﻿OYSTEE 
  INDUSTRY 
  OF 
  NORTH 
  CAROLINA. 
  263 
  

  

  consequent 
  reduction 
  and 
  the 
  final 
  disappearance 
  of 
  the 
  adjacent 
  

   oysters 
  on 
  shore. 
  The 
  growth 
  of 
  the 
  bar 
  continues, 
  finalh' 
  reaching 
  

   the 
  current 
  channel, 
  where 
  its 
  further 
  growth 
  results 
  in 
  forcing 
  the 
  

   current 
  to 
  bend 
  away 
  from 
  the 
  reef 
  and 
  cut 
  a 
  new 
  channel 
  farther 
  out. 
  

   The 
  currents 
  thus 
  no 
  longer 
  flow 
  straight 
  past 
  the 
  end 
  of 
  the 
  reef, 
  but 
  

   strike 
  it 
  at 
  an 
  angle 
  less 
  than 
  90-, 
  making 
  new^ 
  conditions, 
  under 
  which 
  

   the 
  most 
  rapid 
  growth 
  of 
  oysters, 
  at 
  right 
  angles 
  to 
  the 
  flow 
  of 
  the 
  

   displaced 
  currents, 
  is 
  no 
  longer 
  in 
  the 
  original 
  direction 
  of 
  the 
  reef. 
  

   A 
  branching 
  of 
  the 
  reef 
  at 
  its 
  end 
  is 
  thus 
  brought 
  about, 
  as 
  is 
  shown 
  

   in 
  figures 
  6 
  and 
  7. 
  

  

  As 
  the 
  reef 
  continues 
  to 
  grow 
  in 
  length, 
  its 
  damming 
  eli'ect 
  upon 
  the 
  

   volume 
  of 
  water, 
  which 
  must 
  twice 
  each 
  day 
  find 
  its 
  way 
  up 
  and 
  down 
  

   the 
  river, 
  increases, 
  and 
  there 
  comes 
  a 
  time 
  when 
  the 
  reef 
  is 
  no 
  longer 
  

   able 
  to 
  force 
  the 
  entire 
  stream 
  around 
  its 
  outer 
  end. 
  A 
  break 
  must 
  

   occur 
  at 
  some 
  point 
  in 
  the 
  reef, 
  and 
  in 
  nearly 
  all 
  cases 
  in 
  Newport 
  and 
  

   North 
  rivers 
  this 
  has 
  taken 
  place 
  at 
  a 
  point 
  a 
  few 
  yards 
  from 
  the 
  shore. 
  

   Reefs 
  originating 
  from 
  points 
  in 
  the 
  river 
  would 
  of 
  course 
  grow 
  from 
  

   both 
  ends, 
  and 
  a 
  break 
  in 
  their 
  length 
  would 
  not 
  be 
  likely 
  to 
  occur, 
  

   since 
  wide 
  open 
  ways 
  for 
  the 
  water 
  are 
  left 
  at 
  either 
  end. 
  

  

  Reefs 
  of 
  recent 
  formation 
  are 
  low 
  and 
  ver}' 
  narrow 
  in 
  proportion 
  to 
  

   their 
  length, 
  and 
  clusters 
  of 
  living 
  03^sters 
  are 
  found 
  evenly 
  distributed 
  

   o\'er 
  their 
  areas. 
  The 
  patches 
  of 
  oysters 
  in 
  the 
  center, 
  however, 
  in 
  

   time 
  are 
  covered 
  and 
  killed 
  b}'^ 
  the 
  sand, 
  mud, 
  and 
  shells 
  washed 
  up 
  

   and 
  deposited 
  upon 
  them 
  by 
  the 
  waves, 
  the 
  reefs 
  thus 
  gradually 
  

   becoming 
  higher 
  and 
  wider 
  (fig. 
  1). 
  With 
  the 
  accumulation 
  of 
  this 
  

   debris 
  year 
  by 
  year 
  the 
  high-water 
  mark 
  is 
  gradually 
  reached. 
  Succes- 
  

   sive 
  catches 
  of 
  spat, 
  which 
  spread 
  over 
  the 
  top 
  of 
  the 
  reef, 
  are 
  repeat- 
  

   edly 
  covered, 
  and 
  finallj^ 
  a 
  plane 
  is 
  reached 
  so 
  near 
  high-water 
  mark 
  

   that 
  the 
  period 
  of 
  time 
  during 
  which 
  the 
  oysters 
  are 
  covered 
  by 
  water 
  

   is 
  too 
  short 
  to 
  allow 
  them 
  to 
  collect 
  the 
  minimum 
  amount 
  of 
  food 
  

   required. 
  Examples 
  of 
  such 
  high, 
  permanently 
  dead 
  reefs 
  are 
  found 
  

   in 
  both 
  rivers. 
  They 
  are 
  conspicuous 
  objects 
  on 
  clear 
  days, 
  for 
  the 
  

   1>leached 
  shells 
  and 
  white 
  sand 
  of 
  which 
  they 
  are 
  composed 
  reflect 
  the 
  

   light 
  and 
  give 
  an 
  appearance 
  of 
  dazzling 
  whiteness. 
  

  

  Grass 
  finall}^ 
  takes 
  root 
  on 
  the 
  high 
  03'sterless 
  patches 
  on 
  the 
  old 
  

   formations, 
  and 
  then 
  the 
  "white" 
  reefs 
  begin 
  their 
  transformation 
  

   into 
  " 
  green" 
  reefs. 
  The 
  grassy 
  islands 
  found 
  in 
  various 
  places 
  in 
  the 
  

   rivers 
  are 
  usually 
  very 
  low 
  and 
  marsliy, 
  with 
  only 
  a 
  fringe 
  of 
  living- 
  

   oysters 
  around 
  them, 
  but 
  there 
  are 
  a 
  few 
  which, 
  in 
  addition 
  to 
  the 
  

   fringe 
  of 
  oysters, 
  have 
  a 
  hard 
  shelly 
  center. 
  This 
  character, 
  together 
  

   with 
  their 
  position 
  in 
  the 
  rivers, 
  suggests 
  their 
  probable 
  origin 
  from 
  

   oyster 
  reefs. 
  When 
  a 
  reef 
  is 
  young 
  and 
  low, 
  its 
  growth 
  in 
  length 
  is 
  

   rapid 
  until 
  the 
  limits 
  are 
  reached. 
  Its 
  upward 
  growth 
  is 
  restricted 
  to 
  

   the 
  height 
  at 
  which 
  the 
  oysters 
  are 
  able 
  to 
  catch 
  sufficient 
  food. 
  Each 
  

   reef, 
  however, 
  acts 
  as 
  a 
  dam 
  in 
  catching 
  and 
  holding 
  extensive 
  areas 
  

  

  