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  inferior 
  mantle 
  cavity, 
  which 
  had 
  evidently 
  been 
  drawn 
  

   in 
  by 
  t]w 
  iiiward 
  current. 
  It 
  is 
  plain 
  in 
  this 
  case 
  that 
  very 
  

   mild 
  means 
  may 
  become 
  effective 
  as 
  prehensih' 
  and 
  de- 
  

   structive 
  agents, 
  so 
  as 
  to 
  brinii' 
  remotely 
  related 
  ty})es 
  into 
  

   intimate 
  vital 
  I'elation. 
  Thoug-h 
  an 
  animal 
  may 
  })e 
  ap- 
  

   parently 
  invulnerab]*^)!! 
  account 
  of 
  the 
  effectiveness 
  of 
  

   its 
  covering, 
  it 
  cannot 
  emancipate 
  itself 
  from 
  the 
  a1)iding 
  

   struggle 
  it 
  has 
  to 
  make 
  to 
  obtain 
  food, 
  no 
  matter 
  how 
  pas- 
  

   sively 
  it 
  may 
  appear 
  to 
  conduct 
  itself. 
  The 
  oyster 
  has 
  

   such 
  a 
  chai-acter, 
  yet 
  it 
  has 
  been 
  apparent 
  from 
  what 
  has 
  

   been 
  observed 
  before, 
  tliat 
  it 
  is 
  entirely 
  dependent 
  for 
  a 
  

   vigorous 
  existence 
  upon 
  the 
  favorableness 
  of 
  surrounding 
  

   conditions. 
  The 
  beds 
  and 
  banks 
  in 
  a 
  true 
  sense 
  are 
  inter- 
  

   dependent 
  communities, 
  whose 
  vigor 
  may 
  no 
  doubt 
  be 
  

   impaired 
  by 
  the 
  removal 
  of 
  a 
  single 
  one 
  of 
  its 
  members. 
  

   Suppose 
  we 
  should 
  take 
  away 
  the 
  algae, 
  diatoms, 
  oyster 
  

   crabs, 
  vibriones, 
  bacteria, 
  infusoria, 
  in 
  fact 
  all 
  the 
  minute 
  

   life, 
  we 
  should 
  greatly 
  impair 
  if 
  not 
  destroy 
  the 
  vitality 
  

   of 
  the 
  beds. 
  While 
  it 
  is 
  true 
  that 
  many 
  of 
  even 
  the 
  

   smallest 
  forms 
  may 
  destroy 
  food 
  which 
  should 
  properly 
  

   be 
  consumed 
  by 
  the 
  oyster, 
  that 
  were 
  it 
  n< 
  t 
  for 
  the 
  pres- 
  

   ence 
  of 
  these 
  same 
  small 
  forms 
  some 
  dcstnictive 
  element 
  

   might 
  attain 
  such 
  a 
  development 
  as 
  to 
  be 
  more 
  injtiiious 
  

   still. 
  There 
  is 
  therefore 
  no 
  doubt 
  but 
  that 
  a 
  delicate 
  bal- 
  

   ance 
  of 
  })ower 
  is 
  maintained 
  by 
  these 
  rivals 
  which 
  is 
  best 
  

   for 
  the 
  health 
  of 
  the 
  community. 
  The 
  stability 
  of 
  ])erma- 
  

   nent 
  oyster 
  beds, 
  it 
  must 
  be 
  remembered, 
  furnishes 
  the 
  

   right 
  conditions 
  for 
  the 
  survival 
  of 
  many 
  types. 
  It 
  is 
  a 
  

   place 
  where 
  they 
  lind 
  both 
  a 
  home 
  and 
  plenty 
  of 
  food. 
  It 
  

   is 
  the 
  verj' 
  favorableness 
  offered 
  by 
  these 
  places 
  which 
  

   tends 
  to 
  induce 
  them 
  to 
  congregate 
  and 
  multiply, 
  and 
  it 
  

   becomes 
  a 
  serious 
  (piestion 
  whether 
  the 
  artificial 
  establish- 
  

   ment 
  of 
  banks 
  will 
  not 
  in 
  time 
  cause 
  the 
  proper 
  types 
  to 
  

   congregate 
  and 
  multii)ly 
  so 
  as 
  to 
  afford 
  the 
  needed 
  food 
  

   supply 
  for 
  the 
  oysters. 
  That 
  destructive 
  members 
  of 
  

   the 
  community 
  may 
  also 
  be 
  attracted 
  is 
  admitted, 
  but 
  if 
  

   the 
  beds 
  are 
  established 
  in 
  shallow 
  waters, 
  as 
  I 
  have 
  

  

  