﻿450 
  Ever-sporting 
  Varieties 
  

  

  The 
  desert 
  of 
  Kaits, 
  in 
  Northern 
  Ceylon, 
  

   nourishes 
  on 
  its 
  dry 
  and 
  torrid 
  sands 
  some 
  

   species, 
  represented 
  by 
  a 
  large 
  number 
  of 
  in- 
  

   dividuals, 
  together 
  with 
  some 
  rarer 
  plants. 
  

   The 
  commonest 
  forms 
  are 
  Erigeron 
  asteroides, 
  

   Vernonia 
  cinerea, 
  Laurea 
  pinnatifida, 
  Vicoa 
  au- 
  

   riculatG, 
  Heylandia 
  latebrosa 
  and 
  Clirysopo- 
  

   gon 
  montanns. 
  In 
  direct 
  contrast 
  with 
  the 
  or- 
  

   dinary 
  desert-types 
  they 
  have 
  a 
  thin 
  epidermis, 
  

   with 
  exposed 
  stomata, 
  features 
  that 
  ordinarily 
  

   were 
  characteristic 
  of 
  species 
  of 
  moister 
  re- 
  

   gions. 
  They 
  are 
  annuals, 
  growing 
  rapidly, 
  

   blooming 
  and 
  ripening 
  their 
  seeds 
  before 
  the 
  

   height 
  of 
  the 
  dry 
  season. 
  Evidently 
  they 
  are 
  

   to 
  be 
  considered 
  as 
  the 
  remainder 
  of 
  the 
  flora 
  

   of 
  a 
  previous 
  period, 
  when 
  the 
  soil 
  had 
  not 
  yet 
  

   become 
  arid. 
  They 
  might 
  be 
  called 
  relics. 
  Of 
  

   course 
  they 
  are 
  small 
  and 
  dwarf-like, 
  when 
  com- 
  

   pared 
  with 
  allied 
  forms. 
  

  

  These 
  curious 
  little 
  desert-plants 
  disprove 
  

   the 
  Nagelian 
  views 
  in 
  two 
  important 
  points. 
  

   First, 
  thev 
  show 
  that 
  extreme 
  conditions 
  do 
  not 
  

  

  e> 
  

  

  necessarily 
  change 
  the 
  organisms 
  subjected 
  to 
  

   them, 
  in 
  a 
  desirable 
  direction. 
  During 
  the 
  

   many 
  centuries 
  that 
  these 
  plants 
  must 
  have 
  ex- 
  

   isted 
  in 
  the 
  desert 
  in 
  annual 
  generations, 
  no 
  

   single 
  feature 
  in 
  the 
  anatomical 
  structure 
  has 
  

   become 
  changed. 
  Hence 
  the 
  conclusion 
  that 
  

   small 
  leaves, 
  abundant 
  rootstocks 
  and 
  short 
  

  

  