﻿Multiplication 
  of 
  Extremes 
  759 
  

  

  ordinarily 
  difficult, 
  if 
  not 
  impossible, 
  to 
  discern 
  

   the 
  part 
  which 
  each 
  of 
  the 
  three 
  great 
  branches 
  

   of 
  variability 
  has 
  taken 
  in 
  the 
  origination 
  of 
  the 
  

   product. 
  A 
  full 
  analysis 
  is 
  rarely 
  possible, 
  and 
  

   the 
  treatment 
  of 
  one 
  of 
  the 
  three 
  factors 
  must 
  

   necessarily 
  remain 
  incomplete. 
  

  

  Notwithstanding 
  these 
  considerations, 
  I 
  will 
  

   now 
  give 
  some 
  examples 
  in 
  order 
  to 
  show 
  that 
  

   fluctuating 
  variability 
  plays 
  a 
  prominent 
  part 
  in 
  

   these 
  improvements. 
  Of 
  course 
  it 
  is 
  the 
  third 
  

   in 
  importance 
  in 
  the 
  series. 
  First 
  comes 
  the 
  

   choice 
  of 
  the 
  material 
  from 
  the 
  assemblage 
  of 
  

   species, 
  elementary 
  species 
  and 
  varieties. 
  

   Hybridization 
  comes 
  next 
  in 
  importance. 
  But 
  

   even 
  the 
  hybrids 
  of 
  the 
  best 
  parents 
  may 
  be 
  im- 
  

   proved, 
  because 
  they 
  are 
  no 
  less 
  subject 
  to 
  

   Quetelet's 
  law 
  than 
  any 
  other 
  strain. 
  Any 
  

   large 
  number 
  of 
  hybrids 
  of 
  the 
  same 
  ancestry 
  

   will 
  prove 
  this, 
  and 
  often 
  the 
  excellency 
  of 
  a 
  

   hybrid 
  variety 
  depends 
  chiefly, 
  or 
  at 
  least 
  defi- 
  

   nitely, 
  on 
  the 
  selection 
  of 
  the 
  best 
  individuals. 
  

   Being 
  propagated 
  only 
  in 
  a 
  vegetative 
  way, 
  they 
  

   retain 
  their 
  original 
  good 
  qualities 
  through 
  all 
  

   further 
  culture 
  and 
  multiplication. 
  

  

  As 
  an 
  illustrative 
  example 
  I 
  will 
  take 
  the 
  

   genus 
  Canna. 
  Originally 
  cultivated 
  for 
  its 
  

   large 
  and 
  bright 
  foliage 
  only, 
  it 
  has 
  since 
  be- 
  

   come 
  a 
  flowering 
  plant 
  of 
  value. 
  Our 
  garden 
  

   strains 
  have 
  originated 
  by 
  the 
  crossing 
  of 
  

  

  