﻿MANUAL 
  OF 
  FISH-CULTURE. 
  207 
  

  

  a 
  glass 
  graduate. 
  The 
  dead 
  eggs 
  quickly 
  sink 
  and 
  the 
  quantity, 
  in 
  

   ounces, 
  is 
  noted 
  on 
  a 
  card 
  attached 
  to 
  each 
  box. 
  If 
  there 
  are 
  any 
  good 
  

   eggs 
  in 
  the 
  glass 
  they 
  are 
  saved; 
  the 
  spoiled 
  eggs 
  are 
  thrown 
  into 
  the 
  

   waste-trough. 
  Both 
  the 
  inner 
  box 
  and 
  the 
  trough 
  in 
  which 
  it 
  rests 
  are 
  

   thoroughly 
  washed 
  and 
  sponged 
  after 
  each 
  change. 
  

  

  When 
  the 
  inner 
  box 
  is 
  replaced 
  it 
  is 
  made 
  ready 
  for 
  the 
  eggs 
  to 
  be 
  

   transferred 
  from 
  the 
  third 
  box, 
  and 
  the 
  same 
  method 
  is 
  pursued 
  until 
  

   all 
  the 
  boxes 
  have 
  been 
  cleaned. 
  Eggs 
  recently 
  taken, 
  being 
  on 
  the 
  

   surface, 
  run 
  over 
  very 
  quickly, 
  5 
  or 
  10 
  minutes 
  usually 
  sufficing 
  for 
  

   the 
  transfer 
  of 
  a 
  box 
  of 
  400,000 
  eggs; 
  but 
  when 
  eggs 
  become 
  heavier, 
  

   as 
  a 
  result 
  of 
  development, 
  the 
  cleaning 
  takes 
  much 
  longer, 
  as 
  it 
  is 
  then 
  

   necessary 
  to 
  run 
  them 
  into 
  the 
  lower 
  part 
  of 
  the 
  box 
  (as 
  in 
  removing 
  

   dead 
  eggs) 
  and 
  to 
  dip 
  them 
  out, 
  care 
  being 
  taken 
  to 
  keep 
  the 
  lower 
  

   end 
  of 
  the 
  box 
  in 
  the 
  water 
  while 
  manipulating 
  them. 
  As 
  the 
  loss 
  of 
  

   eggs 
  has 
  ceased 
  by 
  the 
  time 
  they 
  reach 
  this 
  stage, 
  everything 
  in 
  the 
  

   box 
  may 
  be 
  dipped 
  over, 
  and 
  with 
  care 
  no 
  damage 
  is 
  done 
  the 
  eggs. 
  

  

  THE 
  FRY. 
  

  

  When 
  the 
  fry 
  first 
  hatch 
  they 
  are 
  much 
  curved 
  in 
  shape 
  and 
  show 
  

   but 
  little 
  vigor. 
  If 
  the 
  water 
  is 
  comparatively 
  warm 
  they 
  rapidly 
  

   straighten 
  out 
  and 
  become 
  stronger. 
  At 
  this 
  stage 
  they 
  float 
  at 
  the 
  sur- 
  

   face, 
  except 
  when 
  forced 
  about 
  by 
  the 
  current. 
  As 
  they 
  get 
  older 
  they 
  

   frecjuent 
  the 
  upper 
  water 
  less 
  and 
  if 
  kept 
  in 
  the 
  boxes 
  till 
  the 
  mouth 
  

   begins 
  to 
  functionate 
  most 
  of 
  them 
  remain 
  on 
  or 
  near 
  the 
  bottom. 
  

  

  As 
  soon 
  as 
  the 
  fiist 
  fry 
  in 
  a 
  given 
  box 
  make 
  their 
  appearance 
  the 
  

   eggs 
  are 
  all 
  ruufover 
  for 
  the 
  last 
  time. 
  As 
  the 
  fry 
  are 
  comparatively 
  

   delicate 
  they 
  are 
  handled 
  as 
  little 
  as 
  possible 
  and 
  with 
  great 
  care. 
  

  

  The 
  fry 
  are 
  planted 
  as 
  soon 
  as 
  practicable. 
  If 
  all 
  the 
  eggs 
  of 
  a 
  given 
  

   lot 
  have 
  not 
  hatched 
  it 
  is 
  better 
  to 
  plant 
  them 
  with 
  the 
  fry 
  rather 
  than 
  

   hold 
  the 
  latter 
  until 
  incubation 
  is 
  complete, 
  for 
  the 
  boxes 
  soon 
  beco-me 
  

   foul 
  from 
  the 
  accumulation 
  of 
  eggsht'lls 
  and 
  the 
  eggs 
  will 
  haitcJi 
  in 
  a 
  

   very 
  short 
  time, 
  especially 
  as 
  the 
  water 
  on 
  the 
  spawning-grounds 
  is 
  

   usually 
  3 
  or 
  4 
  degrees 
  warmer 
  than 
  the 
  water 
  in 
  the 
  hatchery. 
  

  

  When 
  the 
  fry 
  are 
  to 
  be 
  removed 
  from 
  the 
  boxes, 
  preparatory 
  to 
  plant- 
  

   ing, 
  a 
  ])lug 
  is 
  i)ut 
  in 
  the 
  current 
  hole 
  at 
  the 
  back 
  of 
  the 
  box, 
  and 
  in 
  a 
  

   short 
  time 
  most 
  of 
  them 
  will 
  come 
  to 
  the 
  surface. 
  They 
  are 
  then 
  dipj^ed 
  

   on* 
  and 
  put 
  in 
  transportation 
  cans. 
  About 
  200,000 
  fry 
  may 
  be 
  safely 
  

   carried 
  in 
  a 
  10 
  gallon 
  can. 
  Deposits 
  are 
  usually 
  made 
  on 
  the 
  natural 
  

   spawning-grounds. 
  

  

  