﻿POLLINATION 
  AND 
  FERTILIZATION 
  

  

  149 
  

  

  found 
  a 
  body 
  shaped 
  somewhat 
  like 
  a 
  grain 
  of 
  wheat 
  (fig. 
  134, 
  

   C 
  and 
  D). 
  This 
  body, 
  the 
  corpusculum, 
  is 
  attached 
  at 
  each 
  

   side 
  to 
  one 
  pollen 
  mass 
  of 
  each 
  of 
  the 
  two 
  adjacent 
  anthers 
  

   (fig. 
  134, 
  B 
  and 
  C*). 
  Along 
  the 
  corpusculum 
  runs 
  a 
  slit 
  which 
  

   gradually 
  narrows 
  toward 
  the 
  upper 
  end 
  and 
  thus 
  acts 
  as 
  a 
  

   clip, 
  holding 
  firmly 
  any 
  small 
  object 
  that 
  is 
  drawn 
  into 
  it. 
  As 
  

   the 
  exterior 
  of 
  the 
  flower 
  is 
  smooth 
  and 
  slippery, 
  the 
  only 
  way 
  

   in 
  which 
  an 
  insect 
  can 
  hold 
  itself 
  in 
  place 
  upon 
  it 
  is 
  by 
  insert- 
  

   ing 
  its 
  claws 
  in 
  the 
  slit 
  of 
  a 
  corpusculum. 
  When 
  the 
  insect 
  

  

  corp 
  

  

  C 
  

  

  D 
  

  

  Fiu. 
  134. 
  Flower 
  of 
  the 
  milkweed 
  

  

  A, 
  general 
  view 
  ; 
  B, 
  side 
  view 
  of 
  flower 
  after 
  removal 
  of 
  the 
  sepals, 
  petals, 
  and 
  

   nectar-bearing 
  organs 
  ; 
  C, 
  pollen 
  masses 
  with 
  attached 
  clip 
  ; 
  D, 
  pollen 
  masses 
  

   with 
  clip 
  attached 
  to 
  foot 
  of 
  a 
  bee; 
  cal, 
  calyx; 
  co, 
  corolla 
  ; 
  c/i, 
  stigmatic 
  cham- 
  

   ber, 
  inside 
  of 
  which 
  is 
  the 
  stigma 
  ; 
  curp, 
  corjntxculum, 
  or 
  body 
  to 
  which 
  the 
  

   pollen 
  masses 
  are 
  attached, 
  acting 
  as 
  a 
  clip; 
  loc, 
  locule, 
  or 
  pollen 
  chamber 
  of 
  

   anther; 
  po, 
  pollen 
  mass. 
  All 
  somewhat 
  enlarged. 
  A 
  and 
  C, 
  after 
  Prautl; 
  B, 
  

   after 
  Herman 
  Miiller 
  ; 
  D, 
  after 
  Keruer 
  

  

  attempts 
  to 
  fly 
  away, 
  it 
  drags 
  the 
  corpusculum 
  and 
  attached 
  

   pollen 
  masses 
  with 
  it, 
  suspended 
  by 
  one 
  or 
  more 
  claws 
  

   (fig. 
  134, 
  D), 
  or 
  sometimes 
  it 
  is 
  held 
  fast 
  and 
  dies. 
  Hairy 
  

   insects, 
  like 
  bumblebees, 
  often 
  carry 
  away 
  many 
  pollen 
  masses 
  

   on 
  the 
  hairs 
  of 
  the 
  under 
  surface 
  of 
  the 
  body 
  (fig. 
  135). 
  If 
  

   the 
  insect 
  escapes 
  from 
  the 
  flower 
  and 
  visits 
  another, 
  when 
  

   it 
  thrusts 
  its 
  foot 
  through 
  a 
  corpusculum 
  slit 
  of 
  the 
  second 
  

   flower 
  the 
  pollen 
  masses 
  already 
  attached 
  to 
  the 
  foot 
  become 
  

   torn 
  away. 
  The 
  pollen 
  masses 
  thus 
  detached 
  are 
  left 
  in 
  con- 
  

   tact 
  with 
  the 
  stigma 
  of 
  the 
  second 
  flower, 
  and 
  in 
  this 
  way 
  most 
  

   effectively 
  secure 
  cross-pollination. 
  

  

  