﻿LOBSTER 
  AND 
  CLAM 
  INVESTIGATIONS. 
  193 
  

  

  (c) 
  Keeping 
  the 
  rearing 
  bags 
  free 
  from 
  diatoms 
  by 
  changing 
  the 
  

  

  material 
  of 
  which 
  they 
  are 
  composed, 
  by 
  coating 
  them 
  with 
  

   some 
  snbstance 
  which 
  will 
  not 
  permit 
  the 
  attachment 
  of 
  

   diatoms, 
  or 
  by 
  more 
  frequently 
  substituting 
  new 
  ones. 
  

  

  (d) 
  Regulation 
  of 
  the 
  amount 
  of 
  light 
  to 
  which 
  the 
  fry 
  are 
  exposed. 
  

  

  (e) 
  Hastening 
  the 
  development 
  of 
  the 
  fry 
  by 
  locating 
  the 
  rearing 
  

  

  apparatus 
  where 
  the 
  most 
  favorable 
  temperature 
  ma}^ 
  be 
  

  

  secured, 
  and 
  by 
  supplying 
  the 
  most 
  suitable 
  food. 
  

  

  4. 
  The 
  pathogenic 
  fungus, 
  though 
  known 
  to 
  be 
  extremely 
  fatal 
  and 
  

  

  disastrous 
  to 
  the 
  successful 
  rearing 
  of 
  fry 
  if 
  once 
  introduced 
  into 
  the 
  

  

  bags, 
  has 
  not 
  been 
  studied 
  sufficiently 
  to 
  warrant 
  any 
  suggestions 
  as 
  

  

  to 
  methods 
  for 
  its 
  prevention. 
  

  

  EXPLANATION 
  OF 
  PLATES. 
  

  

  PLATE 
  IV. 
  

  

  Figure 
  1. 
  The 
  diatom 
  Licmophora 
  tincta 
  Grunow, 
  growing 
  on 
  the 
  back 
  of 
  a 
  lobster 
  fry. 
  X 
  150. 
  

  

  Figure 
  2. 
  The 
  same, 
  showing 
  the 
  cellular 
  structure 
  of 
  the 
  frustule 
  and 
  the 
  formation 
  of 
  auxospores, 
  

   X200. 
  

  

  Figure 
  3. 
  Clean 
  lobster 
  eggs 
  and 
  egg.s 
  covered 
  with 
  a 
  growth 
  of 
  diatoms. 
  Natural 
  .size. 
  

  

  Figure 
  4. 
  Clean 
  lobster 
  fry 
  of 
  the 
  fourth 
  stage. 
  Natural 
  size. 
  

  

  Figure 
  5. 
  Lobster 
  fry 
  of 
  the 
  fourth 
  stage 
  covered 
  with 
  diatoms 
  and 
  a 
  tube-dwelling 
  amphipod, 
  

   Natural 
  size. 
  

  

  Figure 
  6. 
  Clean 
  lobster 
  fry 
  of 
  the 
  third 
  stage. 
  Natural 
  size. 
  

  

  Figure 
  7. 
  Lobster 
  fry 
  of 
  the 
  third 
  stage 
  covered 
  with 
  diatoms. 
  Natural 
  size. 
  

  

  Figure 
  1. 
  Claw 
  of 
  lobster 
  fry 
  of 
  the 
  third 
  stage 
  covered 
  with 
  diatoms. 
  X 
  50. 
  

  

  Figure 
  2. 
  Claws 
  of 
  lobster 
  fry 
  of 
  the 
  third 
  stage 
  covered 
  with 
  diatoms. 
  X 
  50. 
  

  

  Figure 
  3. 
  Clean 
  fry 
  of 
  the 
  first 
  stage. 
  X 
  10. 
  

  

  Figure 
  4. 
  Fry 
  of 
  the 
  first 
  stage 
  two 
  days 
  later 
  covered 
  with 
  diatoms. 
  X 
  10. 
  

  

  Figure 
  5. 
  Copepod, 
  Corynura 
  humpusii 
  Wheeler, 
  covered 
  with 
  diatom 
  Licmophora 
  tincta 
  Grunow. 
  

   X30. 
  

  

  Figure 
  6. 
  Young 
  Limulus 
  polyphemus 
  LinnsEus 
  covered 
  with 
  diatom 
  Rhabdonema 
  adriaticum 
  Kiit- 
  

   zing. 
  X1.5. 
  

  

  PLATE 
  VI. 
  

  

  Figure 
  1. 
  Posterior 
  segment 
  of 
  lobster 
  fry 
  of 
  third 
  stage 
  filled 
  with 
  fungus 
  mycelium. 
  X 
  25. 
  

   Figure 
  2. 
  Mycelium 
  of 
  fungus. 
  X 
  200. 
  

   Figure 
  3. 
  Colony 
  of 
  fungus 
  on 
  salt 
  water 
  agar. 
  X 
  25. 
  

   Figure 
  4. 
  Mycelium 
  of 
  fungus 
  showing 
  endospores. 
  X 
  250. 
  

   Figure 
  5. 
  Mycelium 
  of 
  fungus 
  broken 
  into 
  arthrospore.s 
  or 
  conidia. 
  X 
  250. 
  

   F. 
  C. 
  1903 
  13 
  

  

  