﻿148 
  . 
  Harper: 
  Ixheritaxce 
  of 
  sugar 
  

  

  tendency 
  to 
  overlook 
  such 
  fluctuating 
  differences 
  in 
  the 
  interest 
  of 
  

   attempts 
  at 
  broad 
  generalizations. 
  

  

  I 
  have 
  endeavored 
  to 
  settle 
  the 
  points 
  here 
  involved 
  and 
  have 
  

   grown 
  a 
  number 
  of 
  such 
  intermediates 
  which 
  have 
  appeared 
  in 
  

   various 
  crosses 
  between 
  sweets, 
  and 
  flints, 
  dents 
  and 
  pops. 
  

  

  The 
  study 
  of 
  these 
  endosperm 
  characters 
  is 
  of 
  special 
  interest 
  

   since 
  the 
  endosperm 
  nuclei 
  in 
  general 
  are 
  the 
  product 
  of 
  a 
  triple 
  

   nuclear 
  fusion; 
  in 
  each 
  case 
  two 
  nuclei 
  from 
  the 
  mother 
  combine 
  

   with 
  one 
  from 
  the 
  male 
  parent. 
  The 
  effect 
  of 
  this 
  unequal 
  repre- 
  

   sentation 
  of 
  the 
  two 
  parents 
  in 
  the 
  endosperm 
  can 
  be 
  checked 
  up 
  

   by 
  comparison 
  with 
  the 
  expression 
  of 
  the 
  same 
  characters 
  as 
  trans- 
  

   mitted 
  to 
  the 
  next 
  generation 
  through 
  the 
  embryo 
  which 
  arises 
  

   from 
  the 
  normally 
  fertilized 
  egg. 
  The 
  morphological 
  nature 
  

   and 
  phylogenetic 
  origin 
  of 
  the 
  triple 
  fusion 
  in 
  forming 
  the 
  pri- 
  

   mary 
  endosperm 
  nucleus 
  have 
  not 
  been 
  as 
  yet 
  worked 
  out, 
  but 
  

   functionally 
  and 
  from 
  the 
  genetic 
  standpoint 
  it 
  is 
  a 
  triploid 
  

   growth 
  which 
  is 
  crowded 
  out 
  and 
  absorbed 
  by 
  the 
  normal 
  embryo. 
  

   The 
  study 
  of 
  reciprocal 
  crosses 
  with 
  reference 
  to 
  the 
  expression 
  

   of 
  these 
  endosperm 
  characters 
  afford 
  ideal 
  conditions 
  for 
  deter- 
  

   mining 
  the 
  effects 
  of 
  a 
  double 
  as 
  contrasted 
  with 
  a 
  single 
  set 
  of 
  

   chromosomes 
  from 
  the 
  same 
  parent, 
  so-called 
  dosage 
  phenomena, 
  

   etc. 
  I 
  shall 
  not 
  take 
  up 
  these 
  questions 
  In 
  the 
  present 
  paper 
  since 
  

   I 
  desire 
  first 
  to 
  establish 
  and 
  clear 
  up 
  the 
  facts 
  as 
  to 
  the 
  occurrence 
  

   of 
  intermediates 
  between 
  starch 
  and 
  sugar 
  corns 
  and 
  the 
  behavior 
  

   of 
  these 
  intermediates 
  when 
  grown 
  and 
  selfed. 
  

  

  The 
  interesting 
  paper 
  by 
  Weatherwax 
  ('19) 
  establishes 
  the 
  

   fact 
  that 
  the 
  embry^o 
  sac 
  In 
  corn 
  Is 
  formed 
  after 
  the 
  manner 
  of 
  the 
  

   dicotyledonous 
  rather 
  than 
  the 
  lily 
  type 
  so 
  that 
  there 
  is 
  no 
  possi- 
  

   bility 
  that 
  either 
  of 
  the 
  polar 
  nuclei 
  which 
  fuse 
  In 
  the 
  endosperm 
  

   nucleus 
  or 
  their 
  parents 
  were 
  formed 
  by 
  a 
  reduction 
  division 
  and 
  

   the 
  possible 
  complications 
  as 
  to 
  the 
  so-called 
  genetic 
  constitution 
  

   of 
  the 
  nuclei 
  of 
  an 
  endosperm 
  of 
  the 
  lily 
  type 
  are 
  not 
  present 
  in 
  

  

  corn. 
  

  

  I 
  have 
  worked 
  with 
  the 
  following 
  races: 
  

   Four 
  flints: 
  Canadian 
  Early 
  Yellow, 
  Longfellow, 
  Long 
  White 
  

  

  Flint, 
  and 
  Hall's 
  Golden 
  Nugget. 
  

   Eight 
  dent 
  corns: 
  Wisconsin 
  White 
  Dent, 
  Silver 
  King, 
  Bloody 
  

  

  Butcher, 
  Gaunt's 
  Golden 
  Dent, 
  Long's 
  Champion 
  Dent, 
  King 
  

  

  Philip 
  Red 
  Cob, 
  Eureka 
  Dent. 
  

  

  