﻿CONTENTS. 
  

  

  Page. 
  

  

  Introduction 
  3 
  

  

  Physical 
  conditions 
  4 
  

  

  Pollution 
  of 
  the 
  Illinois 
  River 
  5 
  

  

  The 
  mussel 
  industry 
  7 
  

  

  Character 
  of 
  the 
  shells 
  8 
  

  

  Scientific 
  and 
  common 
  names 
  9 
  

  

  Commercial 
  appraisal 
  of 
  quantity 
  of 
  shells 
  10 
  

  

  Prices 
  of 
  shells 
  12 
  

  

  Principal 
  mussel 
  beds 
  13 
  

  

  Upper 
  river 
  13 
  

  

  Peoria 
  Lake 
  14 
  

  

  Lower 
  river 
  17 
  

  

  Tributaries 
  25 
  

  

  Dead 
  mussel 
  beds 
  26 
  

  

  Methods 
  of 
  the 
  Illinois 
  mussel 
  fishery 
  27 
  

  

  Crow-foot 
  bar 
  28 
  

  

  Dip 
  net 
  29 
  

  

  Legislation 
  30 
  

  

  The 
  pearls 
  of 
  the 
  Illinois 
  31 
  

  

  Finding 
  the 
  pearls 
  32 
  

  

  Classification 
  of 
  pearls. 
  33 
  

  

  Position 
  of 
  pearls 
  in 
  mussel 
  shells 
  34 
  

  

  Peeling 
  a 
  pearl 
  34 
  

  

  Crippled 
  shells 
  34 
  

  

  Quality 
  and 
  value 
  of 
  Illinois 
  pearls 
  35 
  

  

  Mussel 
  species. 
  37 
  

  

  Summary 
  and 
  conclusions 
  47 
  

  

  2 
  

  

  