﻿268 
  PROCEEDINGS 
  OF 
  THE 
  MALACOLOGICAL 
  SOCIETi'. 
  

  

  DESCEIPTION 
  OF 
  A 
  NEW 
  SPECIES 
  OF 
  HELICODONTA 
  FROM 
  

  

  TENERIFE. 
  

  

  By 
  G. 
  K. 
  GtJDE, 
  F.Z.S. 
  

  

  Bead 
  ISth 
  Januarij, 
  1911. 
  

  

  Among 
  a 
  number 
  of 
  laud 
  shells 
  collected 
  iu 
  1909 
  and 
  1910 
  by 
  

   Dr. 
  J. 
  H. 
  Salter 
  iu 
  Tenerife, 
  and 
  submitted 
  to 
  me 
  for 
  identification, 
  

   a 
  form 
  was 
  observed 
  which 
  appears 
  to 
  be 
  uudescribed. 
  

  

  Compared 
  with 
  Helicodonta 
  fortunata, 
  Shutt., 
  its 
  nearest 
  ally, 
  the 
  

   new 
  species 
  is 
  at 
  once 
  separated 
  by 
  its 
  more 
  elevated 
  spire 
  and 
  

   narrower 
  umbilicus; 
  the 
  whorls 
  are 
  also 
  more 
  convex, 
  both 
  above 
  

   and 
  below, 
  whilst 
  the 
  peripheral 
  keel 
  is 
  not 
  pinched 
  as 
  in 
  that 
  

   species 
  ; 
  the 
  costulse 
  are 
  much 
  less 
  pronounced, 
  and 
  the 
  columellar 
  

   margin 
  of 
  the 
  peristome 
  is 
  more 
  curved. 
  The 
  principal 
  feature, 
  

   however, 
  iu 
  which 
  it 
  differs 
  lies 
  in 
  the 
  granules, 
  which 
  are 
  lacking 
  in 
  

   //. 
  fortunata. 
  

  

  In 
  appending 
  a 
  diagnosis 
  of 
  the 
  new 
  species 
  1 
  have 
  much 
  pleasure 
  

   in 
  associating 
  with 
  it 
  the 
  name 
  of 
  its 
  discoverer. 
  

  

  Helicodonta 
  Salteei, 
  n.sp. 
  

  

  Shell 
  moderately 
  umbilicated, 
  conoid, 
  solid, 
  light 
  rufous 
  above, 
  

   paler 
  below, 
  especially 
  towards 
  the 
  umbilicus 
  ; 
  nepionic 
  whorls 
  

   finely 
  granulated, 
  the 
  remainder 
  closely 
  covered 
  with 
  fine 
  curved 
  

   riblets, 
  and 
  densely 
  infested 
  with 
  granules 
  arranged 
  in 
  quincunx 
  

   above, 
  but 
  somewhat 
  irregularly 
  below. 
  Spire 
  pyramidal 
  ; 
  apex 
  

   acute 
  ; 
  suture 
  linear. 
  AVhorls 
  5, 
  slightly 
  flattened 
  above, 
  convex 
  

   1)elow, 
  obtusely 
  carinated 
  at 
  the 
  periphery, 
  and 
  obtusely 
  angulated 
  

   round 
  the 
  umbilicus, 
  increasing 
  regularly, 
  the 
  last 
  nearly 
  twice 
  as 
  

  

  wide 
  as 
  the 
  penultimate, 
  shortly 
  deflexed 
  in 
  front, 
  and 
  slightly 
  

   constricted 
  behind 
  the 
  peristome. 
  Aperture 
  semi-rotundate, 
  oblique, 
  

   margins 
  approaching, 
  united 
  by 
  a 
  thin 
  callus 
  on 
  the 
  parietal 
  wall. 
  

   Peristome 
  scarcely 
  thickened, 
  reflexed, 
  whitish, 
  upper 
  margin 
  slightly 
  

   curved, 
  basal 
  rounded, 
  columellar 
  ascending, 
  and 
  slightly 
  dilated. 
  

   Umbilicus 
  moderately 
  wide 
  and 
  deep, 
  showing 
  a 
  portion 
  of 
  the 
  

   penultimate 
  whorl. 
  Diam. 
  maj. 
  12, 
  niin. 
  10-5 
  mm.; 
  alt. 
  6 
  mm. 
  

   Hab. 
  — 
  Tenerife, 
  Canary 
  Islands. 
  Type 
  in 
  my 
  collection. 
  

  

  