﻿LOBSTEE 
  AND 
  CLAM 
  INVESTIGATIONS. 
  . 
  183 
  

  

  On 
  fry 
  hatched 
  and 
  reared 
  at 
  Wickford: 
  

  

  Grammatophora 
  marina 
  (Lyngby) 
  Kiitzing. 
  

  

  Synedra 
  gallionii 
  Ehrenberg. 
  

  

  Synedra 
  affinis 
  Kiitzing. 
  

  

  Tabellaria 
  (Striatella) 
  unipunctata 
  Agardh. 
  

  

  Rhabdonema 
  arcuatum 
  (Lyngby) 
  Kiitzing. 
  

  

  Rhabdonema 
  adriaticuui 
  Kiitzing. 
  

  

  Cocconeis 
  scutellum 
  Ehrenberg. 
  

  

  Licmophora 
  tincta 
  Grunow. 
  

   On 
  fry 
  hatched 
  at 
  Woods 
  Hole 
  and 
  reared 
  at 
  Wickford: 
  

  

  Grammatophora 
  subtillissima 
  Bailey. 
  

  

  Synedra 
  gallionii 
  Ehrenberg. 
  

  

  Synedra 
  affinis 
  Kiitzing. 
  

  

  Rhabdonema 
  adriaticum 
  Kiitzing. 
  

  

  Rhabdonema 
  arcuatum 
  (Lyngby) 
  Kiitzing. 
  

  

  Tabellaria 
  (Striatella) 
  unipunctata 
  Agardh. 
  

  

  Nitzschia 
  longissima 
  (Brebisson) 
  Ralfs. 
  

  

  Licmophora 
  tincta 
  Grunow. 
  

  

  From 
  a 
  consideration 
  of 
  the 
  conditions 
  at 
  Wickford 
  it 
  seems 
  as 
  if 
  fry 
  

   reared 
  there 
  were 
  less 
  liable 
  to 
  infection 
  by 
  diatoms 
  than 
  those 
  reared 
  

   at 
  Woods 
  Hole, 
  even 
  though 
  the 
  same 
  species 
  of 
  diatoms 
  are 
  present 
  

   at 
  both 
  places. 
  The 
  fry 
  hatched 
  at 
  Woods 
  Hole 
  were 
  the 
  first 
  to 
  show 
  

   a 
  growth 
  of 
  diatoms 
  when 
  reared 
  at 
  Wickford, 
  and 
  perhaps 
  introduced 
  

   the 
  troublesome 
  species 
  in 
  large 
  numbers 
  to 
  the 
  rearing 
  bags 
  there. 
  

   It 
  is 
  noticeable 
  that 
  the 
  most 
  abundant 
  and 
  troublesome 
  species 
  at 
  

   Woods 
  Hole 
  was 
  the 
  eighth 
  most 
  abundant 
  species 
  on 
  fry 
  hatched 
  

   and 
  reared 
  at 
  Wickford. 
  

  

  The 
  character 
  of 
  the 
  material 
  of 
  which 
  the 
  rearing 
  bags 
  are 
  made 
  may 
  

   have 
  something 
  to 
  do 
  with 
  the 
  abundance 
  of 
  diatomaceous 
  growth, 
  not 
  

   only 
  on 
  the 
  bags, 
  but 
  also 
  on 
  the 
  fry 
  to 
  which 
  the 
  bags 
  so 
  readily 
  dis- 
  

   tribute 
  it. 
  It 
  is 
  certain 
  that 
  the 
  canvas 
  bags 
  used 
  at 
  Wickford 
  in 
  1902 
  

   did 
  not 
  become 
  foul 
  for 
  a 
  considerable 
  period, 
  while 
  the 
  scrim 
  bags 
  

   used 
  at 
  Woods 
  Hole 
  had 
  to 
  be 
  changed 
  every 
  few 
  days. 
  This 
  may 
  

   explain 
  the 
  later 
  appearance 
  of 
  the 
  growth 
  on 
  the 
  fry 
  reared 
  at 
  Wick- 
  

   ford 
  as 
  compared 
  with 
  those 
  reared 
  at 
  Woods 
  Hole. 
  

  

  Conditions 
  elsewhere. 
  — 
  Elsewhere 
  than 
  at 
  Woods 
  Hole 
  and 
  Wick- 
  

   ford 
  experimental 
  rearing 
  of 
  fry 
  has 
  not 
  been 
  tried 
  except 
  in 
  a 
  very 
  

   imperfect 
  way. 
  In 
  1900 
  some 
  preliminary 
  experiments 
  were 
  tried 
  at 
  

   Orrs 
  Island, 
  Maine, 
  and 
  Annisquam, 
  Mass. 
  In 
  the 
  former 
  locality 
  

   diatoms 
  were 
  abundant 
  on 
  the 
  fry; 
  at 
  the 
  latter 
  they 
  were 
  present 
  in 
  

   less 
  numbers. 
  The 
  higher 
  temperature 
  of 
  the 
  water 
  and 
  the 
  conse- 
  

   quent 
  more 
  rapid 
  growth 
  of 
  the 
  fry 
  probably 
  explains 
  the 
  compara- 
  

   tive 
  freedom 
  from 
  diatoms 
  at 
  Annisquam. 
  The 
  temperature 
  there 
  was 
  

   sometimes 
  as 
  high 
  as 
  76° 
  F., 
  and 
  the 
  lobsterling 
  (fourth) 
  stage 
  was 
  

   reached 
  in 
  ten 
  days. 
  

  

  