﻿546 
  

  

  Nichols: 
  The 
  vegetation 
  of 
  Connecticut 
  

  

  occurrence 
  in 
  salt 
  meadows, 
  and 
  a 
  similar 
  explanation 
  accounts, 
  

   in 
  large 
  measure, 
  for 
  the 
  presence 
  in 
  the 
  midlittoral 
  marsh, 
  in 
  

   areas 
  otherwise 
  densely 
  populated 
  by 
  salt 
  marsh 
  grass, 
  of 
  open 
  

   patches 
  (see 
  Fig. 
  5), 
  bare 
  and 
  muddy 
  at 
  low 
  tide 
  and 
  frequently 
  of 
  

   considerable 
  dimensions. 
  It 
  may 
  perhaps 
  account 
  also 
  for 
  the 
  

   origin 
  of 
  some 
  of 
  the 
  shallower 
  depressions 
  in 
  the 
  meadows 
  of 
  the 
  

   upper 
  littoral; 
  but 
  many, 
  if 
  not 
  most, 
  of 
  these 
  latter, 
  and 
  the 
  

   majority, 
  if 
  not 
  all, 
  of 
  the 
  deeper 
  depressions, 
  have 
  arisen 
  in 
  a 
  very 
  

  

  Fig. 
  10. 
  Development 
  of 
  pans 
  through 
  local 
  invasion 
  of 
  tidal 
  creeks 
  and 
  ditches 
  

   by 
  Spartina 
  glabra. 
  Westbrook. 
  In 
  view 
  to 
  right 
  a 
  former 
  meandering 
  creek 
  has 
  

  

  become 
  quite 
  obliterated. 
  Ditch 
  in 
  center 
  has 
  become 
  completely 
  obstructed; 
  the 
  

   one 
  to 
  left 
  is 
  still 
  open. 
  

  

  different 
  manner. 
  

  

  Joh 
  

  

  ('17) 
  on 
  the 
  origin 
  of 
  these 
  "pans" 
  (as 
  the 
  depressions 
  are 
  termed 
  

   by 
  them 
  and 
  by 
  other 
  European 
  ecologists) 
  in 
  the 
  salt 
  marshes 
  

   of 
  the 
  Dovey 
  Estuary, 
  in 
  Wales, 
  have 
  fully 
  confirmed 
  con- 
  

   clusions 
  which 
  the 
  writer 
  had 
  already 
  reached 
  regarding 
  their 
  

   origin 
  in 
  the 
  salt 
  marshes 
  along 
  the 
  Connecticut 
  coast. 
  

  

  Avoiding 
  detail, 
  as 
  far 
  as 
  possible, 
  the 
  pans 
  of 
  the 
  upper 
  

   littoral 
  meadows 
  may 
  be 
  divided 
  into 
  two 
  groups, 
  with 
  reference 
  

   to 
  their 
  mode 
  of 
  origin: 
  primary 
  pans, 
  which 
  are 
  formed 
  during 
  

   the 
  development 
  of 
  the 
  marsh; 
  and 
  secondary 
  pans, 
  which 
  arise 
  

   subsequently. 
  Primary 
  pans 
  are 
  formed 
  in 
  somewhat 
  the 
  follow- 
  

   ing 
  manner. 
  During 
  the 
  early 
  development 
  of 
  the 
  marsh, 
  the 
  

  

  