and showing traces of spiral whitish lines, 
