﻿174 
  Retrograde 
  Varieties 
  

  

  ing 
  flowers 
  with 
  a 
  uniform 
  perianth 
  and 
  six 
  

   stamens, 
  recalling 
  thereby 
  the 
  supposed 
  ances- 
  

   tral 
  type. 
  The 
  way 
  in 
  which 
  he 
  got 
  these 
  was 
  

   as 
  follows: 
  he 
  started 
  from 
  some 
  slight 
  devia- 
  

   tions 
  observed 
  in 
  the 
  flowers 
  of 
  the 
  pale 
  spe- 
  

   cies, 
  sowed 
  the 
  seeds 
  in 
  large 
  numbers 
  and 
  se- 
  

   lected 
  from 
  the 
  seedlings 
  only 
  those, 
  which 
  

   clearly 
  showed 
  anomalies 
  in 
  the 
  expected 
  

   atavistic 
  direction. 
  By 
  repeating 
  this 
  during 
  

   several 
  generations 
  he 
  at 
  last 
  reached 
  his 
  goal 
  

   and 
  was 
  able 
  to 
  give 
  reality 
  to 
  the 
  prototype, 
  

   which 
  formerly 
  was 
  only 
  a 
  hypothetical 
  one. 
  

   The 
  Iris 
  kaempferi, 
  a 
  large-flowered 
  Japanese 
  

   species 
  much 
  cultivated 
  in 
  gardens, 
  is 
  very 
  vari- 
  

   able 
  in 
  the 
  number 
  of 
  the 
  different 
  parts 
  of 
  its 
  

   flowers, 
  and 
  may 
  in 
  some 
  instances 
  be 
  seen 
  even 
  

   with 
  six 
  stamens. 
  If 
  studied 
  in 
  the 
  same 
  way 
  as 
  

   Heinricher's 
  iris, 
  it 
  no 
  doubt 
  will 
  yield 
  highly 
  

   interesting 
  and 
  confirmatory 
  results. 
  

  

  Many 
  other 
  instances 
  of 
  such 
  systematic 
  atav- 
  

   ism 
  could 
  be 
  given, 
  and 
  every 
  botanist 
  can 
  easily 
  

   add 
  some 
  from 
  memory. 
  Many 
  anomalies, 
  oc- 
  

   curring 
  spontaneously, 
  are 
  evidently 
  due 
  to 
  the 
  

   same 
  principle, 
  but 
  it 
  would 
  take 
  too 
  long 
  to 
  

   describe 
  them. 
  

  

  Reversion 
  may 
  occur 
  either 
  by 
  buds 
  or 
  by 
  

   seeds. 
  It 
  is 
  highly 
  probable 
  that 
  it 
  occurs 
  more 
  

   readily 
  by 
  sexual 
  than 
  by 
  asexual 
  propagation. 
  

   But 
  if 
  we 
  restrict 
  the 
  discussion 
  to 
  the 
  limits 
  

  

  