﻿PROPAGATION 
  OP 
  FRESH-WATER 
  MUSSELS. 
  25 
  

  

  tion 
  the 
  second 
  day 
  showed 
  many 
  glocliidia 
  encysted 
  upon 
  the 
  gills 
  of 
  

   the 
  sunfish, 
  but 
  only 
  one 
  or 
  two 
  on 
  the 
  bass 
  and 
  crappie. 
  The 
  third 
  

   day 
  they 
  were 
  still 
  in 
  good 
  condition 
  on 
  the 
  sunfish, 
  but 
  all 
  gone 
  on 
  the 
  

   others. 
  By 
  the 
  seventh 
  day 
  all 
  were 
  shed 
  by 
  the 
  sunfish. 
  Whether 
  

   the 
  parasitic 
  period 
  in 
  this 
  instance 
  was 
  completed 
  I 
  unfortunately 
  

   did 
  not 
  succeed 
  in 
  determining. 
  If 
  it 
  were, 
  the 
  period 
  is 
  a 
  brief 
  one 
  

   and 
  needs 
  further 
  testing. 
  Experiments 
  were 
  conducted 
  by 
  T. 
  

   Surber 
  with 
  this 
  mussel 
  at 
  the 
  Fairport 
  biological 
  station 
  in 
  1910. 
  

   The 
  following 
  fishes 
  were 
  used: 
  Micropterus 
  salmoides, 
  Pomoxis 
  

   annularis, 
  Aplodinotus 
  grunniens, 
  and 
  Lepomis 
  (sp, 
  ?). 
  No 
  implanta- 
  

   tion 
  at 
  any 
  point 
  on 
  or 
  in 
  the 
  body 
  was 
  observed, 
  but 
  free 
  (without 
  

   encystment) 
  glochidia 
  were 
  found 
  in 
  the 
  intestine 
  of 
  A. 
  grunniens 
  

   17^ 
  hours 
  after 
  exposure. 
  The 
  results 
  of 
  my 
  experiments 
  point 
  to 
  

   gill 
  infection 
  as 
  the 
  normal 
  method 
  for 
  this 
  mussel 
  and 
  to 
  good 
  chances 
  

   for 
  success 
  with 
  Lepomis 
  pallidus. 
  

  

  Propagation. 
  — 
  Propagation 
  of 
  this 
  valuable 
  mussel 
  at 
  present 
  

   would 
  probably 
  have 
  to 
  be 
  restricted 
  to 
  the 
  introduction 
  of 
  the 
  adult 
  

   mussel 
  in 
  new 
  territory. 
  The 
  success 
  of 
  this 
  method 
  can 
  not 
  be 
  pre- 
  

   dicted 
  with 
  any 
  degree 
  of 
  certainty 
  until 
  we 
  know 
  whether 
  the 
  host 
  

   (presumably 
  a 
  fish) 
  is 
  found 
  in 
  the 
  waters 
  where 
  introduction 
  is 
  

   attempted. 
  A 
  recent 
  report 
  of 
  Wilson 
  and 
  Danglade 
  (1912) 
  recom- 
  

   mends 
  the 
  introduction 
  of 
  this 
  mussel 
  into 
  the 
  rivers 
  of 
  Minnesota. 
  

   Very 
  practical 
  work 
  can 
  undoubtedly 
  be 
  done 
  along 
  the 
  line 
  of 
  exten- 
  

   sion 
  of 
  range 
  of 
  valuable 
  species, 
  but 
  it 
  would 
  be 
  obviously 
  impractical 
  

   to 
  do 
  this 
  without 
  a 
  more 
  certain 
  knowledge 
  than 
  we 
  have 
  at 
  present 
  

   of 
  the 
  life 
  history 
  of 
  this 
  species. 
  Take 
  for 
  example 
  the 
  case 
  of 
  the 
  

   niggerhead 
  mussel. 
  So 
  far 
  as 
  is 
  known, 
  it 
  is 
  dependent 
  entirely 
  upon 
  

   the 
  herring 
  (Pomolohus 
  chrysochloris) 
  for 
  propagation. 
  Introduction 
  

   into 
  waters 
  where 
  this 
  fish 
  was 
  absent 
  would 
  accordingly 
  be 
  certain 
  

   of 
  failure, 
  as 
  the 
  mussels 
  would 
  be 
  nonperpetuating. 
  I 
  have 
  men- 
  

   tioned 
  above 
  the 
  finding 
  of 
  many 
  unfertilized 
  eggs 
  in 
  the 
  marsupia 
  

   of 
  these 
  mussels. 
  In 
  the 
  examination 
  of 
  hundreds 
  of 
  shells 
  from 
  

   various 
  points 
  in 
  the 
  region 
  investigated 
  I 
  have 
  found 
  this 
  state 
  of 
  

   things 
  quite 
  general. 
  The 
  result 
  is 
  that 
  glochidia 
  are 
  difficult 
  to 
  

   obtain 
  except 
  in 
  small 
  numbers; 
  under 
  these 
  chcumstances 
  artificial 
  

   propagation 
  would 
  be 
  quite 
  impracticable. 
  

  

  The 
  Blue-point, 
  Quadrula 
  plicata 
  (Say). 
  [PL 
  ii, 
  fig. 
  17, 
  18.] 
  

  

  This 
  form 
  also 
  bears 
  the 
  name 
  of 
  "thi'ee-ridge." 
  It 
  is 
  at 
  present 
  

   one 
  of 
  the 
  most-used 
  shells 
  in 
  button 
  manufacture. 
  

  

  Distribution. 
  — 
  Western 
  New 
  York 
  to 
  Arkansas 
  and 
  Iowa, 
  Michigan 
  

   to 
  Alabama 
  and 
  Texas. 
  

  

  Habitat. 
  — 
  In 
  the 
  larger 
  rivers, 
  in 
  rather 
  deep 
  water, 
  generally 
  on 
  a 
  

   muddy 
  bottom 
  (Baker, 
  1898). 
  

  

  Juvenile. 
  — 
  I 
  have 
  found 
  this 
  species 
  with 
  several 
  others 
  in 
  the 
  

   artificial 
  ponds 
  at 
  the 
  Fairport 
  biological 
  station. 
  They 
  have 
  been 
  

  

  