﻿372 
  ANNUAL 
  KEPOET 
  SMITHSONIAN 
  INSTITUTION, 
  1927 
  

  

  are 
  occasionally 
  taken 
  in 
  the 
  Ohio 
  River, 
  where 
  they 
  are 
  usually 
  

   recognized 
  as 
  rare 
  stragglers. 
  The 
  difference 
  in 
  physical 
  condi- 
  

   tions 
  is 
  probably 
  the 
  sole 
  cause 
  of 
  their 
  scarcity 
  in 
  the 
  Ohio 
  Basin. 
  

  

  Fig. 
  1. 
  — 
  Georgian 
  Bay 
  Lake 
  Herring, 
  Leucichthys 
  harengus 
  (Richardson). 
  Colling- 
  

  

  wood, 
  Georgian 
  Bay 
  

  

  Fig. 
  2. 
  — 
  Common 
  Lalte 
  Herring, 
  Leucichthys 
  artedi 
  (Le 
  Sueur). 
  Lake 
  Erie 
  at 
  

  

  Cleveland 
  

  

  '^-r^-'^v^ 
  

  

  Fig. 
  3. 
  — 
  Blackfln, 
  Leucichthys 
  nigripinnis 
  Gill. 
  Lake 
  Michigan, 
  Kenosha, 
  Wis. 
  

  

  The 
  similarity 
  of 
  the 
  fishes 
  in 
  the 
  different 
  streams 
  and 
  lakes 
  of 
  

   the 
  Great 
  Basin 
  of 
  Utah 
  is 
  doubtless 
  to 
  be 
  attributed 
  to 
  the 
  general 
  

   mingling 
  of 
  their 
  waters 
  which 
  took 
  place 
  during 
  and 
  after 
  the 
  

   glacial 
  epoch. 
  Since 
  that 
  period 
  the 
  climate 
  in 
  that 
  region 
  has 
  

  

  