﻿470 
  Mr. 
  H. 
  B. 
  Preston 
  on 
  

  

  descending, 
  outwardly 
  reflexed 
  round 
  the 
  narrow 
  perforation 
  ; 
  

   aperture 
  inversely 
  auriform. 
  

  

  Alt. 
  10, 
  diam. 
  maj. 
  5 
  mm. 
  

  

  Aperture: 
  alt. 
  5, 
  diam. 
  2*5 
  mm. 
  

  

  Hab. 
  Between 
  Rumruti 
  and 
  Mount 
  Kenia, 
  British 
  East 
  

   Africa. 
  

  

  Cerastus 
  vobilis, 
  sp. 
  n. 
  (Fig. 
  20.) 
  

  

  Shell 
  acuminately 
  ovate, 
  scarcely 
  rimate, 
  somewhat 
  solid, 
  

   dark 
  flesh-coloured, 
  shading 
  to 
  a 
  paler 
  hue 
  on 
  the 
  last 
  whorl 
  ; 
  

   whorls 
  6, 
  rapidly 
  increasing, 
  the 
  apical 
  whorls 
  smooth, 
  

   the 
  remainder 
  decussately 
  sculptured 
  with 
  fine, 
  spiral 
  and 
  

   transverse 
  striae, 
  the 
  upper 
  whorls 
  also 
  being 
  rather 
  coarsely 
  

   obliquely 
  transversely 
  striate, 
  and 
  the 
  last 
  coarsely 
  malleated 
  ; 
  

   suture 
  impressed, 
  slightly 
  crenellate; 
  columella 
  rather 
  verti- 
  

   cally 
  descending, 
  outwardly 
  expanded 
  above, 
  a 
  faint 
  polished 
  

   callus 
  joining 
  it 
  with 
  the 
  margin 
  of 
  the 
  labrum 
  ; 
  labrum 
  

   thickened, 
  outwardly 
  expanded, 
  reflexed, 
  tinged 
  with 
  pale 
  

   reddish 
  brown 
  ; 
  aperture 
  inversely 
  auriform; 
  interior 
  of 
  shell 
  

   rich 
  reddish 
  brown. 
  

  

  Alt. 
  30, 
  diam. 
  maj. 
  21, 
  diam. 
  min. 
  17*5 
  mm. 
  

  

  Aperture: 
  alt. 
  135, 
  diam. 
  8\5 
  mm. 
  

  

  Hab. 
  Mount 
  Kenia, 
  at 
  an 
  altitude 
  of 
  6000-8000 
  feet, 
  

   British 
  East 
  Africa. 
  

  

  Jaminia 
  desiderata, 
  sp. 
  n. 
  (Fig. 
  21.) 
  

  

  Shell 
  small, 
  turbinate, 
  with 
  very 
  obtuse 
  apex, 
  reddish 
  

   brown 
  ; 
  whorls 
  5^, 
  rather 
  slowly 
  increasing, 
  moderately 
  

   convex, 
  the 
  last 
  ascending 
  in 
  front; 
  suture 
  well 
  impressed 
  ; 
  

   umbilicus 
  broad, 
  somewhat 
  deep, 
  partly 
  concealed 
  by 
  the 
  

   reflexion 
  of 
  the 
  columellar 
  margin; 
  columella 
  descending- 
  

   very 
  obliquely, 
  bearing 
  rather 
  interiorly 
  a 
  single 
  plait 
  ; 
  

   labrum 
  whitish, 
  sinuous, 
  reflexed, 
  projecting 
  inwardly 
  at 
  a 
  

   point 
  some 
  little 
  distance 
  below 
  its 
  junction 
  with 
  the 
  parietal 
  

   wall, 
  which 
  bears 
  a 
  weak, 
  very 
  oblique 
  lamella 
  ; 
  aperture 
  

   irregularly 
  quadrate. 
  

  

  Alt. 
  3, 
  diam. 
  maj. 
  2 
  mm. 
  

  

  Aperture 
  : 
  alt. 
  '75, 
  diam. 
  *5 
  mm. 
  

  

  Hab. 
  Mount 
  Kenia, 
  at 
  an 
  altitude 
  of 
  9000-10,000 
  feet, 
  

   British 
  East 
  Africa. 
  

  

  Fauxulus 
  duplicatus, 
  sp. 
  n. 
  (Fig. 
  22.) 
  

  

  Shell 
  small, 
  sinistral, 
  cylindrically 
  ovate, 
  rimate, 
  brown 
  ; 
  

   whorls 
  5, 
  the 
  first 
  four 
  regularly 
  increasing, 
  the 
  last 
  ascending 
  

  

  