﻿A 
  misconception 
  as 
  to 
  the 
  structure 
  of 
  the 
  ear 
  of 
  maize 
  

  

  Paul 
  Weatherwax 
  

   (with 
  six 
  text 
  figures) 
  

  

  It 
  IS 
  a 
  fact 
  of 
  common 
  knowledge 
  and 
  general 
  interest 
  that 
  the 
  

  

  gularly 
  

  

  By 
  the 
  

  

  layman 
  this 
  has 
  usually 
  been 
  regarded 
  as 
  one 
  of 
  Nature's 
  curiosi- 
  

   ties, 
  not 
  necessarily 
  to 
  be 
  explained 
  in 
  any 
  way; 
  but 
  the 
  botanist 
  

   long 
  ago 
  found 
  it 
  to 
  be 
  the 
  expression 
  of 
  a 
  morphological 
  qhar- 
  

   acteristic 
  of 
  the 
  whole 
  tribe 
  (Maydeae) 
  to 
  which 
  maize 
  belongs. 
  

  

  Ordinarily 
  the 
  spikelets 
  in 
  all 
  parts 
  of 
  both 
  inflorescences 
  of 
  

   the 
  maize 
  plant 
  are 
  borne 
  in 
  pairs, 
  one 
  sessile 
  and 
  the 
  other 
  pedi- 
  

   celled. 
  The 
  fundamental 
  structural 
  unit 
  of 
  the 
  ear 
  of 
  corn 
  is 
  a 
  

   row 
  of 
  these 
  paired 
  spikelets, 
  or, 
  in 
  other 
  words, 
  a 
  pair 
  of 
  rows 
  of 
  

   grains, 
  each 
  spikelet 
  producing 
  one 
  grain. 
  As 
  a 
  rule 
  there 
  is 
  no 
  

   ascertainable 
  difference 
  between 
  the 
  two 
  grains 
  produced 
  in 
  a 
  

   pair 
  of 
  spikelets, 
  but 
  there 
  is 
  abundant 
  evidence 
  that 
  the 
  sessile 
  

   spikelets 
  are 
  responsible 
  for 
  one 
  row 
  and 
  the 
  pedicelled 
  ones 
  for 
  

   the 
  other. 
  

  

  It 
  often 
  happens 
  that 
  an 
  ear 
  h'as 
  more 
  rows 
  at 
  the 
  base 
  than 
  

   at 
  the 
  tip, 
  the 
  difference 
  in 
  number 
  being 
  always 
  two 
  or 
  a 
  multiple 
  

   of 
  two. 
  When 
  the 
  difference 
  in 
  number 
  is 
  two, 
  both 
  rows 
  are 
  

   dropped 
  at 
  exactly 
  the 
  same 
  distance 
  from 
  the 
  base 
  of 
  the 
  ear; 
  

   if 
  the 
  difference 
  is 
  more 
  than 
  two, 
  two 
  rows 
  may 
  be 
  dropped 
  at 
  

   one 
  distance 
  from 
  the 
  end 
  of 
  the 
  ear, 
  two 
  at 
  another, 
  and 
  so 
  on. 
  

   Thus, 
  no 
  part 
  of 
  the 
  ear 
  is 
  ever 
  left 
  with 
  an 
  odd 
  number 
  of 
  rows. 
  

  

  The 
  natural 
  inference 
  has 
  been 
  that 
  these 
  irregularities 
  are 
  

   due 
  to 
  the 
  discontinuance 
  of 
  one 
  or 
  more 
  rows 
  of 
  paired 
  spikelets, 
  

   an 
  explanation 
  apparently 
  in 
  harmony 
  with 
  most 
  facts 
  and 
  theories 
  

   centered 
  in 
  this 
  unique 
  structure. 
  It 
  is 
  somewhat 
  surprising, 
  

   therefore, 
  to 
  find 
  in 
  connection 
  with 
  a 
  recent 
  theory* 
  as 
  to 
  the 
  

   origin 
  of 
  the 
  ear 
  of 
  maize, 
  a 
  new 
  explanation 
  of 
  this 
  irregularity 
  

   in 
  the 
  rows. 
  

  

  * 
  Collins, 
  G. 
  N. 
  Structure 
  of 
  the 
  maize 
  ear 
  as 
  indicated 
  in 
  Zea-Euchlaena 
  hy- 
  

   brids. 
  Jour. 
  Agr. 
  Research 
  17: 
  127-135. 
  pL 
  16-18 
  + 
  f, 
  i. 
  1919. 
  

  

  359 
  

  

  