﻿792 
  Fluctuations 
  

  

  uct 
  of 
  the 
  whole 
  field. 
  Rimpau, 
  who 
  has 
  made 
  

   a 
  thorough 
  study 
  of 
  this 
  evij 
  and 
  has 
  shown 
  its 
  

   dependency 
  on 
  various 
  external 
  conditions, 
  has 
  

   also 
  tried 
  to 
  find 
  methods 
  of 
  selection 
  with 
  the 
  

   aim 
  of 
  overcoming 
  it, 
  or 
  at 
  least 
  of 
  reducing 
  it 
  

   to 
  uninjurious 
  proportions. 
  But 
  in 
  these 
  ef- 
  

   forts 
  he 
  has 
  reached 
  no 
  practical 
  result. 
  The 
  

   annuals 
  are 
  simply 
  inexterminable. 
  

  

  Coming 
  to 
  the 
  alternative 
  side 
  of 
  the 
  problem 
  

   it 
  is 
  clear 
  that 
  annuals 
  have 
  always 
  been 
  ex- 
  

   cluded 
  in 
  the 
  selection. 
  Their 
  seeds 
  cannot 
  be 
  

   mixed 
  with 
  the 
  good 
  harvest, 
  not 
  even 
  accident- 
  

   ally, 
  since 
  they 
  have 
  ripened 
  in 
  a 
  previous 
  year. 
  

   In 
  order 
  to 
  bear 
  seeds 
  in 
  the 
  second 
  year 
  beets 
  

   must 
  be 
  taken 
  from 
  the 
  field, 
  and 
  kept 
  free 
  

   from 
  frost 
  through 
  the 
  winter. 
  The 
  following 
  

   spring 
  they 
  are 
  planted 
  out, 
  and 
  it 
  is 
  obvious 
  

   that 
  even 
  the 
  most 
  careless 
  farmer 
  is 
  not 
  liable 
  

   to 
  mix 
  them 
  with 
  annual 
  specimens. 
  Hence 
  we 
  

   may 
  conclude 
  that 
  a 
  strict 
  and 
  unexcelled 
  proc- 
  

   ess 
  of 
  selection 
  has 
  been 
  applied 
  to 
  the 
  destruc- 
  

   tion 
  of 
  this 
  tendency, 
  not 
  only 
  for 
  sugar-beets, 
  

   since 
  Vilmorin's 
  time, 
  when 
  selection 
  had 
  be- 
  

   come 
  a 
  well 
  understood 
  process, 
  but 
  also 
  for 
  

   forage-beets 
  since 
  the 
  beginning 
  of 
  beet- 
  

   culture. 
  Although 
  unconscious, 
  the 
  selection 
  of 
  

   biennials 
  must 
  have 
  been 
  uninterrupted 
  and 
  

   strict 
  throughout 
  many 
  centuries. 
  

  

  It 
  has 
  had 
  no 
  effect 
  at 
  all. 
  Annuals 
  are 
  seen 
  

  

  