﻿556 
  Mutations 
  

  

  thrown 
  away 
  as 
  soon 
  as 
  they 
  showed 
  their 
  dif- 
  

   ferentiating 
  characters 
  in 
  order 
  to 
  make 
  room 
  

   for 
  the 
  remaining 
  ones. 
  At 
  last 
  only 
  a 
  few 
  

   plants 
  were 
  left 
  to 
  blossom 
  in 
  order 
  to 
  perpet- 
  

   uate 
  the 
  race. 
  I 
  have 
  indicated 
  for 
  each 
  genera- 
  

   tion 
  the 
  number 
  of 
  mutants 
  of 
  each 
  of 
  the 
  ob- 
  

   served 
  forms, 
  placing 
  them 
  in 
  vertical 
  columns 
  

   underneath 
  their 
  respective 
  heads. 
  The 
  three 
  

   first 
  generations 
  were 
  biennial, 
  but 
  the 
  five 
  last 
  

   annual. 
  

  

  PEDIGREE 
  OF 
  A 
  MUTATING 
  FAMILY 
  OF 
  OENOTHERA 
  LAMARCKIANA 
  

   IN 
  THE 
  EXPERIMENTAL 
  GARDEN 
  AT 
  AMSTERDAM. 
  

  

  Gener: 
  O.gig. 
  albida 
  obi. 
  rubrin. 
  Lam. 
  nanella 
  lata. 
  scint. 
  

  

  VIII. 
  

  

  VII. 
  

  

  VI. 
  

  

  V. 
  

  

  IV. 
  1 
  

  

  III. 
  

   II. 
  

  

  I. 
  

  

  It 
  is 
  most 
  striking 
  that 
  the 
  various 
  mutations 
  

   of 
  the 
  evening-primrose 
  display 
  a 
  great 
  degree 
  

   of 
  regularity. 
  There 
  is 
  no 
  chaos 
  of 
  forms, 
  no 
  

   indefinite 
  varying 
  in 
  all 
  degrees 
  and 
  in 
  all 
  direc- 
  

   tions. 
  Quite 
  on 
  the 
  contrary, 
  it 
  is 
  at 
  once 
  evi- 
  

   dent 
  that 
  very 
  simple 
  rules 
  govern 
  the 
  whole 
  

   phenomenon. 
  

  

  I 
  shall 
  now 
  attempt 
  to 
  deduce 
  these 
  laws 
  from 
  

  

  