﻿189°'] 
  * 
  BOTANICAL 
  GAZETTE. 
  

  

  329 
  

  

  the 
  exception 
  of 
  yellow, 
  which 
  was 
  constant 
  under 
  the 
  dif- 
  

   ferent 
  conditions 
  of 
  experimentation. 
  The 
  experiments 
  were 
  

   more 
  with 
  plants 
  in 
  the 
  contrasted 
  conditions 
  of 
  hght 
  and 
  

   darkness 
  than 
  in 
  different 
  degrees 
  of 
  intensity 
  of 
  light, 
  though 
  

   the 
  latter 
  was 
  also 
  considered. 
  Sachs 
  concluded 
  that 
  when 
  

   other 
  conditions 
  of 
  growth 
  are 
  normal, 
  light 
  has 
  httle 
  to 
  do 
  

  

  with 
  the 
  formation 
  of 
  the 
  colors 
  of 
  flowers. 
  He 
  says: 
  "As 
  

   long 
  as 
  sufficient 
  quantities 
  of 
  assimilated 
  materials 
  have 
  

   been 
  previously 
  accumulated, 
  or 
  are 
  produced 
  by 
  green 
  

   leaves 
  exposed 
  to 
  light, 
  flowers 
  are 
  developed 
  even 
  in 
  con- 
  

   tinuous 
  deep 
  darkness 
  which 
  are 
  of 
  normal 
  size, 
  form 
  and 
  

   color.* 
  Hildebrand 
  remarks 
  to 
  the 
  same 
  effect, 
  that 
  the 
  in- 
  

   nuence 
  of 
  Hght 
  is 
  intimately 
  associated 
  with 
  the 
  nourishment 
  

   the 
  flower 
  by 
  stored 
  up 
  food, 
  as 
  seen 
  in 
  the 
  case 
  of 
  bulbous 
  

   plants, 
  and 
  the 
  experiments 
  of 
  Askenasy 
  with 
  flowers 
  devel- 
  

   oped 
  on 
  branches 
  severed 
  from 
  the 
  parent 
  stock, 
  which 
  were 
  

   sometimes 
  of 
  normal 
  color. 
  " 
  From 
  these 
  few 
  examples," 
  

   ne 
  continues, 
  " 
  we 
  see 
  that 
  light 
  exerts 
  an 
  exceedingly 
  varied 
  

   jntluence 
  on 
  the 
  formation 
  of 
  the 
  blue 
  and 
  red 
  colors 
  in 
  dif- 
  

   jerent 
  plants, 
  but 
  whether 
  this 
  influence 
  would 
  be 
  shown 
  in 
  

   the 
  same 
  way 
  under 
  all 
  conditions 
  among 
  similar 
  plants 
  must 
  

   De 
  held 
  in 
  doubt. 
  "^ 
  His 
  final 
  conclusion 
  is 
  that 
  in 
  order 
  to 
  

   evelop 
  definite 
  colors 
  plants 
  are 
  inherently 
  disposed 
  to 
  re- 
  

   ceive 
  this 
  influence, 
  some 
  for 
  the 
  development 
  of 
  one 
  color, 
  

   lers 
  for 
  another; 
  some 
  plants 
  in 
  one 
  definite 
  direction, 
  

   others 
  in 
  another, 
  while 
  in 
  still 
  others 
  the 
  susceptibility 
  to 
  

   vaiy 
  may 
  lead 
  them 
  in 
  one 
  direction 
  as 
  well 
  as 
  another, 
  its 
  

   usetulness 
  to 
  the 
  plant 
  determining 
  what 
  line 
  of 
  color-varia- 
  

   "on 
  will 
  be 
  taken 
  and 
  ultimately 
  fixed. 
  « 
  

  

  DeLr 
  

  

  on 
  th 
  -^"^ 
  as 
  well 
  as 
  to 
  others 
  that 
  light 
  has 
  a 
  direct 
  inf 
  

  

  the 
  lormation 
  of 
  colors 
  in 
  plants 
  besides 
  the 
  green. 
  

  

  rl,r 
  *?^^^ 
  which 
  seem 
  to 
  disprove 
  this, 
  of 
  normal 
  colo 
  

  

  The 
  

  

  ors 
  pro- 
  

  

  1 
  . 
  — 
  "^ti^iL 
  accm 
  10 
  aisprove 
  mis, 
  01 
  uuiiuai 
  y^Kji^^i^ 
  t--- 
  

  

  thai 
  r 
  ? 
  ^^^^ness, 
  he 
  thinks 
  may 
  be 
  traced 
  to 
  other 
  causes 
  ; 
  

   th'il 
  ^^ 
  ^^^ 
  ^^ 
  present 
  the 
  moment 
  they 
  are 
  formed, 
  and 
  

   ^ 
  , 
  ^^Penments 
  to 
  prove 
  that 
  colors 
  mav 
  be 
  developed 
  in 
  

   shn 
  t!?^^ 
  should 
  not 
  be 
  confined 
  to 
  a 
  single 
  generation, 
  but 
  

   such 
  ^'^°^^ 
  ^^'"^^ 
  ^^^ey 
  are 
  capable 
  of 
  transmission.^ 
  Under 
  

   I 
  "^^"f^'tions 
  he 
  is 
  of 
  the 
  opinion 
  that 
  the 
  colors 
  would 
  at 
  

   fuln 
  ^^^^PPear. 
  He 
  agrees 
  with 
  the 
  idea 
  that 
  it 
  is 
  the 
  use- 
  

   !!!!i.^^_theplant 
  which 
  determines 
  their 
  colors, 
  although— 
  

  

  est- 
  Book 
  of 
  Botany, 
  p. 
  751. 
  Lehrbuch 
  der 
  Botanik, 
  p. 
  725. 
  

   'Col 
  ''l-°-P-52. 
  

  

  oration 
  etmatiSres 
  colorantes 
  des 
  plantes, 
  1. 
  c, 
  II, 
  152. 
  

  

  