﻿Selection 
  of 
  Elementary 
  Species 
  95 
  

  

  the 
  race 
  above 
  its 
  average, 
  and 
  must 
  guard 
  

   constantly 
  against 
  the 
  regression 
  towards 
  this 
  

   average 
  which 
  usually 
  takes 
  place. 
  

  

  Hays 
  has 
  repeatedly 
  insisted 
  upon 
  the 
  prin- 
  

   ciple 
  of 
  the 
  choice 
  of 
  the 
  most 
  favorable 
  varie- 
  

   ties 
  as 
  the 
  foundation 
  for 
  all 
  experiments 
  in 
  

   improving 
  races. 
  He 
  asserts 
  that 
  half 
  the 
  bat- 
  

   tle 
  is 
  won 
  by 
  choosing 
  the 
  variety 
  which 
  is 
  to 
  

   serve 
  as 
  a 
  foundation 
  stock, 
  while 
  the 
  other 
  half 
  

   depends 
  upon 
  the 
  selection 
  of 
  parent-plants 
  

   within 
  the 
  chosen 
  variety. 
  Thus 
  the 
  choice 
  of 
  

   the 
  variety 
  is 
  the 
  first 
  principle 
  to 
  be 
  applied 
  in 
  

   every 
  single 
  case; 
  the 
  so-called 
  artificial 
  selec- 
  

   tion 
  takes 
  only 
  a 
  secondary 
  place. 
  Calling 
  all 
  

   minor 
  units 
  within 
  the 
  botanic 
  species 
  by 
  the 
  

   common 
  name 
  of 
  varieties, 
  without 
  regard 
  to 
  

   the 
  distinction 
  between 
  elementary 
  species 
  and 
  

   retrograde 
  varieties, 
  the 
  principle 
  is 
  designated 
  

   by 
  the 
  term 
  of 
  " 
  variety-testing. 
  " 
  This 
  test- 
  

   ing 
  of 
  varieties 
  is 
  now, 
  as 
  is 
  universally 
  known, 
  

   one 
  of 
  the 
  most 
  important 
  lines 
  of 
  work 
  of 
  the 
  

   agricultural 
  experiment 
  stations. 
  Every 
  state 
  

   and 
  every 
  region, 
  in 
  some 
  instances 
  even 
  the 
  

   larger 
  farms, 
  require 
  a 
  separate 
  variety 
  of 
  

   corn, 
  or 
  wheat, 
  or 
  other 
  crops. 
  They 
  must 
  be 
  

   segregated 
  from 
  among 
  the 
  hundreds 
  of 
  gen- 
  

   erally 
  cultivated 
  forms, 
  within 
  each 
  single 
  bo- 
  

   tanic 
  species. 
  Once 
  found, 
  the 
  type 
  may 
  be 
  

   ameliorated 
  according 
  to 
  the 
  local 
  conditions 
  

  

  