﻿Multiplication 
  of 
  Extremes 
  749 
  

  

  life. 
  Afterwards 
  only 
  the 
  minor 
  points 
  remain 
  

   to 
  be 
  regulated. 
  This 
  makes 
  it 
  at 
  once 
  clear 
  

   that 
  the 
  range 
  of 
  individual 
  and 
  partial 
  vari- 
  

   ability 
  together 
  must 
  be 
  wider 
  than 
  that 
  of 
  

   either 
  of 
  them, 
  taken 
  alone. 
  Partial 
  fluctua- 
  

   tions 
  cannot, 
  of 
  course, 
  be 
  excluded. 
  Thus 
  our 
  

   comparison 
  is 
  limited 
  to 
  individual 
  and 
  partial 
  

   variability 
  on 
  one 
  side, 
  and 
  partial 
  fluctuations 
  

   alone 
  on 
  the 
  other 
  side. 
  

  

  Intra-specific 
  selection 
  is 
  thus 
  seen 
  to 
  fall 
  

   under 
  two 
  heads: 
  a 
  selection 
  between 
  the 
  in- 
  

   dividuals, 
  and 
  a, 
  choice 
  within 
  each 
  of 
  them. 
  

   The 
  first 
  affords 
  a 
  wider 
  and 
  the 
  latter 
  a 
  nar- 
  

   rower 
  field. 
  

  

  Individual 
  variability, 
  considered 
  as 
  the 
  re- 
  

   sult 
  of 
  outward 
  influences 
  operative 
  during 
  ex- 
  

   treme 
  youth, 
  can 
  be 
  excluded 
  in 
  a 
  very 
  simple 
  

   manner. 
  Obviously 
  it 
  suffices 
  to 
  exclude 
  ex- 
  

   treme 
  youth, 
  in 
  other 
  words, 
  to 
  exclude 
  the 
  use 
  

   of 
  seeds. 
  Multiplication 
  in 
  a 
  vegetative 
  way, 
  

   by 
  grafting 
  and 
  budding, 
  by 
  runners 
  or 
  roots, 
  

   or 
  by 
  simple 
  division 
  of 
  rootstocks 
  and 
  bulbs 
  is 
  

   the 
  way 
  in 
  which 
  to 
  limit 
  variability 
  to 
  the 
  par- 
  

   tial 
  half. 
  This 
  is 
  all 
  we 
  may 
  hope 
  to 
  attain, 
  but 
  

   experience 
  shows 
  that 
  it 
  is 
  a 
  very 
  efficient 
  means 
  

   of 
  limitation. 
  Partial 
  fluctuations 
  are 
  gener- 
  

   ally 
  far 
  smaller 
  than 
  individual 
  and 
  partial 
  

   fluctuations 
  together. 
  

  

  Individual 
  variability 
  in 
  the 
  vegetable 
  king- 
  

  

  