﻿108 
  Elementary 
  Species 
  

  

  the 
  use 
  of 
  the 
  word 
  " 
  selection.' 
  This 
  word 
  

   was 
  used 
  by 
  Sheriff 
  as 
  seen 
  in 
  the 
  quotation 
  

   given, 
  and 
  it 
  was 
  obviously 
  designed 
  to 
  convey 
  

   the 
  same 
  idea 
  as 
  the 
  word 
  * 
  ' 
  lecta 
  : 
  ' 
  in 
  the 
  quo- 
  

   tation 
  from 
  Virgil. 
  It 
  was 
  a 
  choice 
  of 
  the 
  best 
  

   plants 
  from 
  among 
  known 
  mixed 
  fields, 
  but 
  the 
  

   chosen 
  individuals 
  were 
  considered 
  to 
  be 
  repre- 
  

   sentatives 
  of 
  pure 
  and 
  constant 
  races, 
  which 
  

   could 
  only 
  be 
  isolated, 
  but 
  not 
  ameliorated. 
  

   Selection 
  therefore, 
  in 
  the 
  primitive 
  sense 
  of 
  

   the 
  word, 
  is 
  the 
  choice 
  of 
  elementary 
  species 
  

   and 
  varieties, 
  with 
  no 
  other 
  purpose 
  than 
  that 
  

   of 
  keeping 
  them 
  as 
  pure 
  as 
  possible 
  from 
  the 
  

   admixture 
  of 
  minor 
  sorts. 
  The 
  Romans 
  at- 
  

   tained 
  this 
  end 
  only 
  imperfectly, 
  simply 
  be- 
  

   cause 
  the 
  laws 
  governing 
  the 
  struggle 
  for 
  life 
  

   and 
  the 
  competition 
  of 
  numerous 
  sorts 
  in 
  the 
  

   fields 
  were 
  unsuspected 
  by 
  them. 
  

  

  Le 
  Couteur 
  and 
  Sheriff 
  succeeded 
  in 
  the 
  solu- 
  

   tion 
  of 
  the 
  problem, 
  because 
  they 
  had 
  discovered 
  

   the 
  importance 
  of 
  isolation. 
  The 
  combination 
  

   of 
  a 
  careful 
  choice 
  with 
  subsequent 
  isolation 
  

   was 
  all 
  they 
  knew 
  about 
  it, 
  and 
  it 
  was 
  one 
  of 
  

   the 
  great 
  achievements 
  to 
  which 
  modern 
  agri- 
  

   culture 
  owes 
  its 
  success. 
  

  

  The 
  other 
  great 
  principle 
  was 
  that 
  of 
  Vil- 
  

   morin. 
  It 
  was 
  the 
  improvement 
  within 
  the 
  

   race, 
  or 
  the 
  " 
  amelioration 
  of 
  the 
  race 
  ; 
  as 
  it 
  

   was 
  termed 
  by 
  him. 
  It 
  was 
  introduced 
  into 
  

  

  