﻿LOBSTER 
  AND 
  CLAM 
  INVESTIGATIONS. 
  207 
  

  

  late 
  as 
  September, 
  but 
  after 
  the 
  tirst 
  of 
  August 
  the 
  number 
  diminishes 
  

   rapid 
  l3^ 
  

  

  Figure 
  4: 
  represents 
  clams 
  taken 
  in 
  the 
  same 
  way 
  on 
  July 
  17. 
  There 
  

   still 
  appear 
  individuals 
  as 
  small 
  as 
  on 
  the 
  previous 
  date, 
  but 
  the}^ 
  are 
  

   less 
  numerous. 
  The 
  larger 
  ones 
  had 
  attained 
  a 
  length 
  of 
  about 
  13 
  mm. 
  

  

  On 
  July 
  27 
  another 
  lot 
  was 
  taken 
  and 
  is 
  represented 
  in 
  figure 
  6. 
  At 
  

   this 
  time 
  very 
  small 
  clams 
  still 
  seemed 
  to 
  be 
  making 
  their 
  appearance, 
  

   and 
  there 
  is 
  an 
  increase 
  in 
  the 
  maximum 
  size. 
  

  

  On 
  August 
  4 
  (tig. 
  6), 
  clams 
  but 
  recently 
  settled 
  to 
  the 
  bottom 
  were 
  

   not 
  numerous. 
  The 
  maximum 
  length 
  was 
  about 
  18 
  mm. 
  

  

  Figure 
  7 
  shows 
  individuals 
  taken 
  on 
  August 
  16. 
  There 
  were 
  still 
  

   found 
  at 
  this 
  time 
  a 
  very 
  few 
  that 
  had 
  recently 
  settled 
  to 
  the 
  bottom. 
  

   The 
  maximum 
  size 
  was 
  about 
  20 
  nun. 
  

  

  When 
  the 
  beds 
  in 
  this 
  bay 
  were 
  tirst 
  found 
  on 
  July 
  10, 
  there 
  were 
  

   alread}^ 
  so 
  many 
  empty 
  shells 
  lying 
  on 
  the 
  bottom 
  that 
  they 
  formed 
  a 
  

   white 
  line 
  which 
  could 
  easily 
  be 
  traced 
  for 
  some 
  distance 
  by 
  one 
  

   standing 
  on 
  the 
  high 
  bank. 
  Many 
  of 
  these, 
  however, 
  were 
  of 
  pre- 
  

   vious 
  generations. 
  As 
  time 
  went 
  on, 
  more 
  and 
  more 
  empty 
  shells 
  

   appeared, 
  until 
  in 
  August 
  the 
  surface 
  of 
  the 
  bottom 
  over 
  the 
  beds 
  

   was 
  covered 
  with 
  them. 
  

  

  It 
  appeared, 
  then, 
  that 
  even 
  well 
  within 
  the 
  breeding 
  season, 
  when 
  

   embr3'os 
  were 
  still 
  settling 
  to 
  the 
  bottom 
  in 
  great 
  numbers, 
  the 
  

   destruction 
  of 
  the 
  beds 
  had 
  begun. 
  On 
  July 
  10 
  numerous 
  dead 
  shells 
  

   were 
  found 
  in 
  the 
  bottom 
  as 
  well 
  as 
  on 
  its 
  surface. 
  Man}^ 
  of 
  these, 
  

   too, 
  were 
  clearly 
  not 
  shells 
  left 
  from 
  some 
  previous 
  season, 
  for 
  they 
  

   were 
  found 
  with 
  the 
  organic 
  matter 
  of 
  the 
  body 
  not 
  yet 
  decayed. 
  

   The 
  death 
  of 
  individuals 
  spread 
  rapidly, 
  until, 
  on 
  August 
  16, 
  a 
  square 
  

   foot 
  sometimes 
  yielded 
  no 
  more 
  than 
  half 
  a 
  dozen 
  live 
  clams. 
  By 
  

   September 
  1 
  practically 
  all 
  were 
  dead. 
  In 
  the 
  meantime 
  on 
  the 
  beach 
  

   above 
  the 
  mature 
  clams 
  were 
  holding 
  their 
  own 
  fairl}' 
  well, 
  but 
  it 
  is 
  a 
  

   signiticant 
  fact 
  that 
  digging 
  during 
  the 
  second 
  week 
  of 
  August 
  showed 
  

   that 
  man}^ 
  of 
  them 
  also 
  had 
  recently 
  died. 
  

  

  It 
  is 
  not 
  easy 
  to 
  explain 
  this 
  complete 
  destruction. 
  During 
  this 
  

   same 
  summer 
  Mead 
  was 
  studjnng 
  the 
  same 
  phenomenon 
  at 
  Wickford, 
  

   K. 
  I. 
  He 
  sa3^s: 
  "In 
  one 
  case 
  a 
  certain 
  point 
  of 
  the 
  shore 
  was 
  set 
  in 
  

   the 
  middle 
  of 
  July 
  as 
  thickl}^ 
  as 
  the 
  clams 
  could 
  burrow, 
  but 
  by 
  the 
  

   month 
  of 
  August 
  hardly 
  a 
  young 
  clam 
  could 
  be 
  found. 
  They 
  

   apparently 
  washed 
  out 
  or 
  were 
  covered 
  with 
  shifting 
  sand. 
  In 
  another 
  

   locality, 
  about 
  40 
  rods 
  from 
  the 
  last, 
  the 
  set 
  was 
  also 
  very 
  thick. 
  

   These 
  clams 
  continued 
  to 
  be 
  abundant 
  throughout 
  the 
  summer 
  and 
  

   autumn, 
  and, 
  though 
  meanwhile 
  they 
  w^ere 
  somewhat 
  thinned 
  out, 
  were 
  

   yet 
  very 
  numerous 
  on 
  December 
  4. 
  I 
  think 
  one 
  important 
  factor 
  in 
  

   their 
  wholesale 
  destruction 
  lies 
  in 
  the 
  fact 
  that 
  they 
  set 
  much 
  thicker 
  

   than 
  they 
  can 
  grow, 
  and 
  a 
  great 
  man}' 
  are 
  crowded 
  out." 
  

  

  It 
  has 
  been 
  stated 
  that 
  a 
  careful 
  examination 
  of 
  the 
  West 
  Falmouth 
  

  

  