﻿76 
  PliOCEEDINGS 
  OF 
  THE 
  MALACOLOGICAL 
  SOCIETY. 
  

  

  to 
  base, 
  nearly 
  an 
  inch 
  and 
  a 
  half, 
  with 
  a 
  diameter 
  of 
  an 
  inch; 
  

   whereas 
  the 
  specimen 
  called 
  microcephalus 
  has 
  only 
  2^ 
  whorls, 
  and 
  

   measures 
  only 
  about 
  three-eighths 
  of 
  an 
  inch. 
  Of 
  course, 
  there 
  are 
  

   many 
  intermediates, 
  differing 
  from 
  each 
  other 
  widely 
  in 
  form, 
  but 
  

   which 
  cannot 
  be 
  separated 
  on 
  any 
  specific 
  basis. 
  

  

  Magikis 
  costatus, 
  Sowerby, 
  Reeve, 
  Conch. 
  Icon., 
  vol. 
  xviii, 
  1872 
  

   {Magihis), 
  pi. 
  ii, 
  fig. 
  5. 
  

  

  Here 
  again 
  I 
  must 
  deny 
  the 
  validity 
  of 
  my 
  father's 
  species. 
  The 
  

   type 
  in 
  the 
  Eritish 
  Museum 
  has 
  rough 
  elevated 
  longitudinal 
  ridges, 
  

   giving 
  it 
  an 
  appearance 
  very 
  different 
  from 
  the 
  ordinary 
  M. 
  antiquus 
  ; 
  

   but 
  I 
  have 
  a 
  specimen 
  in 
  which 
  the 
  ridges, 
  though 
  not 
  quite 
  so 
  

   prominent, 
  are 
  well 
  developed, 
  and 
  others 
  in 
  which 
  the 
  ridges, 
  

   though 
  comparativelj' 
  faint, 
  are 
  plainly 
  discernible. 
  I 
  have 
  yet 
  

   other 
  specimens 
  exhibiting 
  very 
  close 
  sharp 
  transverse 
  ridges 
  without 
  

   the 
  slightest 
  trace 
  of 
  longitudinal 
  ridges. 
  

  

  The 
  following 
  I 
  take 
  to 
  be 
  simply 
  the 
  young 
  of 
  M. 
  antiqmcs 
  : 
  — 
  

  

  Genus 
  Leptoconchtjs, 
  Euppell, 
  Proc. 
  Zool. 
  Soc. 
  Lond., 
  ii, 
  1834, 
  p. 
  105. 
  

   Leptoconchis 
  ctimingi, 
  Deshayes, 
  in 
  Maillard, 
  I. 
  de 
  la 
  lleunion, 
  

  

  ed. 
  2, 
  He, 
  p. 
  125, 
  pi. 
  xii, 
  figs. 
  26, 
  27. 
  

   Leptoconchiis 
  cuviert, 
  Deshayes, 
  in 
  Maillard, 
  I. 
  de 
  la 
  Reunion, 
  

  

  ed. 
  2, 
  iiE, 
  p. 
  128, 
  pi. 
  xiii, 
  figs. 
  6, 
  7. 
  

   Zeptoco7ichus 
  elh'pticus, 
  Sowerby, 
  (Jenera 
  of 
  Shells; 
  Reeve, 
  Conch. 
  

  

  Icon., 
  vol. 
  xviii, 
  1872 
  (Magihis), 
  pi. 
  iii, 
  fig. 
  7. 
  

   Magilus 
  glohdosm, 
  Sowerby, 
  Reeve, 
  Conch. 
  Icon., 
  vol. 
  xviii, 
  1872 
  

  

  {Magilus), 
  pi. 
  iv, 
  fig. 
  10. 
  

   Magihis 
  peronii, 
  Lamarck, 
  Anim. 
  s. 
  Yert., 
  vol. 
  v, 
  1818, 
  p. 
  374. 
  

   Magilus 
  rostratus, 
  A. 
  Adams, 
  Ann. 
  Mag. 
  Nat. 
  Hist., 
  ser. 
  iii, 
  vol. 
  xiii, 
  

  

  1864, 
  p. 
  310. 
  

   Leptoconchus 
  ruppelUi, 
  Deshayes, 
  in 
  Maillard, 
  I. 
  de 
  la 
  Reunion, 
  ed. 
  2, 
  

  

  iiE, 
  p. 
  126, 
  pi. 
  xiii, 
  figs. 
  4-5 
  ; 
  Reeve, 
  Conch. 
  Icon., 
  vol. 
  xviii, 
  

  

  1872 
  {Magilus), 
  pi. 
  iv, 
  fig. 
  11. 
  

   Magilus 
  serratus, 
  Sowerby, 
  Reeve, 
  Conch. 
  Icon., 
  a'oI. 
  xviii, 
  1872 
  

  

  {Magilus), 
  pi. 
  iii, 
  fig. 
  8. 
  

   Leptoconchus 
  striatus, 
  Ruppell, 
  Trans. 
  Zool. 
  Soc. 
  Lond., 
  i, 
  1835, 
  

  

  p. 
  259, 
  pi. 
  XXXV, 
  figs. 
  9, 
  10. 
  

   Magilus 
  soliditisculus, 
  Sowerby, 
  Reeve, 
  Conch. 
  Icon., 
  vol. 
  xviii, 
  1872 
  

  

  {Magilus), 
  pi. 
  iv, 
  fig. 
  12 
  (Pease, 
  MS. 
  ? 
  in 
  Brit. 
  Mus.). 
  

   Of 
  these 
  forms 
  the 
  first 
  mentioned, 
  Z. 
  cumingi, 
  is 
  so 
  different 
  in 
  

   appearance 
  from 
  the 
  others 
  that 
  I 
  had 
  some 
  hesitation 
  in 
  including 
  

   it. 
  It 
  has 
  a 
  more 
  elevated 
  spire, 
  and 
  the 
  basal 
  keel 
  has 
  scarcely 
  

   begun 
  to 
  show, 
  but 
  having 
  met 
  with 
  a 
  developc-d 
  Magilus 
  of 
  the 
  same 
  

   form 
  I 
  hesitate 
  no 
  longer. 
  

  

  Genus 
  Coralliobia, 
  H. 
  & 
  A. 
  Adams, 
  Gen. 
  Shells, 
  vol. 
  i, 
  p. 
  138. 
  

  

  Tjrpe. 
  — 
  Concliolepas 
  {Coralliohia) 
  fimhriata, 
  A. 
  Adams, 
  Proc. 
  

  

  Zool. 
  Soc, 
  1852, 
  p. 
  93. 
  

   Magilus 
  fimhriattis, 
  Sow., 
  Reeve, 
  Conch. 
  Icon., 
  vol. 
  xviii, 
  1872 
  

  

  {Magilus), 
  pi. 
  iii, 
  fig. 
  9. 
  

  

  