﻿776 
  Fluctuations 
  

  

  2 
  and 
  the 
  regression 
  3. 
  In 
  other 
  words 
  the 
  av- 
  

   erage 
  of 
  the 
  progeny 
  has 
  gained 
  over 
  the 
  aver- 
  

   age 
  of 
  the 
  original 
  variety 
  slightly 
  more 
  than 
  

   one-third, 
  and 
  slightly 
  less 
  than 
  one-half 
  of 
  the 
  

   parental 
  deviation. 
  I 
  have 
  repeated 
  this 
  exper- 
  

   iment 
  of 
  Fritz 
  Miiller 
  's 
  and 
  obtained 
  nearly 
  the 
  

   same 
  regression 
  of 
  three-fifths, 
  though 
  working 
  

   with 
  another 
  variety, 
  and 
  under 
  widely 
  different 
  

   climatic 
  conditions. 
  

  

  The 
  figures 
  of 
  Fritz 
  Miiller 
  were, 
  as 
  given 
  be- 
  

   low, 
  in 
  one 
  experiment. 
  In 
  the 
  last 
  column 
  I 
  

   put 
  the 
  improvement 
  calculated 
  for 
  a 
  propor- 
  

   tion 
  of 
  two-fifths 
  above 
  the 
  initial 
  average 
  of 
  12. 
  

  

  Rows 
  on 
  Average 
  of 
  rows 
  12 
  + 
  % 
  of 
  

  

  parent 
  ears 
  of 
  progeny 
  Difference 
  

  

  14 
  12.6 
  12.8 
  

  

  16 
  14.1 
  13.6 
  

  

  18 
  15.2 
  14.4 
  

  

  20 
  15.8 
  15.2 
  

  

  22 
  16.1 
  16.0 
  

  

  Gralton, 
  in 
  his 
  work 
  on 
  natural 
  inheritance, 
  

   describes 
  an 
  experiment 
  with 
  the 
  seeds 
  of 
  the 
  

   sweet 
  pea 
  or 
  Lafhyrus 
  odoratus. 
  He 
  deter- 
  

   mined 
  the 
  average 
  size 
  in 
  a 
  lot 
  of 
  purchased 
  

   seeds, 
  and 
  selected 
  groups 
  of 
  seeds 
  of 
  differ- 
  

   ent, 
  but 
  for 
  each 
  group 
  constant, 
  sizes. 
  These 
  

   were 
  sown, 
  and 
  the 
  average 
  of 
  the 
  seeds 
  was 
  

   determined 
  anew 
  in 
  the 
  subsequent 
  harvest 
  they 
  

   yielded. 
  These 
  figures 
  agreed 
  with 
  the 
  rule 
  of 
  

   Vilmorin 
  and 
  were 
  calculated 
  in 
  the 
  manner 
  

  

  