﻿334 
  PROCEEDINGS 
  OF 
  THE 
  MALACOLOGICAL 
  SOCIETY. 
  

  

  growth 
  of 
  the 
  shell 
  ; 
  thus 
  eleven 
  may 
  be 
  counted 
  on 
  the 
  third 
  whorl, 
  

   while 
  there 
  are 
  only 
  fourteen 
  on 
  the 
  last 
  ; 
  these 
  ribs 
  are 
  prominent, 
  

   rounded, 
  and 
  not 
  continuous 
  from 
  wliorl 
  to 
  whorl. 
  The 
  earlier 
  

   whorls 
  slowly 
  increase, 
  but 
  at 
  the 
  antepenultimate 
  the 
  increase 
  

   becomes 
  more 
  rapid, 
  at 
  the 
  last, 
  however, 
  rapidly 
  contracting 
  in 
  

   the 
  descent 
  to 
  the 
  uuvaricosed 
  aperture. 
  The 
  base 
  is 
  sculptured 
  

   with 
  five 
  deep 
  incisions 
  separating 
  five 
  rounded 
  spiral 
  lirse. 
  There 
  is 
  

   no 
  umbilicus. 
  The 
  mouth 
  is 
  circular, 
  strongly 
  oblique 
  to 
  the 
  axis, 
  

   duplex, 
  but 
  not 
  varicose. 
  

  

  Length 
  about 
  3 
  mm., 
  breadth 
  l"5mm. 
  

  

  I 
  have 
  named 
  this 
  genus 
  after 
  my 
  friend 
  Mr. 
  Alex, 
  lleynell, 
  whose 
  

   help 
  with 
  regard 
  to 
  literature 
  is 
  again 
  acknowledged. 
  

  

  Anxietas 
  perplexa, 
  gen. 
  et 
  sp. 
  nov. 
  (PI. 
  XIII, 
  Fig. 
  5.) 
  

  

  Shell 
  minute, 
  conical, 
  base 
  flattened, 
  mouth 
  somewhat 
  quad- 
  

   rangular, 
  edges 
  thin, 
  columella 
  simple, 
  imperforate. 
  

  

  Type 
  : 
  Anxietas 
  perplexa, 
  sp. 
  nov. 
  

  

  This 
  peculiar 
  little 
  species 
  gives 
  no 
  clue 
  to 
  its 
  affinities 
  in 
  any 
  

   way, 
  and 
  I 
  place 
  it 
  in 
  tbe 
  Trochidse 
  with 
  considerable 
  reserve, 
  but 
  

   it 
  has 
  no 
  striking 
  feature 
  whereby 
  it 
  can 
  otherwise 
  be 
  determined. 
  

   Shell 
  conical, 
  top 
  flattened, 
  sides 
  rounded, 
  almost 
  unsculptured. 
  

   Colour 
  pale 
  brownish 
  yellow, 
  a 
  darker 
  line 
  at 
  the 
  sutures. 
  Five 
  

   whorls 
  may 
  be 
  counted, 
  of 
  which 
  the 
  apical 
  two 
  form 
  a 
  planate 
  

   nucleus, 
  the 
  succeeding 
  three 
  rather 
  rapidlj- 
  descending 
  but 
  tightly 
  

   wound 
  Avith 
  no 
  umbilicus. 
  Below 
  the 
  periphery 
  of 
  the 
  last 
  whorl 
  

   on 
  the 
  base 
  appear 
  a 
  couple 
  of 
  incised 
  lines 
  close 
  together, 
  but 
  no 
  

   other 
  sculpture 
  seems 
  present, 
  save 
  a 
  similar 
  incised 
  line 
  above 
  the 
  

   periphery, 
  which 
  is 
  seen 
  parallel 
  to 
  the 
  suture 
  on 
  the 
  three 
  post- 
  

   nuclear 
  whorls. 
  Columella 
  simple, 
  erect, 
  a 
  little 
  curved. 
  Aperture 
  

   oblique, 
  edges 
  thin. 
  Height 
  1"5 
  mm., 
  breadth 
  1 
  mm. 
  

  

  The 
  names 
  given 
  to 
  this 
  shell 
  express 
  my 
  opinion 
  regarding 
  it. 
  

   One 
  live 
  shell 
  was 
  recovered, 
  proving 
  that 
  it 
  lived 
  at 
  this 
  depth, 
  

   with 
  several 
  dead 
  ones. 
  It 
  resembles 
  no 
  juvenile 
  Trochoid 
  I 
  have 
  

   examined, 
  and 
  that 
  comprises 
  a 
  fair 
  number. 
  

  

  I 
  may 
  observe 
  that 
  these 
  descriptions 
  may 
  be 
  regarded 
  as 
  more 
  or 
  

   less 
  provisional, 
  subject 
  to 
  extension 
  upon 
  receipt 
  of 
  better 
  

   material 
  and 
  more 
  species. 
  In 
  anj 
  case 
  I 
  hope 
  to 
  furnish 
  with 
  

   any 
  further 
  detailed 
  account 
  additional 
  figures 
  elaborating 
  the 
  

   peculiar 
  points 
  of 
  the 
  species. 
  

  

  EXPLANATION 
  OF 
  PLATE 
  XIII. 
  

   Fig. 
  

  

  1. 
  Slierhornia 
  mirabilis, 
  gen. 
  and 
  sp. 
  n., 
  adult 
  from 
  above, 
  x 
  11. 
  p. 
  331. 
  

  

  2. 
  ,, 
  ,, 
  immature. 
  X 
  15. 
  

  

  3. 
  ,, 
  ,, 
  adult, 
  from 
  below. 
  

  

  4. 
  ,, 
  ,, 
  adult, 
  side 
  view. 
  

  

  5. 
  Anxietas 
  perplexa, 
  gen. 
  and 
  sp. 
  n. 
  x 
  18. 
  p. 
  334. 
  

  

  6. 
  Pickworthia 
  kirkpatricki, 
  gen. 
  and 
  sp. 
  n. 
  X 
  9. 
  p. 
  332. 
  

  

  7. 
  Reynellona 
  natalis, 
  gen. 
  and 
  sp. 
  n. 
  x 
  12. 
  p. 
  333. 
  

  

  8. 
  Pickioorthia 
  andreiosi, 
  sp.n. 
  x 
  14. 
  p. 
  333. 
  

  

  