﻿xvi 
  Contents 
  

  

  LECTURE 
  PAGE 
  

  

  XVII. 
  The 
  production 
  of 
  double 
  flowers 
  . 
  . 
  488 
  

   Sudden 
  appearance 
  of 
  double 
  flowers 
  in 
  

   horticulture. 
  Historical 
  evidence. 
  Ex- 
  

   perimental 
  origin 
  of 
  Chrysanthemum 
  

   segetum 
  plenum. 
  Dependency 
  upon 
  

   nourishment. 
  Petalody 
  of 
  stamens. 
  

  

  XVIII. 
  New 
  species 
  of 
  Oenothera 
  .... 
  516 
  

   Mutations 
  of 
  Oenothera 
  lamarckiana 
  in 
  

   the 
  wild 
  state 
  near 
  Hilversum. 
  New 
  

   varieties 
  of 
  O. 
  laevifolia, 
  O. 
  brevistylis, 
  

   and 
  0. 
  nanella. 
  New 
  elementary 
  species, 
  

   O. 
  gigas, 
  O. 
  rubrinervis, 
  albida, 
  and 
  ob- 
  

   longa. 
  O. 
  lata 
  a 
  pistillate 
  form. 
  In- 
  

   constancy 
  of 
  O. 
  scintillans. 
  

  

  XIX. 
  Experimental 
  pedigree-cultures 
  . 
  . 
  . 
  547 
  

   Pedigree 
  of 
  the 
  mutative 
  products 
  of 
  

   Oenothera 
  lamarckiana 
  in 
  the 
  Botan- 
  

   ical 
  Garden 
  at 
  Amsterdam. 
  Laws 
  of 
  

   mutability. 
  Sudden 
  and 
  repeated 
  leaps 
  

   from 
  an 
  unchanging 
  main 
  strain. 
  Con- 
  

   stancy 
  of 
  the 
  new 
  forms. 
  Mutations 
  in 
  

   all 
  directions. 
  

  

  XX. 
  Origin 
  of 
  wild 
  species 
  and 
  varieties 
  . 
  . 
  576 
  

   Problems 
  to 
  solve. 
  Capsella 
  heegeri. 
  

   Oenothera 
  biennis 
  cruciata. 
  Epilobium 
  

   hirsutum 
  cruciatum. 
  Hibiscus 
  Mos- 
  

   cheutos. 
  Purple 
  beech. 
  Monophyllous 
  

   strawberries. 
  Chances 
  of 
  success 
  with 
  

   new 
  mutations. 
  

  

  XXL 
  Mutations 
  in 
  horticulture 
  .... 
  604 
  

   Chelidonium 
  majus 
  lacinatum. 
  Dwarf 
  and 
  

   spineless 
  varieties. 
  Laciniate 
  leaves. 
  

   Monophyllous 
  and 
  broom-like 
  varieties. 
  

  

  