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  Probably 
  the 
  influence 
  of 
  changes 
  of 
  environment, 
  espe- 
  

   cially 
  of 
  density 
  and 
  temperature 
  of 
  tlie 
  water, 
  is 
  most 
  se- 
  

   verely 
  felt 
  by 
  the 
  embryos 
  when 
  in 
  their 
  free 
  swimming 
  state, 
  

   and, 
  in 
  connection 
  with 
  the 
  want 
  of 
  success 
  of 
  the 
  spatting 
  

   seasons 
  in 
  the 
  Sounds, 
  it 
  is 
  noticed 
  tlipt 
  the 
  temperature 
  curves 
  

   show 
  a 
  maximum 
  change 
  about 
  the 
  time 
  when 
  it 
  is 
  supposed 
  

   that 
  the 
  young 
  would 
  attach 
  in 
  largest 
  numbers, 
  or 
  about 
  

   the 
  period 
  when 
  they 
  were 
  swimming 
  about 
  in 
  the 
  water. 
  

  

  It 
  is 
  also 
  worthy 
  of 
  notice 
  that 
  Prof. 
  .Brooks, 
  about 
  tliis 
  

   time, 
  met 
  with 
  the 
  maximum 
  amount 
  of 
  success 
  in 
  his 
  efforts 
  

   to 
  artificially 
  raise 
  the 
  cmbrj'os. 
  

  

  In 
  consideration 
  of 
  the 
  foregoing, 
  I 
  am 
  of 
  the 
  opinion 
  that 
  

   the 
  success 
  or 
  failure 
  of 
  any 
  spatting 
  season 
  is 
  dependent 
  upon 
  

   the 
  equability 
  of 
  the 
  temperature, 
  and 
  that 
  the 
  higher 
  the 
  

   temperature 
  during 
  the 
  spring 
  months 
  the 
  earlier 
  the 
  advent 
  

   of 
  th3 
  spawning 
  season, 
  and 
  that 
  an 
  increased 
  temperature 
  

   will 
  also 
  hasten 
  the 
  development 
  of 
  the 
  spat, 
  and 
  of 
  the 
  young 
  

   oysters 
  after 
  they 
  have 
  become 
  attached. 
  

  

  I 
  also 
  infer 
  that 
  sudden 
  and 
  extensive 
  changes 
  of 
  density 
  

   will 
  likewise 
  affect 
  the 
  advent, 
  duration 
  and 
  success 
  of 
  the 
  

   spawning, 
  though 
  to 
  a 
  less 
  extent. 
  

  

  Subsequent 
  to 
  the 
  attachment 
  of 
  the 
  animal, 
  changes 
  of 
  the 
  

   conditions 
  surrounding 
  it 
  are 
  not 
  of 
  so 
  much 
  importance, 
  

   though 
  naturally 
  such 
  changes 
  will 
  more 
  severely 
  affect 
  the 
  

   delicate 
  organism 
  of 
  the 
  young 
  oyster 
  than 
  that 
  of 
  the 
  older 
  

   and 
  more 
  hardened 
  adult. 
  

  

  During 
  the 
  first 
  six 
  months 
  of 
  its 
  existence 
  the 
  oyster 
  is 
  ex- 
  

   posed 
  to 
  the 
  greatest 
  danger 
  from 
  the 
  numerous 
  enemies 
  

   which 
  surround 
  it. 
  The 
  thin, 
  'dencate 
  shells, 
  from 
  one-six- 
  

   teenth 
  of 
  an 
  inch 
  to 
  one 
  inch 
  in 
  diameter, 
  are 
  readily 
  bored 
  

   by 
  the 
  drills 
  or 
  torn 
  off 
  by 
  the 
  crabs, 
  and 
  the 
  immense 
  num- 
  

   bers 
  of 
  both 
  of 
  these 
  leave 
  no 
  room 
  to 
  doubt 
  their 
  destruc- 
  

   tive 
  effects. 
  The 
  inspection 
  of 
  the 
  spat 
  collectors 
  in 
  the 
  Big 
  

   Annemessex 
  River 
  shows 
  that 
  during 
  the 
  early 
  months 
  of 
  

   their 
  existence 
  about 
  50 
  per 
  cent, 
  of 
  the 
  young 
  oysters 
  are 
  de- 
  

   stroyed, 
  and 
  future 
  inspections 
  of 
  the 
  hurdle 
  will, 
  I 
  hope, 
  give 
  

   the 
  rate 
  of 
  decrease 
  in 
  other 
  periods 
  of 
  time. 
  

  

  Naturally, 
  as 
  the 
  animal 
  progresses, 
  it 
  becomes 
  more 
  hardy 
  

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