﻿110 
  Elementary 
  Species 
  

  

  appeared 
  some 
  years 
  later 
  at 
  the 
  International 
  

   Exhibition 
  of 
  London 
  in 
  1862. 
  Hence, 
  when- 
  

   ever 
  Darwin 
  speaks 
  of 
  selection, 
  ShirrefPs 
  use 
  

   of 
  the 
  word 
  may 
  as 
  well 
  be 
  meant 
  as 
  that 
  of 
  

   Vilmorin. 
  

  

  However, 
  before 
  going 
  deeper 
  into 
  such 
  the- 
  

   oretical 
  questions, 
  we 
  will 
  first 
  consider 
  the 
  

   facts, 
  as 
  given 
  by 
  Shirreff 
  himself. 
  

  

  During 
  the 
  best 
  part 
  of 
  his 
  life, 
  in 
  fact 
  during 
  

   the 
  largest 
  part 
  of 
  the 
  first 
  half 
  of 
  the 
  nine- 
  

   teenth 
  century, 
  Shirreff 
  worked 
  according 
  to 
  a 
  

   very 
  simple 
  principle. 
  When 
  quite 
  young 
  he 
  

   had 
  noticed 
  that 
  sometimes 
  single 
  plants 
  having 
  

   better 
  qualities 
  than 
  the 
  average 
  were 
  seen 
  

   in 
  the 
  fields. 
  He 
  saved 
  the 
  grains, 
  or 
  some- 
  

   times 
  the 
  whole 
  heads 
  of 
  such 
  plants 
  separate- 
  

   ly, 
  and 
  tried 
  to 
  multiply 
  them 
  in 
  such 
  man- 
  

   ner 
  as 
  to 
  avoid 
  intermixtures. 
  

  

  His 
  first 
  result 
  was 
  the 
  " 
  Mungoswell's 
  

   wheat." 
  In 
  the 
  spring 
  of 
  1819 
  he 
  observed 
  

   quite 
  accidentally 
  in 
  a 
  field 
  of 
  the 
  farm 
  of 
  that 
  

   name, 
  a 
  single 
  plant 
  which 
  attracted 
  his 
  atten- 
  

   tion 
  by 
  a 
  deeper 
  green 
  and 
  by 
  being 
  more 
  heav- 
  

   ily 
  headed 
  out. 
  Without 
  going 
  into 
  further 
  de- 
  

   tails, 
  he 
  at 
  once 
  chose 
  this 
  specimen 
  as 
  the 
  start- 
  

   ing 
  point 
  of 
  a 
  new 
  race. 
  He 
  destroyed 
  the 
  sur- 
  

   rounding 
  plants 
  so 
  as 
  to 
  give 
  it 
  more 
  space, 
  ap- 
  

   plied 
  manure 
  to 
  its 
  roots, 
  and 
  tended 
  it 
  with 
  

   special 
  care. 
  It 
  yielded 
  63 
  heads 
  and 
  nearly 
  

  

  