﻿682 
  Mutations 
  

  

  in 
  a 
  later 
  stage. 
  They 
  may 
  even 
  sometimes 
  be- 
  

   come 
  abnormal. 
  Stamens 
  may 
  unite 
  into 
  pairs, 
  

   or 
  carpels 
  bear 
  four 
  stigmas. 
  The 
  pollen-sacs 
  

   are 
  as 
  a 
  rule 
  barren, 
  the 
  mother-cells 
  under- 
  

   going 
  atrophy, 
  while 
  normal 
  grains 
  are 
  seen 
  but 
  

   rarely. 
  Likewise 
  the 
  ovaries 
  are 
  rudimentary, 
  

   but 
  Wittmack 
  has 
  observed 
  the 
  occasional 
  

   production 
  of 
  ripe 
  grains 
  from 
  these 
  abnormal 
  

   florets. 
  

  

  The 
  scale 
  is 
  seldom 
  seen 
  to 
  extend 
  any 
  far- 
  

   ther 
  upwards 
  than 
  the 
  supernumerary 
  flower. 
  

   But 
  in 
  the 
  rare 
  instances 
  where 
  it 
  does 
  pro- 
  

   long 
  its 
  growth, 
  it 
  may 
  repeat 
  the 
  abnormality 
  

   and 
  bear 
  a 
  second 
  floret 
  above 
  the 
  first. 
  This 
  of 
  

   course 
  is 
  generally 
  much 
  weaker, 
  and 
  more 
  rudi- 
  

   mentary. 
  

  

  Eaciborsky, 
  who 
  has 
  lately 
  given 
  a 
  full 
  and 
  

   very 
  accurate 
  description 
  of 
  this 
  anomaly, 
  lays 
  

   great 
  stress 
  upon 
  the 
  fact 
  that 
  it 
  is 
  quite 
  use- 
  

   less. 
  It 
  is 
  perhaps 
  the 
  most 
  obviously 
  useless 
  

   structure 
  in 
  the 
  whole 
  vegetable 
  kingdom. 
  Not- 
  

   withstanding 
  this, 
  it 
  has 
  come 
  to 
  be 
  as 
  complete- 
  

   ly 
  hereditary 
  as 
  any 
  of 
  the 
  most 
  beautiful 
  adap- 
  

   tations 
  in 
  nature. 
  Therefore 
  it 
  is 
  one 
  of 
  the 
  

   most 
  serious 
  objections 
  to 
  the 
  hypothesis 
  of 
  

   slow 
  and 
  gradual 
  improvements 
  on 
  the 
  sole 
  

   ground 
  of 
  their 
  usefulness. 
  The 
  struggle 
  for 
  

   life 
  and 
  natural 
  selection 
  are 
  manifestly 
  in- 
  

   adequate 
  to 
  give 
  even 
  the 
  slightest 
  indication 
  of 
  

  

  