﻿286 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  

  

  storms, 
  by 
  cold 
  rains, 
  and 
  by 
  sudden 
  falls 
  in 
  temperature, 
  and 
  the 
  

   prevalence 
  of 
  such 
  weather 
  during' 
  the 
  spawning 
  season 
  must 
  have 
  an 
  

   imjwrtant 
  effect 
  uiion 
  the 
  set 
  of 
  spat. 
  

  

  FOOD. 
  

  

  The 
  oyster 
  feeds 
  upon 
  both 
  animal 
  and 
  vegetable 
  food, 
  the 
  particles 
  of 
  

   which 
  are 
  of 
  microscopic 
  dimensions. 
  The 
  fry 
  and 
  young 
  spat 
  consume 
  

   relatively 
  large 
  quantities 
  of 
  bacteria 
  and 
  monads, 
  among 
  the 
  most 
  

   minute 
  organisms 
  known 
  to 
  microscopists. 
  According 
  to 
  Dr. 
  Eyder: 
  

  

  Many 
  of 
  the 
  food 
  balls 
  found 
  in 
  the 
  intestine 
  of 
  the 
  recently 
  attached 
  sjiat 
  will 
  

   measure 
  under 
  TnTVurr 
  inch 
  in 
  diameter. 
  The 
  cavity 
  of 
  the 
  little 
  creature's 
  stomach 
  

   measures 
  only 
  Ymo 
  inch. 
  Yet 
  in 
  this 
  minute 
  digestive 
  cavity 
  the 
  food 
  is 
  actually 
  

   found 
  rotating 
  in 
  the 
  form 
  of 
  minute 
  rounded 
  and 
  oval 
  bodies, 
  which 
  are 
  kept 
  in 
  

   motion 
  by 
  the 
  action 
  of 
  the 
  cilia 
  which 
  line 
  the 
  stomach. 
  That 
  these 
  bodies 
  must 
  

   have 
  been 
  of 
  about 
  the 
  size 
  noted 
  when 
  they 
  were 
  originally 
  swallowed 
  and 
  as 
  seen 
  

   rotating 
  in 
  the 
  stomach 
  is 
  evident 
  from 
  the 
  fact 
  that 
  the 
  young 
  oysters, 
  like 
  the 
  

   adults, 
  are 
  wholly 
  without 
  teeth 
  or 
  triturating 
  organs 
  of 
  any 
  Rind. 
  

  

  This 
  minute 
  kind 
  of 
  vegetable 
  and 
  animal 
  food 
  is 
  found 
  more 
  or 
  less 
  abundantly 
  

   in 
  all 
  sea 
  water, 
  and 
  is 
  especially 
  abundant 
  during 
  the 
  spawning 
  season, 
  when 
  the 
  

   decomposition 
  and 
  disintegration 
  of 
  all 
  kinds 
  of 
  minute 
  organic 
  debris 
  lloating 
  about 
  

   in 
  the 
  water 
  is 
  in 
  rapid 
  progress, 
  owing 
  to 
  the 
  prevalent 
  high 
  temperature 
  of 
  the 
  

   air 
  and 
  water. 
  It 
  is, 
  therefore, 
  probable 
  that 
  very 
  few 
  otherwise 
  suitable 
  locations 
  

   exist 
  where 
  it 
  is 
  not 
  possible 
  to 
  find 
  an 
  abundance 
  of 
  the 
  proper 
  sort 
  of 
  food 
  for 
  the 
  

   oyster 
  during 
  its 
  very 
  earliest 
  stages 
  of 
  growth. 
  

