﻿Unbalanced 
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  253 
  

  

  quirement 
  of 
  some 
  new 
  character. 
  The 
  deriva- 
  

   tive 
  species 
  has 
  one 
  unit 
  more 
  than 
  the 
  parent. 
  

   All 
  other 
  qualities 
  are 
  the 
  same 
  as 
  in 
  the 
  par- 
  

   ent. 
  Whenever 
  such 
  a 
  derivative 
  is 
  combined 
  

   with 
  its 
  parent 
  the 
  result 
  for 
  these 
  qualities 
  

   will 
  be 
  exactly 
  as 
  in 
  a 
  normal 
  fertilization. 
  In 
  

   such 
  ordinary 
  cases 
  it 
  is 
  obvious 
  that 
  each 
  char- 
  

   acter 
  of 
  the 
  pollen-parent 
  is 
  combined 
  with 
  the 
  

   same 
  character 
  of 
  the 
  pistil-parent. 
  There 
  may 
  

   be 
  slight 
  individual 
  differences, 
  but 
  each 
  unit- 
  

   character 
  will 
  become 
  opposed 
  to, 
  and 
  united 
  

   with, 
  the 
  same 
  unit-character 
  in 
  the 
  other 
  par- 
  

   ent. 
  In 
  the 
  offspring 
  the 
  units 
  will 
  thus 
  

   be 
  paired, 
  each 
  pair 
  consisting 
  of 
  two 
  equivalent 
  

   units. 
  As 
  to 
  their 
  character 
  the 
  units 
  of 
  each 
  

   single 
  pair 
  are 
  the 
  same, 
  only 
  they 
  may 
  exhibit 
  

   slight 
  differences 
  as 
  to 
  the 
  degree 
  of 
  develop- 
  

   ment 
  of 
  this 
  character. 
  

  

  Now 
  we 
  may 
  apply 
  this 
  conception 
  to 
  the 
  sex- 
  

   ual 
  combination 
  of 
  two 
  different 
  elementary 
  

   species, 
  assuming 
  one 
  to 
  be 
  the 
  derivative 
  of 
  

   the 
  other. 
  The 
  differentiating 
  mark 
  is 
  only 
  

   present 
  in 
  one 
  of 
  the 
  parents 
  and 
  wanting 
  in 
  the 
  

   other. 
  While 
  all 
  other 
  units 
  are 
  paired 
  in 
  the 
  

   hybrid, 
  this 
  one 
  is 
  not. 
  It 
  meets 
  with 
  no 
  mate, 
  

   and 
  must 
  therefore 
  remain 
  unpaired. 
  The 
  

   hybrid 
  of 
  two 
  such 
  elementary 
  species 
  is 
  in 
  

   some 
  way 
  incomplete 
  and 
  unnatural. 
  In 
  the 
  

   ordinary 
  course 
  of 
  things 
  all 
  individuals 
  derive 
  

  

  