﻿139 
  

  

  -extension 
  of 
  the 
  beds' 
  due 
  to 
  natural 
  unassisted 
  causes, 
  their 
  

   great 
  increase 
  in 
  area 
  during 
  the 
  last 
  thirty 
  years 
  must 
  be 
  as- 
  

   signed 
  to 
  other 
  agents. 
  

  

  The 
  diminution 
  of 
  the 
  number 
  of 
  oysters 
  may 
  be 
  affected 
  

   •by 
  several 
  natural 
  causes. 
  An 
  increased 
  deposit 
  of 
  earthy 
  

   or 
  vegetable 
  matter 
  upon 
  the 
  beds 
  would, 
  if 
  in 
  sufficient 
  

   quantities 
  to 
  bury 
  the 
  oyster, 
  effect 
  the 
  destruction 
  of 
  both 
  old 
  

   and 
  young. 
  No 
  such 
  deposit 
  has 
  been 
  noticed, 
  nor 
  could 
  it 
  well 
  

   occur 
  without 
  showing 
  its 
  presence 
  in 
  other 
  ways, 
  principally 
  

   by 
  changing 
  the 
  channels 
  and 
  causing 
  shoals 
  ; 
  but 
  no 
  such 
  

   changes 
  have 
  occurred, 
  my 
  investigation 
  showing 
  but 
  slight 
  de- 
  

   viations 
  in 
  either 
  channels, 
  shoals 
  or 
  character 
  of 
  the 
  bottom 
  

   from 
  that 
  established 
  by 
  the 
  first 
  hydrographic 
  survey 
  of 
  the 
  

   locality. 
  A 
  change 
  in 
  the 
  character 
  of 
  the 
  water 
  and 
  bottom, 
  

   which 
  would 
  probably 
  follow 
  a 
  change 
  of 
  channel, 
  and 
  might 
  

   ■occur 
  without 
  such 
  change, 
  might, 
  by 
  depriving 
  the 
  animals 
  of 
  

   their 
  proper 
  food, 
  cause 
  their 
  deterioration 
  and 
  destruction. 
  But 
  

   such 
  a 
  change, 
  though 
  it 
  would 
  certainly 
  diminish 
  the 
  numbers 
  

   on 
  the 
  beds, 
  would 
  do 
  so 
  suddenly 
  and 
  the 
  evil 
  effects 
  would 
  be 
  

   'noticed 
  in 
  the 
  oysters 
  remaining, 
  their 
  quality 
  and 
  flavor, 
  in- 
  

   deed, 
  their 
  vitality, 
  being 
  very 
  much 
  impaired. 
  No 
  such 
  impair- 
  

   ment 
  has 
  been 
  observed, 
  however, 
  the 
  oysters 
  being 
  larger 
  and 
  

   finer 
  than 
  when 
  the 
  beds 
  were 
  first 
  discovered. 
  That 
  fact 
  alone 
  

   will 
  eliminate 
  many 
  quantities 
  from 
  the 
  equation, 
  for 
  any 
  

   natural 
  cause 
  injurious 
  to 
  all 
  the 
  oysters 
  on 
  the 
  beds 
  would 
  be 
  

   evident 
  at 
  once 
  by 
  an 
  examination 
  of 
  those 
  found 
  at 
  present. 
  

   If, 
  however, 
  the 
  destruction 
  or 
  non-production 
  of 
  the 
  neces- 
  

   sary 
  number 
  of 
  young 
  is 
  accomplished 
  by 
  means 
  that 
  are 
  not 
  

   •harmful 
  to 
  the 
  mature 
  oyster, 
  a 
  cause 
  is 
  discovered 
  for 
  the 
  

   ■diminution 
  of 
  all 
  in 
  harmony 
  with 
  the 
  existing 
  facts. 
  Con- 
  

   sidering 
  first 
  the 
  destruction 
  of 
  young; 
  large 
  numbers, 
  immense 
  

   when 
  compared 
  witli 
  the 
  ordinary 
  production 
  of 
  other 
  ani- 
  

   mals, 
  are 
  without 
  doubt 
  naturally 
  destroyed 
  by 
  the 
  falling 
  of 
  

   the 
  "spat" 
  upon 
  unfavorable 
  grounds, 
  the 
  prevalence 
  of 
  heavy 
  

   freshets 
  which 
  would 
  drive 
  the 
  " 
  brood 
  " 
  into 
  the 
  Bay, 
  and 
  

   probably 
  cause 
  its 
  loss," 
  and 
  the 
  ravages 
  of 
  various 
  enemies. 
  

   But 
  all 
  these 
  causes 
  have 
  been 
  in 
  operation 
  continually 
  since 
  

   the 
  first 
  formation 
  of 
  the 
  beds, 
  and 
  the 
  animals 
  have 
  survived 
  

  

  