﻿330 
  BOTANICAL 
  GAZETTE. 
  ' 
  [ 
  December, 
  

  

  citing 
  Wallace 
  in 
  this 
  connection 
  — 
  it 
  may 
  not 
  be 
  due 
  to 
  the 
  

   intensity 
  of 
  the 
  light 
  and 
  heat. 
  

  

  On 
  the 
  other 
  hand 
  we 
  have 
  the 
  experiments 
  of 
  H. 
  C. 
  

   Sorby, 
  summarized 
  by 
  Vines 
  in 
  his 
  edition 
  of 
  Sach's 
  Text- 
  

   Book, 
  which 
  go 
  to 
  show 
  that 
  the 
  intensity 
  of 
  light 
  has 
  an 
  

   important 
  bearing 
  on 
  the 
  case. 
  According 
  to 
  Sorby, 
  "Ex- 
  

   posure 
  to 
  a 
  greater 
  or 
  less 
  degree 
  of 
  light 
  ma}^ 
  produce 
  a 
  

   great 
  quantitative 
  as 
  well 
  as 
  qualitative 
  difference 
  in 
  the 
  col- 
  

   oring 
  matters."^ 
  And 
  in 
  regard 
  to 
  the 
  experiments 
  of 
  Sachs, 
  

   that 
  flowers 
  developed 
  in 
  darkness 
  are 
  colored 
  in 
  much 
  the 
  

   same 
  way 
  as 
  those 
  developed 
  in 
  the 
  light, 
  Vines 
  remarks: 
  

   "Askenasy 
  has, 
  however, 
  found 
  that 
  this 
  is 
  by 
  no 
  means 
  al- 
  

   ways 
  the 
  case, 
  but 
  that 
  the 
  coloration 
  of 
  flowers 
  is 
  in 
  many 
  

   cases 
  much 
  modified 
  or 
  even 
  absent 
  when 
  the 
  plants 
  bearing 
  

   them 
  are 
  kept 
  in 
  darkness. 
  There 
  are 
  not 
  at 
  present 
  suffi- 
  

   cient 
  data 
  upon 
  which 
  to 
  base 
  an 
  explanation 
  of 
  the 
  diversity 
  

   of 
  behavior 
  of 
  flowers 
  in 
  this 
  respect, 
  but 
  it 
  appears 
  to 
  depend 
  

   upon 
  their 
  particular 
  hue. 
  Sorby 
  has 
  observed 
  that 
  the 
  red 
  

   coloring 
  matter 
  of 
  flowers 
  (which 
  is 
  probably 
  identical 
  with 
  

  

  erythrophyll) 
  is 
  formed 
  in 
  smaller 
  quantity 
  in 
  relativel}^^ 
  

   than 
  in 
  relatively 
  strong 
  lierht."^*^ 
  

  

  These 
  experiments 
  of 
  Askenasy, 
  and 
  to 
  some 
  extent 
  ot 
  

   Sachs 
  (here 
  taken 
  from 
  Hildebrand's 
  account 
  of 
  them), 
  were 
  

   to 
  the 
  effect 
  that 
  though 
  in 
  the 
  flowers 
  of 
  TuHpa 
  Gesneriana 
  

   (a 
  bulbous 
  plant), 
  the 
  red 
  color 
  of 
  the 
  cell 
  contents 
  is 
  formed 
  

   just 
  as 
  well 
  in 
  entire 
  darkness 
  as 
  in 
  the 
  light, 
  a 
  smaller 
  

   amount 
  of 
  it 
  was 
  made 
  in 
  the 
  flowers 
  of 
  Tropaeolum 
  majus, 
  

   Cheiranthus 
  Cheiri, 
  Phaseolus 
  multiflorus 
  and 
  Antirrhinum 
  

   majus. 
  And 
  according 
  to 
  Askenasy 
  almost 
  no 
  production 
  

   of 
  color 
  at 
  all 
  occurred 
  in 
  the 
  dark 
  in 
  the 
  flowers 
  of 
  Silene 
  

   pendula 
  ; 
  and 
  in 
  the 
  flow^ers 
  of 
  Orchis 
  ustulata 
  he 
  found 
  that 
  

   the 
  lower 
  lip 
  had 
  its 
  ordinary 
  color, 
  while 
  the 
  upper 
  hp 
  was 
  

   pure 
  white, 
  and 
  sometimes 
  the 
  entire 
  flowers. 
  Other 
  flowers 
  

   showed 
  a 
  paler 
  color 
  under 
  a 
  less 
  degree 
  of 
  light. 
  Hildebrano 
  

   also 
  mentions 
  w^iat 
  is 
  so 
  often 
  evident, 
  especially 
  in 
  the 
  case 
  

   of 
  fruits 
  exposed 
  to 
  the 
  sun, 
  that 
  the 
  red 
  color 
  is 
  forme" 
  

   more 
  on 
  one 
  side 
  than 
  on 
  the 
  other. 
  He 
  continues, 
  " 
  ^^l 
  

   hnd 
  that 
  many 
  plants 
  of 
  the 
  plain, 
  if 
  they 
  ascend 
  to 
  w^hei^ 
  

   hey 
  receive 
  a 
  brighter 
  illumination, 
  which 
  is 
  found 
  on 
  m?""' 
  

   tains, 
  are 
  colored 
  red, 
  as 
  for 
  example 
  AchilL^a 
  Millefo^ 
  

  

  8 
  

  

  _ 
  ^ 
  ^M 
  

  

  ch^J!.!?,' 
  "^^' 
  '' 
  necessary 
  for 
  the 
  discernment 
  of 
  colors, 
  the 
  celerity 
  with 
  which 
  » 
  

   oThVM 
  1^ 
  'r°"f 
  ''"''' 
  "^^^ 
  introduce 
  an 
  element 
  of 
  doubt, 
  that 
  what 
  is 
  sfif/^,o„ 
  

   of 
  liKht 
  may 
  have 
  been 
  effected 
  in 
  the 
  dark, 
  though 
  the 
  probabUities 
  are 
  that 
  the 
  co 
  

   were 
  so 
  produced. 
  

  

  «Text-BookofBotany,p. 
  767 
  

   1^ 
  Physiology 
  of 
  Plants, 
  p. 
  267. 
  

  

  