﻿PEOPAGATION 
  OF 
  FRESH-WATEK 
  MUSSELS. 
  

  

  11 
  

  

  a 
  mach 
  greater 
  number. 
  An 
  attachment 
  near 
  the 
  base 
  of 
  the 
  fila- 
  

   ment 
  giving 
  a 
  more 
  intimate 
  relation 
  with 
  the 
  host 
  may 
  insure 
  more 
  

   certain 
  survival 
  to 
  the 
  glochidium. 
  However, 
  the 
  cysts 
  I 
  have 
  

   examined 
  gave 
  no 
  evidence 
  of 
  serious 
  interference 
  with 
  circulation 
  in 
  

   the 
  filament, 
  so 
  it 
  looks 
  as 
  if 
  the 
  position 
  in 
  the 
  case 
  of 
  the 
  catfish 
  

   probably 
  would 
  not 
  make 
  much 
  difference 
  in 
  the 
  effect 
  on 
  the 
  host. 
  

  

  The 
  finding 
  of 
  glochidia 
  on 
  the 
  catfishes 
  is 
  of 
  interest, 
  since 
  this 
  fish 
  

   had 
  been 
  regarded 
  as 
  belonging 
  to 
  the 
  immime 
  class, 
  this 
  opinion 
  

   being 
  based 
  largely 
  on 
  the 
  results 
  of 
  artificial 
  infection. 
  The 
  habits 
  

   of 
  the 
  fish 
  as 
  a 
  bottom 
  feeder, 
  and 
  especially 
  as 
  a 
  voracious 
  eater 
  of 
  

   mussels, 
  would 
  make 
  it 
  seem 
  surprising 
  if 
  it 
  did 
  not 
  carry 
  the 
  glo- 
  

   chidia 
  of 
  some 
  species 
  of 
  mussel. 
  Forbes 
  and 
  Richardson 
  (1908), 
  in 
  

   examination 
  of 
  the 
  food 
  of 
  these 
  fish, 
  say: 
  

  

  Mollusks, 
  about 
  equally 
  large 
  water 
  snails, 
  and 
  large, 
  thin 
  clams 
  were 
  a 
  decidedly 
  

   important 
  element, 
  being 
  found 
  in 
  15 
  of 
  the 
  43 
  fishes. 
  They 
  amounted 
  to 
  15 
  per 
  cent 
  

   of 
  the 
  food 
  of 
  the 
  group, 
  and 
  several 
  specimens 
  had 
  little 
  or 
  nothing 
  else. 
  Notwith- 
  

   standing 
  the 
  number 
  of 
  bivalves 
  eaten 
  by 
  this 
  fish, 
  no 
  fragment 
  of 
  a 
  shell 
  was 
  ever 
  

   found 
  in 
  their 
  stomachs, 
  but 
  the 
  bodies 
  of 
  the 
  mollusks 
  seem 
  to 
  have 
  been 
  separated 
  

   while 
  yet 
  living 
  from 
  the 
  shells, 
  as 
  indicated 
  by 
  their 
  fresh 
  condition 
  and 
  by 
  the 
  fact 
  

   that 
  the 
  shell 
  muscles 
  were 
  scarcely 
  ever 
  present. 
  

  

  Table 
  1. 
  — 
  Artificial 
  Infections 
  with 
  Quadrula 
  pustulosa. 
  

  

  o 
  On 
  gills 
  and 
  barbels. 
  All 
  other 
  glochidia 
  were 
  attached 
  to 
  gills 
  only. 
  

  

  As 
  Q. 
  pustulosa 
  is 
  a 
  heavy-shelled 
  species 
  it 
  may 
  not 
  supply 
  the 
  

   catfish 
  with 
  food 
  by 
  way 
  of 
  returning 
  favors, 
  unless 
  the 
  fish 
  has 
  

   some 
  means 
  of 
  opening 
  the 
  heavy 
  shells. 
  However, 
  as 
  mussels 
  

   of 
  various 
  species 
  segregate 
  in 
  the 
  same 
  location, 
  forming 
  beds, 
  the 
  

   thinner-shelled 
  species 
  in 
  furnishing 
  food 
  to 
  the 
  fish 
  would 
  favor 
  tlie 
  

  

  