﻿THE 
  STORY 
  OF 
  A 
  PEARL. 
  43 
  

  

  lite 
  and 
  to 
  balls 
  of 
  iron 
  pyrites, 
  as 
  well 
  as 
  to 
  gall-stones 
  and 
  

   calculi 
  of 
  carbonate 
  of 
  lime. 
  Dr. 
  Lyster 
  Jameson* 
  has 
  recently 
  

   revived 
  the 
  opinion 
  of 
  De 
  Filippi,! 
  viz. 
  that 
  they 
  are 
  caused 
  by 
  

   parasites. 
  

  

  Linnaeus, 
  Chemnitz, 
  and 
  Olivi 
  knew 
  that 
  pearls 
  of 
  a 
  kind 
  

   could 
  be 
  produced 
  by 
  perforating 
  the 
  valves 
  of 
  the 
  Pearl-Mussels. 
  

   The 
  former, 
  indeed, 
  thus 
  thought 
  he 
  could 
  produce 
  pearls 
  at 
  will, 
  

   and, 
  it 
  is 
  said, 
  offered 
  to 
  publish 
  his 
  secret 
  for 
  the 
  benefit 
  of 
  the 
  

   State. 
  Bouchon-Brandely, 
  who 
  specially 
  studied 
  the 
  French 
  

   shell-beds 
  in 
  the 
  Tuamotu 
  group 
  of 
  isles*, 
  likewise 
  bored 
  the 
  large 
  

   Pearl-Oysters 
  (Pintadines), 
  fixing 
  the 
  rounded 
  piece 
  introduced 
  

   as 
  a 
  nucleus 
  by 
  a 
  wooden 
  pin. 
  It 
  was 
  covered 
  by 
  a 
  nacreous 
  

   layer 
  in 
  four 
  weeks. 
  \ 
  

  

  Pearls 
  are 
  found 
  in 
  many 
  shell-fishes, 
  not 
  only 
  in 
  bivalves, 
  

   where 
  they 
  are 
  best 
  known, 
  but 
  in 
  univalves. 
  Amongst 
  bivalves, 
  

   they 
  have 
  been 
  found 
  in 
  the 
  Common 
  Oyster 
  (Poli 
  procured 
  a 
  

   pearl 
  near 
  the 
  heart), 
  Pinna 
  nobilis§ 
  (brown, 
  black, 
  or 
  red 
  pearls), 
  

   Spondylus 
  gcederopus 
  (greenish 
  and 
  pale 
  rose-coloured 
  pearls), 
  

   Anomia 
  cepa 
  (purple 
  pearl), 
  and 
  Placuna 
  placenta 
  (the 
  Tamble- 
  

   gam 
  Pearl-Oyster, 
  also 
  called 
  Chinese 
  glass 
  or 
  window 
  Oyster, 
  

   the 
  shell 
  of 
  which 
  is 
  valuable). 
  Audouin, 
  in 
  1828, 
  found 
  a 
  minute 
  

   one 
  of 
  a 
  fine 
  white 
  colour, 
  but 
  not 
  iridescent, 
  in 
  Solen. 
  

  

  Amongst 
  univalves, 
  pearls 
  occur 
  in 
  Strombus 
  (' 
  Conch,' 
  of 
  the 
  

   West 
  Indies), 
  and 
  of 
  a 
  pretty 
  pink 
  colour 
  ; 
  Turbinella 
  (chank- 
  

   shell), 
  pale 
  red 
  pearls; 
  two 
  species 
  of 
  Turbo 
  ; 
  in 
  Haliotis, 
  and 
  

   others. 
  

  

  The 
  majority 
  of 
  the 
  valuable 
  marine 
  pearls 
  are 
  procured 
  from 
  

   the 
  various 
  species 
  of 
  Margaritifera 
  (Pearl-Oyster), 
  and 
  especially 
  

   from 
  the 
  Ceylonese 
  Pearl-Oyster 
  (M. 
  vulgaris), 
  a 
  species 
  exten- 
  

   sively 
  distributed 
  off 
  Ceylon, 
  Southern 
  India, 
  the 
  Maldive 
  Islands, 
  

   in 
  the 
  Persian 
  Gulf, 
  the 
  Eed 
  Sea, 
  Malay 
  Peninsula 
  and 
  Archi- 
  

   pelago, 
  Australia, 
  New 
  Zealand, 
  New 
  Guinea, 
  Japan, 
  and 
  East 
  

   Africa. 
  Moreover, 
  since 
  the 
  completion 
  of 
  the 
  Suez 
  Canal, 
  it 
  

   has 
  increased, 
  like 
  the 
  Sharks, 
  in 
  the 
  Mediterranean, 
  though 
  

  

  * 
  'Proceed. 
  Zool. 
  Soc' 
  March 
  4th, 
  1902. 
  

  

  f 
  "Sull' 
  OriginedellePerle," 
  'Est. 
  dalCimento,' 
  fasc. 
  iv. 
  Torino, 
  1852. 
  

  

  \ 
  ' 
  Eapport, 
  Peche 
  et 
  la 
  Culture 
  des 
  Huitres 
  Perlieres.' 
  Paris, 
  1885. 
  Vide 
  

   also 
  ' 
  Perles 
  et 
  Pintadines,' 
  par 
  M. 
  Picquenot. 
  Tahiti, 
  November, 
  1903. 
  

  

  § 
  Prof. 
  Herdman 
  found 
  the 
  same 
  form 
  of 
  Tetrarhynchus 
  larva 
  in 
  this 
  

   as 
  in 
  the 
  Pearl-Oyster, 
  

  

  E 
  2 
  

  

  