﻿38 
  

  

  "of 
  elevations 
  witliiii, 
  wliirli 
  indicjited 
  points 
  wlieiv 
  the 
  

   ''intrndinii' 
  ])arasite 
  had 
  ]>een 
  kept 
  out 
  by 
  the 
  oyster 
  

   ''whicli 
  had 
  de|«osited 
  new 
  layers 
  of 
  ealrareons 
  matter 
  

   "at 
  these 
  places 
  so 
  as 
  to 
  give 
  rise 
  to 
  tlie 
  elevaHons 
  spoken 
  

   "of. 
  Besides 
  this, 
  the 
  inner 
  talde 
  iiad 
  heconie 
  so 
  weak- 
  

   "ened 
  at 
  the 
  insertion 
  of 
  tlie 
  adductor 
  nniscles 
  that 
  the 
  

   "animal 
  iii 
  closing 
  had 
  1)roken 
  a 
  part 
  of 
  it 
  loose, 
  the 
  

   "break 
  having 
  l>een 
  repaired 
  by 
  the 
  deposition 
  of 
  a 
  

   "brown 
  liorny 
  substance." 
  In 
  such 
  cases, 
  as 
  I 
  have 
  just 
  

   descril)ed, 
  it 
  is 
  clear 
  that 
  serious 
  damage 
  may 
  be 
  done 
  

   to 
  tlie 
  insertion 
  of 
  the 
  adductor 
  muscle, 
  the 
  perfect 
  in- 
  

   tegrity 
  of 
  wliich 
  and 
  power 
  to 
  close 
  the 
  valves 
  must 
  be 
  

   maintained, 
  or 
  there 
  is 
  a 
  possibility 
  that 
  the 
  oyster 
  may 
  

   be 
  invaded 
  ])y 
  some 
  hungry 
  carnivorous 
  neighbor 
  and 
  

   have 
  its 
  vitals 
  eaten 
  away 
  without 
  being 
  a]:)le 
  to 
  shut 
  out 
  

   the 
  intruder. 
  In 
  buying 
  ''i»lants" 
  it 
  would 
  probably 
  be 
  

   best 
  to 
  select 
  only 
  siicli 
  < 
  argoes 
  of 
  oysters 
  as 
  appear 
  to 
  

   have 
  clean 
  unbored 
  sliells. 
  or 
  siicli 
  as 
  are 
  not 
  "'worm- 
  

   eaten," 
  since 
  I 
  am 
  told 
  by 
  a 
  i>i'a('tical 
  oystei'man, 
  Mr. 
  ,J. 
  

   W. 
  Wrightson. 
  that 
  a 
  bed 
  once 
  x)lanted 
  with 
  oysters 
  

   which 
  ai'e 
  badly 
  infested 
  with 
  ('liona 
  or 
  the 
  boring 
  

   sponge, 
  are 
  apt 
  to 
  remain 
  so 
  for 
  some 
  time 
  and 
  that 
  the 
  

   beds 
  adjoining 
  ])ecame 
  infested 
  for 
  the 
  reason 
  that 
  the 
  

   embryo 
  sponges 
  Avhich 
  are 
  tlirown 
  off 
  in 
  large 
  nund>ers 
  

   from 
  tlve 
  infested 
  "'plants," 
  swim 
  about 
  in 
  the 
  water, 
  

   attach 
  themselves 
  to 
  other 
  oysters 
  commence 
  to 
  grow 
  

   and 
  to 
  bore. 
  

  

  The 
  proto/oan 
  fauna 
  of 
  St. 
  Jerome's 
  Creek 
  xu'esents 
  

   consideral>le 
  variety 
  ; 
  three 
  species 
  of 
  test-building 
  Co- 
  

   thurwia 
  were 
  noticed, 
  one 
  Vaginicola^ 
  three 
  species 
  of 
  

   VorticeUa 
  or 
  l)en-animalcules, 
  free 
  swimming 
  Evplotes^ 
  

   NassiilfLS 
  ; 
  of 
  the 
  latter 
  type 
  an 
  ex('eedingly 
  elongate 
  

   form 
  was 
  noticed, 
  with 
  a 
  body 
  almost 
  as 
  slender 
  as 
  a 
  

   thread-woi-m. 
  Monads 
  were 
  sometimes 
  noted 
  in 
  profu- 
  

   sion, 
  though 
  some 
  of 
  these 
  may 
  have 
  been 
  the 
  spores 
  of 
  

   algae. 
  Amoeboid 
  forms 
  were 
  very 
  few, 
  and 
  the 
  only 
  

   one 
  which 
  was 
  frequently 
  noticed 
  was 
  a 
  form 
  so 
  nearly 
  

  

  