﻿Production 
  of 
  Double 
  Flowers 
  513 
  

  

  This 
  is 
  proven 
  in 
  the 
  simplest 
  way 
  by 
  the 
  re- 
  

   sult 
  of 
  our 
  own 
  experiment. 
  

  

  In 
  the 
  double 
  field-marigold 
  we 
  have 
  the 
  very 
  

   first 
  generation 
  of 
  a 
  variety 
  of 
  pure 
  and 
  not 
  

   hybrid 
  origin. 
  It 
  shows 
  the 
  new 
  attribute 
  in 
  

   its 
  full 
  development. 
  It 
  has 
  flower-heads 
  near- 
  

   ly 
  as 
  completely 
  filled 
  as 
  the 
  best 
  double 
  varie- 
  

   ties 
  of 
  allied 
  cultivated 
  composites. 
  In 
  the 
  sec- 
  

   ond 
  generation 
  it 
  reached 
  heads 
  with 
  200 
  rays 
  

   each, 
  and 
  much 
  larger 
  numbers 
  will 
  seldom 
  be 
  

   seen 
  in 
  older 
  species 
  on 
  heads 
  of 
  equal 
  size. 
  I 
  

   have 
  compared 
  my 
  novelty 
  with 
  the 
  choicest 
  

   double 
  camomiles 
  and 
  others, 
  but 
  failed 
  to 
  dis- 
  

   cover 
  any 
  real 
  difference. 
  Improvement 
  of 
  the 
  

   variety 
  developed 
  in 
  the 
  experiments 
  carried 
  on 
  

   by 
  myself 
  seems 
  to 
  be 
  excluded 
  by 
  the 
  fact 
  

   that 
  it 
  comes 
  into 
  conflict 
  with 
  the 
  same 
  difficul- 
  

   ty 
  that 
  confronts 
  the 
  older 
  cultivated 
  species, 
  

   viz. 
  : 
  the 
  increasing 
  sterility 
  of 
  the 
  race. 
  

  

  It 
  is 
  perfectly 
  evident 
  that 
  this 
  double 
  mari- 
  

   gold 
  is 
  now 
  quite 
  constant. 
  Continuously 
  va- 
  

   rying 
  about 
  a 
  fixed 
  average 
  it 
  may 
  live 
  through 
  

   centuries, 
  but 
  the 
  mean 
  and 
  the 
  limits 
  will 
  al- 
  

   ways 
  remain 
  the 
  same, 
  as 
  in 
  the 
  case 
  of 
  the 
  

   ever-sporting 
  varieties. 
  

  

  Throughout 
  this 
  lecture 
  I 
  have 
  spoken 
  of 
  

   double 
  flowers 
  and 
  double 
  flower-heads 
  of 
  com- 
  

   posites 
  as 
  of 
  one 
  single 
  group. 
  They 
  are 
  as 
  

   nearly 
  related 
  from 
  the 
  hereditary 
  point 
  of 
  

  

  