﻿98 
  Elementary 
  Species 
  

  

  of 
  course 
  not 
  applicable 
  to 
  the 
  wheat 
  of 
  Jersey 
  

   alone. 
  The 
  common 
  cultivated 
  sorts 
  of 
  wheat 
  

   and 
  other 
  grains 
  were 
  mixtures 
  then 
  as 
  they 
  

   are 
  even 
  now. 
  Improved 
  varieties 
  are, 
  or 
  at 
  

   least 
  should 
  be, 
  in 
  most 
  cases 
  pure 
  and 
  uniform, 
  

   but 
  ordinary 
  sorts, 
  as 
  a 
  rule, 
  are 
  mixtures. 
  

   Wheat, 
  barley 
  and 
  oats 
  are 
  self-fertile 
  and 
  do 
  

   not 
  mix 
  in 
  the 
  field 
  through 
  cross-pollination. 
  

   Every 
  member 
  of 
  the 
  assemblage 
  propagates 
  it- 
  

   self, 
  and 
  is 
  onlv 
  checked 
  bv 
  its 
  own 
  greater 
  or 
  

  

  *.' 
  t/ 
  

  

  less 
  adaptation 
  to 
  the 
  given 
  conditions 
  of 
  life. 
  

   Bimpau 
  has 
  dealt 
  at 
  large 
  with 
  the 
  phenomenon 
  

   as 
  it 
  occurs 
  in 
  the 
  northern 
  and 
  middle 
  parts 
  of 
  

   Germany. 
  Even 
  Bivett's 
  " 
  Bearded 
  wheat,' 
  

   which 
  was 
  introduced 
  from 
  England 
  as 
  a 
  fine 
  

   improved 
  variety, 
  and 
  has 
  become 
  widely 
  dis- 
  

   tributed 
  throughout 
  Germany, 
  cannot, 
  keep 
  it- 
  

   self 
  pure. 
  It 
  is 
  found 
  mingled 
  almost 
  any- 
  

   where 
  with 
  the 
  old 
  local 
  varieties, 
  which 
  it 
  was 
  

   destined 
  to 
  supplant. 
  Any 
  lot 
  of 
  seed 
  ex- 
  

   hibits 
  such 
  impurities, 
  as 
  I 
  have 
  had 
  the 
  op- 
  

   portunity 
  of 
  observing 
  myself 
  in 
  sowings 
  in 
  

   the 
  experimental-garden. 
  But 
  the 
  impurities 
  

   are 
  only 
  mixtures, 
  and 
  all 
  the 
  plants 
  of 
  

   Rivett's 
  " 
  Bearded 
  wheat," 
  which 
  of 
  course 
  

   constitute 
  the 
  large 
  majority, 
  are 
  of 
  pure 
  blood. 
  

   This 
  may 
  be 
  confirmed 
  when 
  the 
  seeds 
  are 
  col- 
  

   lected 
  and 
  sown 
  separately 
  in 
  cultures 
  that 
  can 
  

   be 
  carefully 
  guarded. 
  

  

  