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  297 
  

  

  ment, 
  which 
  he 
  has 
  effected 
  with 
  his 
  varieties 
  of 
  

   peas. 
  I 
  have 
  repeated 
  it 
  with 
  the 
  sugar-corn, 
  

   which 
  gives 
  far 
  better 
  material 
  for 
  demonstra- 
  

   tion. 
  It 
  starts 
  from 
  the 
  inference 
  that 
  if 
  dissim- 
  

   ilarity 
  among 
  the 
  pollen 
  grains 
  is 
  excluded, 
  the 
  

   diversity 
  of 
  the 
  ovules 
  must 
  at 
  once 
  become 
  

   manifest 
  and 
  vice 
  versa. 
  In 
  other 
  terms, 
  if 
  a 
  

   hybrid 
  of 
  the 
  first 
  generation 
  is 
  not 
  allowed 
  to 
  

   fertilize 
  itself, 
  but 
  is 
  pollinated 
  by 
  one 
  of 
  its 
  

   parents, 
  the 
  result 
  will 
  be 
  in 
  accordance 
  with 
  the 
  

   Mendelian 
  formula. 
  

  

  In 
  order 
  to 
  see 
  an 
  effect 
  on 
  the 
  spikes 
  pro- 
  

   duced 
  in 
  this 
  way, 
  it 
  is 
  of 
  course 
  necessary 
  to 
  

   fertilize 
  them 
  with 
  the 
  pollen 
  of 
  the 
  variety, 
  

   and 
  not 
  with 
  that 
  of 
  the 
  specific 
  type. 
  The 
  

   latter 
  would 
  give 
  partly 
  pure 
  starchy 
  grains 
  

   and 
  partly 
  hybrid 
  kernels, 
  but 
  these 
  would 
  

   assume 
  the 
  same 
  type. 
  But 
  if 
  we 
  pollinate 
  the 
  

   hybrid 
  with 
  pollen 
  of 
  a 
  pure 
  sugar-corn, 
  we 
  

   may 
  predict 
  the 
  result 
  as 
  follows. 
  

  

  If 
  the 
  spike 
  of 
  the 
  hybrid 
  contains 
  dormant 
  

   paternal 
  marks 
  in 
  one-half 
  of 
  its 
  flowers 
  and 
  in 
  

   the 
  other 
  half 
  maternal 
  latent 
  qualities, 
  the 
  

   sugar-corn 
  pollen 
  will 
  combine 
  with 
  one-half 
  of 
  

   the 
  ovules 
  to 
  give 
  hybrids, 
  and 
  with 
  the 
  other 
  

   half 
  so 
  as 
  to 
  give 
  pure 
  sugar-grains. 
  Hence 
  

   we 
  see 
  that 
  it 
  will 
  be 
  possible 
  to 
  count 
  out 
  direct- 
  

   ly 
  the 
  two 
  groups 
  of 
  ovules 
  on 
  inspecting 
  the 
  

   ripe 
  and 
  dry 
  spikes. 
  Experience 
  teaches 
  us 
  

  

  