﻿676 
  Mutations 
  

  

  has 
  broad 
  elliptical 
  undivided 
  leaves. 
  On 
  

   the 
  middle 
  of 
  the 
  midvein 
  these 
  leaves 
  are 
  seen 
  

   to 
  bear 
  small 
  clusters 
  of 
  flowers; 
  indeed 
  this 
  

   is 
  the 
  only 
  place 
  where 
  flowers 
  are 
  produced. 
  

   Each 
  cluster 
  has 
  from 
  13 
  -- 
  15 
  flowers, 
  of 
  which 
  

   some 
  are 
  staminate 
  and 
  borne 
  on 
  stalks, 
  while 
  

   others 
  are 
  pistillate 
  and 
  nearly 
  sessile. 
  These 
  

   flowers 
  are 
  small 
  and 
  of 
  a 
  pale 
  greenish 
  color 
  

   and 
  yield 
  small 
  stone-fruits, 
  with 
  a 
  thin 
  

   coating 
  of 
  pulpy 
  tissue. 
  As 
  the 
  name 
  indicates, 
  

   this 
  mode 
  of 
  flowering 
  is 
  closely 
  similar 
  to 
  that 
  

   of 
  Ruscus, 
  which 
  however, 
  does 
  not 
  bear 
  its 
  

   flowers 
  and 
  berries 
  on 
  real 
  leaves, 
  but 
  on 
  leaf- 
  

   like 
  expansions 
  of 
  the 
  twigs. 
  Phyllonoma 
  rus- 
  

   cifolia, 
  a 
  saxifragaceous 
  plant, 
  bears 
  the 
  same 
  

   specific 
  name, 
  indicating 
  a 
  similar 
  origin 
  of 
  the 
  

   flowers. 
  Other 
  instances 
  have 
  been 
  collected 
  by 
  

   Casimir 
  de 
  Candolle, 
  but 
  their 
  number 
  is 
  very 
  

   small. 
  

  

  As 
  a 
  varietal 
  mark, 
  flowers 
  on 
  leaves 
  like- 
  

   wise 
  rarely 
  occur. 
  One 
  instance 
  however, 
  is 
  

   very 
  remarkable, 
  and 
  we 
  have 
  already 
  dealt 
  

   with 
  it, 
  when 
  treating 
  of 
  constant 
  varieties, 
  and 
  

   of 
  the 
  lack 
  of 
  vicinism 
  in 
  the 
  case 
  of 
  species 
  

   with 
  exclusive 
  self-fertilization. 
  

  

  It 
  is 
  the 
  " 
  Nepaul-barley 
  " 
  or 
  Hordeum 
  tri- 
  

   furcatum. 
  The 
  leaves, 
  which 
  in 
  this 
  case 
  bear 
  

   the 
  adventitious 
  flowers, 
  are 
  the 
  inner 
  scales 
  of 
  

   the 
  spikelets, 
  and 
  not 
  on 
  green 
  leaves 
  as 
  in 
  the 
  

  

  