﻿108 
  

  

  Nichols: 
  The 
  vegetation 
  of 
  Connecticut 
  

  

  3. 
  Associations 
  of 
  the 
  supralittoral 
  region 
  

  

  The 
  associations 
  of 
  rocky 
  sea 
  bluffs. 
  — 
  Like 
  the 
  sublittoral 
  and 
  

   the 
  Httoral 
  regions, 
  the 
  supralittoral 
  (Fig. 
  5) 
  can 
  be 
  divided 
  into 
  

   a 
  lower 
  and 
  an 
  upper 
  "sub-region/' 
  The 
  lower 
  supralittoral 
  

   comprises 
  a 
  belt 
  immediately 
  above 
  mean 
  high 
  tide 
  mark 
  in 
  which, 
  

   except 
  frequently 
  for 
  an 
  impoverished 
  growth 
  of 
  Enteromorpha 
  

   spp., 
  the 
  rock 
  surface 
  is 
  practically 
  destitute 
  of 
  vegetation 
  of 
  

   any 
  description. 
  Conditions 
  here 
  are 
  too 
  dry 
  for 
  seaweeds 
  and 
  

   too 
  salty 
  for 
  lichens 
  and 
  mosses, 
  while 
  the 
  development 
  of 
  halo- 
  

  

  FiG. 
  5. 
  Zonation 
  of 
  plant 
  associations 
  along 
  a 
  rock-bound 
  shore; 
  East 
  Haven. 
  

   The 
  following 
  zones 
  are 
  apparent, 
  from 
  below 
  upward: 
  (i) 
  Ftuus 
  and 
  AscophyUn^ 
  

   of 
  lower 
  littoral; 
  (2) 
  Enteromorpha, 
  etc., 
  of 
  upper 
  littoral; 
  (3) 
  plantless 
  lower 
  supralit- 
  

   toral; 
  (4) 
  lichen-moss 
  zone 
  of 
  upper 
  supralittoral, 
  with 
  seed 
  plants 
  abo^e. 
  

  

  phytic 
  seed 
  plants 
  is 
  prevented 
  primarily 
  by 
  the 
  mechanical 
  

   action 
  of 
  waves 
  and 
  ice 
  in 
  times 
  of 
  heavy 
  sea. 
  This 
  plantless 
  

   belt 
  varies 
  in 
  width: 
  along 
  the 
  more 
  exposed 
  shores 
  it 
  may 
  extend 
  

   upward 
  for 
  a 
  distance 
  of 
  twelve 
  or 
  fifteen 
  feet; 
  in 
  less 
  exposed 
  

   situations 
  it 
  may 
  be 
  quite 
  narrow. 
  

  

  The 
  upper 
  supralittoral 
  extends 
  from 
  the 
  unner 
  edee 
  of 
  the 
  

  

  