﻿32 
  

  

  PROPAGATION 
  OF 
  FRESH-WATEK 
  MUSSELS. 
  

  

  Table 
  3. 
  — 
  Artificial 
  Infection 
  of 
  Quadrula 
  heros 
  Say. 
  

  

  Exper- 
  

   iments. 
  

  

  Fish. 
  

  

  No. 
  of 
  

   fish. 
  

  

  Olochid- 
  

   ium 
  re- 
  

   tained 
  

   until— 
  

  

  Period 
  on 
  fish. 
  

  

  En- 
  

   cysted. 
  

  

  Position. 
  

  

  Sept. 
  25 
  

  

  25 
  

  

  Oct. 
  1 
  

  

  Sept. 
  27 
  

  

  27 
  

  

  27 
  

  

  27 
  

  

  25 
  

  

  25 
  

  

  Oct. 
  7 
  

  

  30-34 
  

   30-34 
  

   30-34 
  

   30-34 
  

   30-32 
  

   30-35 
  

  

  30-35 
  

  

  30-34 
  

  

  30-35 
  

  

  34 
  

  

  P. 
  annularis. 
  

   P. 
  sparoides. 
  

   R. 
  chrysops. 
  . 
  

   M. 
  salriioides. 
  

   I. 
  punctatus. 
  

   A. 
  melas 
  

  

  L. 
  pallidas 
  ... 
  

   S. 
  canadense. 
  

   A. 
  grunniens 
  . 
  

   C. 
  difformis... 
  

  

  Sept. 
  26 
  

   Oct. 
  1 
  

   Oct. 
  6 
  

   Oct. 
  8 
  

   Feb. 
  7 
  

   Feb. 
  11 
  

  

  /Dec. 
  6 
  

  

  \Feb. 
  5 
  

  

  Oct. 
  5 
  

  

  Apr. 
  18 
  

  

  (Died.) 
  

  

  I 
  day 
  ■. 
  

  

  6 
  days 
  

  

  5 
  daj's 
  

  

  II 
  days 
  

  

  4 
  months 
  11 
  days 
  a. 
  

   4 
  months 
  15 
  days 
  " 
  . 
  

  

  i2 
  months 
  9 
  days 
  to 
  4 
  months 
  

  

  I 
  9 
  days. 
  

  

  10 
  days 
  

  

  6 
  months 
  11 
  days 
  « 
  

  

  No.. 
  

   Yes. 
  

   Yes. 
  

   Yes. 
  

   Yes. 
  

   Yes. 
  

  

  |Yes. 
  

   Yes. 
  

   Yes. 
  

   Yes. 
  

  

  Gill. 
  

  

  Do. 
  

  

  Do. 
  

  

  Do. 
  

   Fin. 
  

   Gill 
  and 
  

  

  fin. 
  

  

  Gill. 
  

  

  Do. 
  

   Fin. 
  

  

  Do. 
  

  

  « 
  Glochidia 
  remained 
  upon 
  the 
  fish 
  after 
  the 
  date 
  observed. 
  

  

  It 
  will 
  be 
  noted 
  that 
  both 
  gill 
  i. 
  d 
  fin 
  infection 
  persisted 
  more 
  than 
  

   four 
  months 
  on 
  the 
  catfishes, 
  Ictalurus 
  punctatus 
  and 
  Ameiurus 
  melas; 
  

   gill 
  iiifections 
  remained 
  upon 
  the 
  sunfish 
  over 
  two 
  months 
  (pi. 
  iv, 
  

   fig. 
  266). 
  In 
  these 
  cases 
  evidence 
  of 
  development 
  was 
  found, 
  but 
  not 
  

   determined 
  for 
  the 
  shorter 
  periods 
  of 
  11 
  days 
  or 
  less. 
  In 
  Aplodinotus, 
  

   fin 
  infections 
  remained 
  till 
  April, 
  more 
  than 
  six 
  months, 
  and 
  showed 
  

   considerable 
  development 
  at 
  the 
  time 
  of 
  examination. 
  

  

  The 
  indications 
  are 
  that 
  infection 
  takes 
  place 
  chiefly 
  during 
  the 
  

   autumn, 
  possibly 
  to 
  some 
  extent 
  in 
  winter 
  and 
  early 
  spring, 
  and 
  that 
  

   the 
  young 
  mussel 
  leaves 
  the 
  host 
  when 
  the 
  water 
  becomes 
  warmer 
  in 
  

   the 
  later 
  spring. 
  The 
  readiness 
  with 
  which 
  the 
  glochidia 
  become 
  

   attached 
  to 
  fish 
  in 
  the 
  autumn 
  would 
  indicate 
  that 
  this 
  is 
  a 
  natural 
  

   time 
  for 
  infection, 
  although 
  for 
  some 
  long-period 
  breeders 
  (Anodonta) 
  

   it 
  is 
  claimed 
  that 
  development 
  proceeds 
  during 
  the 
  winter 
  before 
  

   leaving 
  the 
  parent 
  gill 
  (Lillie, 
  1895). 
  Lillie 
  states 
  that 
  the 
  

   glochidia 
  are 
  carried 
  through 
  the 
  winter 
  and 
  are 
  extruded 
  finally 
  

   in 
  the 
  spring; 
  the 
  species 
  to 
  which 
  he 
  refers 
  is 
  Anodonta 
  cataracta. 
  

   Lefevre 
  and 
  Curtis 
  say 
  that 
  Anodontas 
  have 
  mature 
  glochidia 
  early 
  

   in 
  October. 
  An 
  experiment 
  performed 
  at 
  the 
  Fairport 
  laboratory 
  by 
  

   Messrs. 
  Clark 
  and 
  Surber 
  September 
  26, 
  1910, 
  with 
  A. 
  corpulenta 
  

   resulted 
  in 
  attachment 
  of 
  glochidia 
  upon 
  fish, 
  but 
  temporarily 
  only. 
  

   From 
  these 
  citations 
  it 
  would 
  seem 
  that 
  there 
  is 
  difference 
  of 
  obser- 
  

   vation 
  as 
  to 
  the 
  maturity 
  of 
  glochidia 
  in 
  the 
  genus 
  Anodonta. 
  There 
  

   may 
  be 
  a 
  considerable 
  difference 
  as 
  to 
  date 
  of 
  maturity 
  for 
  dift'erent 
  

   species 
  of 
  the 
  genus, 
  as 
  is 
  the 
  case 
  in 
  the 
  genus 
  Quadrula. 
  

  

  The 
  difference 
  in 
  duration 
  of 
  the 
  period 
  of 
  attachment 
  to 
  fislies 
  in 
  

   the 
  different 
  hosts 
  is 
  to 
  be 
  noted. 
  I 
  am 
  not 
  at 
  all 
  certain 
  of 
  the 
  

   explanation. 
  If, 
  as 
  reported 
  by 
  Schierholz 
  (1888) 
  and 
  Harms 
  (1907- 
  

   1909), 
  the 
  duration 
  of 
  tlie 
  parasitic 
  period 
  varies 
  inversely 
  as 
  the 
  

   temperature 
  of 
  the 
  water, 
  tliat 
  would 
  not 
  explain 
  the 
  liberation 
  of 
  

   glochidia 
  from 
  sunfisli 
  in 
  midwinter. 
  One 
  must 
  assume 
  a 
  difference 
  

   of 
  rate 
  for 
  different 
  liosts 
  or 
  tliat 
  development 
  was 
  incomplete 
  in 
  

   the 
  case 
  of 
  the 
  shorter 
  periods. 
  

  

  