  

  The 
  food 
  of 
  the 
  slightly 
  more 
  advanced 
  spat 
  and 
  the 
  adults 
  is 
  found 
  to 
  consist 
  of 
  

   diatoms, 
  rhizopods, 
  infusoria 
  of 
  all 
  kinds, 
  monads, 
  spores 
  of 
  alga-, 
  pollen 
  grains 
  

   blown 
  from 
  trees 
  and 
  plants 
  on 
  shore, 
  their 
  own 
  larvai 
  or 
  fry, 
  as 
  well 
  as 
  that 
  of 
  many 
  

   other 
  moUusks, 
  of 
  bryozoa 
  and 
  minute 
  embryos 
  of 
  polyps 
  and 
  worms, 
  together 
  with 
  

   other 
  fragments 
  of 
  animal 
  or 
  vegetable 
  origin, 
  and 
  sometimes 
  even 
  minute 
  crusta- 
  

   ceans. 
  In 
  variety 
  of 
  food 
  the 
  oyster, 
  therefore, 
  has 
  a 
  wide 
  range 
  of 
  choice. 
  There 
  

   are 
  also 
  few 
  locations 
  otherwise 
  well 
  adapted 
  which 
  will 
  not 
  supply 
  an 
  abundance 
  

   of 
  food 
  for 
  the 
  animal, 
  which, 
  it 
  is 
  to 
  be 
  remembered, 
  captures 
  and 
  hoards 
  millions 
  

   of 
  these 
  minute 
  plants 
  and 
  creatures 
  in 
  its 
  stomach, 
  where 
  they 
  are 
  digested 
  and 
  

   incorporated 
  into 
  its 
  own 
  organization. 
  It 
  therefore 
  follows 
  that 
  wheu 
  we 
  eat 
  an 
  

   oyster 
  we 
  are 
  consuming 
  what 
  it 
  required 
  millions 
  of 
  the 
  minutest 
  organisms 
  in 
  the 
  

   world 
  to 
  nourish. 
  The 
  oyster 
  is 
  consequently 
  a 
  sort 
  of 
  living 
  storehouse 
  for 
  the 
  

   incorporation 
  and 
  appropriation 
  of 
  the 
  minute 
  life 
  of 
  the 
  sea, 
  which 
  could 
  never 
  be 
  

   rendered 
  tributary 
  to 
  the 
  food 
  supply 
  of 
  mankind 
  in 
  any 
  other 
  way 
  except 
  through 
  

   the 
  action, 
  growth, 
  and 
  organization 
  of 
  this 
  mollusk.* 
  

  

  The 
  quantity 
  of 
  young 
  oysters 
  consumed 
  by 
  the 
  adults 
  is 
  doubtless 
  

   enormous, 
  200 
  fry 
  having 
  been 
  found 
  in 
  the 
  stomach 
  of 
  single 
  individ- 
  

   uals. 
  Not 
  only 
  the 
  free-swimming 
  fry, 
  but 
  eggs 
  and 
  spermatozoa 
  are 
  fed 
  

   upon, 
  and 
  an 
  insight 
  Is 
  here 
  gained 
  into 
  the 
  ultimate 
  fate 
  of 
  some 
  of 
  the 
  

   vast 
  numbers 
  of 
  genital 
  elements 
  which 
  the 
  parents 
  shed 
  into 
  the 
  water. 
  

  

  While 
  the 
  oyster 
  feeds 
  upon 
  both 
  plant 
  and 
  animal 
  organisms, 
  it 
  

   must 
  be 
  remembered 
  that 
  it 
  is 
  primarily 
  dependent 
  upon 
  the 
  former. 
  

   That 
  not 
  only 
  is 
  the 
  major 
  portion 
  ot 
  the 
  food 
  of 
  the 
  oyster 
  itself 
  of 
  

   vegetable 
  origin, 
  but 
  the 
  minute 
  animal 
  forms 
  are 
  dependent 
  for 
  their 
  

   sustenance 
  upon 
  the 
  plants 
  and 
  are 
  not 
  to 
  be 
  found 
  in 
  abundance 
  far 
  

   removed 
  from 
  them. 
  

  

  * 
  Rept. 
  U. 
  S. 
  F. 
  C. 
  1885, 
  pp. 
  387-388. 
  

  

  