﻿359 
  

  

  DIAGNOSES 
  OF 
  THEEE 
  NEW 
  OPERCULATE 
  LAND 
  SHELLS 
  FEOM 
  

   GEAND 
  CAYMAN 
  ISLAND. 
  

  

  By 
  H. 
  B. 
  Pkeston, 
  F.Z.S. 
  

  

  Bead 
  9th 
  June, 
  1911. 
  

  

  Neoctclotus 
  FONTIC0LUS, 
  n.sp. 
  

  

  Shell 
  rather 
  depressedly 
  turbinate, 
  solid, 
  in 
  dead 
  condition 
  grej-ish 
  

  

  white; 
  whorls 
  4|, 
  rather 
  rapidly 
  increasing, 
  the 
  last 
  descending 
  

  

  abruptly 
  and 
  disjunct 
  in 
  front, 
  very 
  coarsely 
  corrugated 
  throughout 
  ; 
  

  

  suture 
  impressed, 
  somewhat 
  crenellate, 
  broadly 
  margined 
  below, 
  

  

  especially 
  on 
  the 
  last 
  whorl 
  ; 
  umbilicus 
  surrounded 
  above 
  by 
  an 
  

   angular 
  overhanging 
  ridge, 
  rather 
  narrow, 
  very 
  deep 
  ; 
  labrum 
  greatly 
  

   receding 
  behind, 
  acute, 
  white 
  ; 
  aperture 
  subcircular. 
  Alt. 
  10 
  mm. 
  ; 
  

   diam. 
  maj. 
  14"25, 
  min. 
  11 
  mm. 
  Aperture: 
  alt. 
  10-5, 
  diam. 
  10'5 
  mm. 
  

   Mab. 
  — 
  Grand 
  Cayman 
  Island. 
  

  

  Choanopoma 
  Rosenbergianum, 
  n.sp. 
  

   Shell 
  somewhat 
  thin, 
  fusiformly 
  turbinate, 
  dark 
  greyish 
  brown 
  ; 
  

   remaining 
  whorls 
  o^, 
  convex, 
  sculptured 
  with 
  verj^ 
  closely 
  set. 
  

   slightly 
  oblique 
  transverse 
  costulae, 
  crossed 
  by 
  numerous 
  spiral 
  lirse 
  ; 
  

   suture 
  very 
  deeply 
  impressed, 
  scarcely 
  crenellate 
  ; 
  umbilicus 
  narrow, 
  

   deep, 
  coarsely 
  spirally 
  lirate 
  ; 
  labrum 
  cream-coloured, 
  continuous, 
  

   laminiferous, 
  the 
  inner 
  margin 
  erect 
  and 
  smooth, 
  the 
  outer 
  margin 
  

  

  moderatelj" 
  broadly, 
  outwardly 
  expanded, 
  and 
  somewhat 
  bluntly 
  serrate 
  

   at 
  the 
  edge; 
  aperture 
  subcircular; 
  interior 
  of 
  shell 
  pale 
  reddish 
  brown 
  ; 
  

   operculum 
  calcareous, 
  slightly 
  concave, 
  whitish 
  cream-coloured, 
  Avith 
  

   sub-central 
  brownish 
  nucleus. 
  Alt. 
  13 
  mm. 
  ; 
  diam. 
  maj. 
  10, 
  min. 
  

   7*5 
  mm. 
  Aperture 
  : 
  alt. 
  4, 
  diam. 
  3'5 
  mm. 
  

   Ilai. 
  — 
  Grand 
  Cayman 
  Island. 
  

  

  