﻿G-. 
  M. 
  Thomson. 
  — 
  On 
  the 
  Fertilization 
  of 
  some 
  New 
  Zealand 
  Orchids. 
  423 
  

  

  the 
  stigma, 
  tliiis 
  ensuring 
  fertilization. 
  I 
  found 
  tins 
  to 
  be 
  the 
  case 
  in 
  

   several 
  hundred 
  flowers 
  "which 
  I 
  examined. 
  The 
  position 
  of 
  the 
  laLellum 
  

   on 
  the 
  underside 
  of 
  this 
  flower 
  is 
  caused 
  by 
  the 
  usual 
  twisting 
  of 
  the 
  pedicel 
  

   or 
  ovary, 
  which 
  is 
  so 
  common 
  in 
  many 
  orchids. 
  But 
  in 
  young 
  buds 
  the 
  

   posterior 
  sepal 
  is 
  lowest 
  and 
  placed 
  on 
  the 
  side 
  farthest 
  from 
  the 
  axis 
  of 
  the 
  

   spike 
  ; 
  and 
  it 
  is 
  during 
  the 
  gradual 
  maturing 
  of 
  the 
  flower 
  that 
  the 
  twisting 
  

   takes 
  place, 
  so 
  that, 
  by 
  the 
  time 
  it 
  opens, 
  the 
  labellum 
  and 
  posterior 
  sepal 
  

   have 
  changed 
  places. 
  

  

  This 
  species, 
  as 
  might 
  be 
  expected 
  from 
  its 
  facilities 
  for 
  reproduction, 
  is 
  

   one 
  of 
  the 
  commonest 
  plants 
  of 
  the 
  class. 
  

  

  (5.) 
  Caladenia 
  bi/olia. 
  

  

  Ghiloglottis 
  traversii, 
  Mueller. 
  

   This 
  is 
  a 
  most 
  abundant 
  orchid 
  in 
  upland 
  districts 
  at 
  an 
  elevation 
  of 
  

   1500 
  to 
  3000 
  feet. 
  The 
  flower 
  is 
  solitar}'- 
  on 
  an 
  erect 
  scape, 
  three 
  to 
  four 
  

   inches 
  in 
  height. 
  The 
  upper 
  sepal 
  is 
  obtuse, 
  somewhat 
  arched 
  forward, 
  and 
  

   slightly 
  keeled. 
  The 
  lateral 
  sepals 
  are 
  placed 
  under 
  the 
  labellum, 
  and 
  

   extend 
  forward 
  almost 
  horizontally. 
  The 
  labellum 
  is 
  broad 
  ; 
  on 
  each 
  side 
  

   of 
  the 
  expanded 
  portion 
  is 
  a 
  yellow-coloured 
  patch 
  bearing 
  two 
  or 
  three 
  

   brownish 
  spots, 
  while 
  extending 
  from 
  the 
  middle 
  to 
  the 
  base 
  are 
  two 
  rows 
  

   of 
  yellow 
  glands. 
  The 
  column 
  is 
  long 
  and 
  erect, 
  slightly 
  winged 
  above, 
  

   and 
  bearing 
  a 
  terminal 
  anther 
  which 
  encloses 
  four 
  poUinia. 
  The 
  stigma 
  is 
  

   rounded 
  and 
  slightly 
  hoUowed 
  out, 
  and 
  is 
  placed 
  in 
  close 
  contiguity 
  to 
  the 
  

   anther. 
  The 
  arrangement 
  of 
  the 
  parts 
  is 
  so 
  simple 
  that 
  an 
  insect 
  alighting 
  

   on 
  the 
  labellum 
  and 
  advancing 
  its 
  head 
  into 
  the 
  base 
  of 
  the 
  flower 
  could 
  

   hardly 
  fail 
  to 
  remove 
  the 
  pollinia 
  ; 
  nor 
  could 
  one 
  entering 
  with 
  pollen 
  on 
  

   its 
  head 
  fail 
  to 
  leave 
  these 
  on 
  the 
  stigma, 
  for 
  in 
  withdrawing 
  pollinia 
  

   from 
  a 
  flower 
  they 
  are 
  always 
  slightly 
  depressed 
  by 
  the 
  cap 
  of 
  the 
  anther. 
  

   The 
  pollen 
  of 
  this 
  plant 
  is 
  very 
  incoherent, 
  and 
  the 
  lower 
  surface 
  of 
  the 
  

   stigma 
  projects 
  a 
  little, 
  so 
  that 
  I 
  am 
  inclined 
  to 
  think 
  self-fertilization 
  takes 
  

   place 
  in 
  flowers 
  which 
  have 
  not 
  been 
  visited 
  by 
  insects. 
  The 
  majority 
  of 
  

   the 
  flowers 
  appear 
  to 
  set 
  good 
  capsules, 
  and 
  flowers 
  which 
  I 
  fertilized 
  

   artificially, 
  produced 
  good 
  full 
  seed-vessels. 
  I 
  examined 
  one 
  sunny 
  day 
  

   twenty-two 
  flowers 
  growing 
  in 
  the 
  open 
  ; 
  of 
  these 
  only 
  three 
  had 
  both 
  

   pollinia 
  removed 
  ; 
  in 
  one 
  the 
  pollinia 
  were 
  removed 
  from 
  one 
  anther 
  lobe 
  ; 
  

   in 
  five 
  others 
  the 
  pollen 
  masses 
  appeared 
  more 
  or 
  less 
  disturbed 
  ; 
  while 
  in 
  

   the 
  remaining 
  thirteen 
  the 
  anthers 
  were 
  untouched. 
  

  

  (6.) 
  Pierostylis 
  hanlcsii. 
  

  

  The 
  fertilization 
  of 
  the 
  flowers 
  of 
  this 
  genus 
  has 
  been 
  so 
  well 
  described 
  

   by 
  Mr. 
  Cheeseman, 
  in 
  the 
  Trans. 
  N.Z. 
  Inst., 
  Vol. 
  V., 
  p. 
  352, 
  that 
  I 
  cannot 
  

   •v\ 
  ell 
  add 
  to 
  it, 
  but 
  my 
  observations 
  on 
  them 
  more 
  than 
  ever 
  induce 
  me 
  to 
  

   consider 
  that 
  there 
  has 
  been 
  an 
  unusual 
  scarcity 
  of 
  insect 
  life 
  during 
  the 
  

  

  