﻿138 
  INTRODUCTION 
  TO 
  BOTANY 
  

  

  light, 
  dust-like 
  pollen, 
  while 
  others 
  have 
  pollen 
  which 
  coheres 
  

   in 
  sticky 
  masses 
  -- 
  and 
  so 
  on, 
  with 
  a 
  multitude 
  of 
  other 
  differ- 
  

   ences. 
  These 
  singular 
  facts 
  were 
  first 
  explained 
  in 
  part 
  by 
  two 
  

   eighteenth-century 
  German 
  botanists, 
  Kolretiter 
  and 
  Sprengel, 
  

   working 
  independently 
  of 
  each 
  other. 
  Little 
  was 
  afterwards 
  

   done 
  to 
  clear 
  up 
  the 
  subject 
  until 
  Charles 
  Darwin 
  and 
  a 
  host 
  

   of 
  other 
  investigators, 
  beginning 
  soon 
  after 
  the 
  middle 
  of 
  the 
  

   nineteenth 
  century, 
  worked 
  out 
  the 
  details 
  of 
  the 
  methods 
  

   of 
  pollination. 
  1 
  

  

  As 
  a 
  result 
  of 
  these 
  studies 
  it 
  may 
  be 
  said 
  that 
  floicers 
  owe 
  

   most 
  of 
  their 
  structural 
  and 
  other 
  characteristics 
  to 
  the 
  fact 
  that 
  

   these 
  things 
  have 
  enabled 
  them 
  to 
  secure 
  the 
  needed 
  pollination. 
  

  

  130. 
  Classification 
  according 
  to 
  means 
  of 
  pollination. 
  It 
  is 
  

   impossible 
  in 
  any 
  brief 
  way 
  to 
  give 
  much 
  of 
  an 
  account 
  of 
  the 
  

   groups 
  into 
  which 
  flowers 
  are 
  divided 
  with 
  reference 
  to 
  their 
  

  

  means 
  of 
  securing 
  pollination. 
  Before 
  out- 
  

   lining 
  these 
  groups 
  it 
  is 
  necessary 
  to 
  define 
  

   the 
  word 
  nectar. 
  This 
  name 
  is 
  given 
  to 
  the 
  

   sweet 
  liquid 
  found 
  in 
  many 
  flowers 
  --for 
  

   example, 
  columbine, 
  honeysuckle, 
  and 
  red 
  

   clover. 
  The 
  nectar 
  is 
  secreted 
  by 
  special 
  

   organs 
  known 
  as 
  net-fur 
  <//>/>i<ls 
  (iigs. 
  120 
  

   FIG. 
  120. 
  Flower 
  of 
  and 
  129) 
  and 
  is 
  often 
  stored 
  at 
  the 
  base 
  of 
  

  

  grape, 
  with 
  nectar 
  ,-, 
  , 
  -\-:,i 
  i 
  

  

  glami 
  S 
  (n)auhebase 
  lllr 
  corolla 
  ' 
  sometimes 
  in 
  little 
  pouches, 
  as 
  

   of 
  the 
  ovary 
  ^ 
  the 
  columbines 
  and 
  the 
  honeysuckles. 
  

  

  Some 
  of 
  the 
  most 
  important 
  groups 
  of 
  

   flowers, 
  classified 
  according 
  to 
  their 
  qualifications 
  for 
  securing 
  

   pollination, 
  are 
  the 
  following: 
  

  

  1. 
  Flowers 
  mostly 
  with 
  inconspicuous 
  perianth, 
  and 
  usually 
  

   without 
  nectar, 
  destitute 
  of 
  odor, 
  generally 
  with 
  moist 
  or 
  

   sticky 
  pollen, 
  with 
  knob-like 
  or 
  club-shaped 
  stigmas. 
  

  

  2. 
  Flowers 
  with 
  inconspicuous 
  perianth, 
  destitute 
  of 
  odor, 
  

   without 
  nectar, 
  with 
  dust-like 
  pollen, 
  with 
  feathery 
  stigmas 
  

   (fig. 
  121). 
  

  

  1 
  See 
  Knuth-Davis, 
  Handbook 
  of 
  Flower 
  Pollination, 
  Vol. 
  I. 
  Clarendon 
  

   Press, 
  Oxford. 
  

  

  