﻿368 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  [16] 
  

  

  perature 
  of 
  the 
  water 
  resemble 
  each 
  other. 
  As 
  it 
  appears 
  that 
  the 
  

   glands 
  accomplish 
  their 
  germinative 
  evolution 
  in 
  a 
  few 
  weeks, 
  the 
  ejec- 
  

   tion 
  of 
  the 
  elements 
  of 
  reproduction 
  should 
  be 
  accomplished 
  in 
  a 
  com- 
  

   paratively 
  short 
  time. 
  The 
  observations 
  in 
  the 
  next 
  two 
  paragraphs 
  

   are 
  given 
  in 
  support 
  of 
  this 
  theory 
  : 
  

  

  The 
  spawning 
  oysters 
  gathered 
  and 
  brought 
  by 
  us 
  frorn 
  Fakarava 
  as 
  

   far 
  as 
  Papaetc, 
  had 
  all, 
  eight 
  days 
  after 
  their 
  arrival 
  in 
  the 
  last-men- 
  

   tioned 
  place, 
  discharged 
  the 
  sexual 
  products. 
  Towards 
  the 
  middle 
  of 
  

   the 
  mouth 
  of 
  July 
  we 
  noticed 
  in 
  the 
  island 
  of 
  Aratica, 
  that 
  the 
  oysters 
  

   of 
  the 
  lagoon 
  did 
  not 
  present 
  any 
  appearance 
  of 
  the 
  near 
  approach 
  of 
  

   generative 
  activity. 
  Five 
  weeks 
  later 
  the 
  oysters 
  of 
  this 
  same 
  lagoon 
  

   spawned. 
  

  

  I 
  have 
  made 
  similar 
  observations 
  at 
  Tahiti 
  and 
  Moorea, 
  all 
  proving 
  

   the 
  constant 
  activity 
  of 
  the 
  organs 
  of 
  reproduction. 
  The 
  fishermen 
  of 
  

   whom 
  I 
  made 
  inquiries 
  assured 
  me 
  that 
  the 
  oyster 
  propagates 
  its 
  species 
  

   every 
  year, 
  at 
  least 
  at 
  Tahiti, 
  Moorea, 
  and 
  in 
  the 
  Tuamotu 
  Islands. 
  

   It 
  is 
  possible 
  that 
  in 
  the 
  Gambier 
  Islands, 
  which 
  at 
  certain 
  periods 
  

   are 
  much 
  colder, 
  spawning 
  takes 
  place 
  only 
  at 
  certain 
  fixed 
  seasons. 
  

   The 
  fishermen 
  also 
  think 
  that 
  the 
  oysters 
  become 
  fertile 
  at 
  every 
  full 
  

   moon. 
  I 
  have 
  not 
  been 
  able 
  to 
  verify 
  the 
  truth 
  of 
  this 
  assertion, 
  as 
  far 
  

   as 
  the 
  pearl-oysters 
  are 
  concerned, 
  but 
  it 
  appears 
  to 
  be 
  generally 
  ad- 
  

   mitted 
  that 
  this 
  is 
  a 
  fact 
  as 
  regards 
  the 
  edible 
  oysters, 
  which 
  are 
  very 
  

   common 
  in 
  the 
  Society 
  Islands 
  (a 
  kind 
  of 
  Ostrca 
  xMcatula), 
  and 
  as 
  re- 
  

   gards 
  some 
  other 
  kinds 
  of 
  shell-fish. 
  The 
  emission 
  of 
  the 
  sexual 
  prod- 
  

   ucts 
  generally 
  took 
  place 
  at 
  the 
  waning 
  of 
  the 
  full 
  moon. 
  The 
  mother- 
  

   of-pearl 
  oyster 
  begins 
  to 
  spawn 
  from 
  the 
  year 
  following 
  that 
  of 
  its 
  

   birth. 
  

  

  During 
  my 
  stay 
  in 
  the 
  colony 
  of 
  Tahiti 
  I 
  made 
  a 
  certain 
  number 
  of 
  

   experiments 
  with 
  the 
  reproduction 
  and 
  raising 
  of 
  pearl-oysters, 
  which 
  

   were 
  accompanied 
  by 
  the 
  best 
  results. 
  I 
  proceeded 
  in 
  the 
  following* 
  

   manner: 
  

  

  At 
  the 
  very 
  outset 
  I 
  found 
  that 
  it 
  would 
  be 
  impossible 
  to 
  create 
  in 
  

   these 
  waters 
  oyster 
  pares 
  like 
  those 
  existing 
  on 
  the 
  shores 
  of 
  France 
  

   for 
  edible 
  oysters. 
  In 
  the 
  first 
  place, 
  the 
  pearl-oyster 
  cannot 
  live 
  an 
  

   independent 
  life 
  like 
  the 
  edible 
  oyster. 
  Once 
  detached 
  from 
  its 
  orig- 
  

   inal 
  collector, 
  it 
  immediately 
  needs 
  another 
  collector, 
  as 
  without 
  this 
  

   it 
  cannot 
  exist. 
  It 
  does 
  not 
  matter 
  what 
  may 
  be 
  the 
  nature 
  of 
  this 
  col- 
  

   lector 
  (wood, 
  iron, 
  stone, 
  or 
  brick), 
  the 
  oyster 
  will 
  at 
  once 
  adhere 
  to 
  it, 
  

   provided 
  it 
  is 
  a 
  body 
  which 
  has 
  the 
  power 
  of 
  resistance, 
  and 
  which 
  is 
  

   brought 
  in 
  close 
  proximity 
  to 
  the 
  threads 
  of 
  the 
  byssus. 
  It 
  would 
  be 
  a 
  

   grave 
  mistake 
  to 
  scatter 
  pearl-oysters 
  on 
  any 
  kind 
  of 
  sea-bottom, 
  and 
  

   expect 
  that 
  they 
  would 
  develop 
  there 
  like 
  edible 
  oysters, 
  as 
  the 
  result 
  

   would 
  most 
  certainly 
  be 
  a 
  failure. 
  If 
  such 
  an 
  oyster 
  falls 
  on 
  the 
  sand, 
  

   it 
  is 
  irrevocablv 
  doomed. 
  Pearl-oysters 
  are 
  not 
  provided 
  with 
  organs 
  

   of 
  locomotion 
  enabling 
  them 
  to 
  change 
  their 
  place. 
  And 
  how 
  could 
  the 
  

   oysters 
  be 
  found 
  again 
  among 
  the 
  net- 
  work 
  of 
  coral 
  which 
  covers 
  the 
  

  

  