﻿96 
  Nichols: 
  The 
  vegetation 
  of 
  Connecticut 
  

  

  m 
  

  

  the 
  geologic 
  past 
  are 
  in 
  part 
  responsible 
  for 
  the 
  larger 
  features 
  in 
  

  

  more 
  

  

  physiographic 
  agencies 
  of 
  today. 
  The 
  wearing 
  away 
  of 
  the 
  shore 
  

   here, 
  and 
  its 
  building 
  up 
  there, 
  the 
  development 
  in 
  exposed 
  situa- 
  

   tions 
  of 
  coastal 
  swamps, 
  beaches 
  and 
  dunes 
  — 
  these 
  and 
  similar 
  

   phenomena 
  are 
  due 
  primarily 
  to 
  the 
  activity 
  of 
  waves, 
  of 
  tidal 
  and 
  

   other 
  currents, 
  and, 
  in 
  the 
  case 
  of 
  the 
  dunes, 
  of 
  wind. 
  Erosion 
  

   and 
  deposition, 
  therefore, 
  have 
  an 
  important 
  influence 
  on 
  the 
  

   plant 
  associations, 
  since 
  the 
  character 
  of 
  seaside 
  vegetation, 
  both 
  

   above 
  and 
  below 
  high 
  tide 
  level, 
  bears 
  an 
  intimate 
  relation 
  to 
  

   the 
  physical 
  nature 
  of 
  the 
  substratum. 
  Thus, 
  the 
  plant 
  associa- 
  

   tions 
  of 
  sandy 
  shores 
  differ 
  markedly 
  from 
  those 
  of 
  muddy 
  shores, 
  

   and, 
  again, 
  from 
  those 
  of 
  rocky 
  shores. 
  Seaweeds, 
  for 
  example, 
  

   are 
  most 
  luxuriantly 
  developed 
  on 
  rocky 
  or 
  stony 
  bottoms; 
  on 
  

   sandy 
  or 
  muddy 
  bottoms 
  they 
  may 
  be 
  almost 
  absent; 
  and 
  so 
  on.* 
  

  

  Other 
  agencies.— 
  The 
  influence 
  of 
  ice 
  and 
  of 
  salt 
  spray 
  are 
  

   further 
  factors 
  which 
  may 
  contribute 
  materially 
  to 
  the 
  character 
  

   of 
  plant 
  associations 
  along 
  the 
  seacoast. 
  Floating 
  ice, 
  in 
  addition 
  

   to 
  the 
  indirect 
  effect 
  which 
  it 
  may 
  exert 
  by 
  supplementing 
  the 
  

   abrading 
  action 
  of 
  the 
  waves, 
  scrapes 
  exposed 
  rocks 
  bare 
  of 
  

   seaweeds 
  and 
  in 
  other 
  ways 
  affects 
  the 
  shore 
  vegetation 
  within 
  its 
  

   reach. 
  Salt 
  spray 
  dashed 
  up 
  by 
  waves 
  or 
  wind 
  sometimes 
  makes 
  

   possible 
  the 
  existence 
  of 
  certain 
  marine 
  algae 
  even 
  above 
  high 
  

   tide 
  mark, 
  at 
  the 
  same 
  time 
  preventing 
  the 
  development 
  here 
  of 
  

   non-halophytic 
  land 
  plants 
  or 
  at 
  any 
  rate 
  having 
  a 
  more 
  or 
  less 
  

   pronounced 
  effect 
  on 
  their 
  growth. 
  The 
  sterility 
  in 
  mineral 
  

   nutrients 
  of 
  wave- 
  and 
  wind-deposited 
  sand 
  is 
  very 
  likely 
  re- 
  

   sponsible, 
  in 
  part 
  at 
  least, 
  for 
  the 
  peculiarities 
  of 
  beach 
  and 
  dune 
  

  

  vegetation. 
  

  

  ■ 
  

  

  C. 
  Atmospheric 
  influences 
  

  

  ^ 
  Various 
  atmospheric 
  agencies 
  which 
  tend 
  to 
  accelerate 
  tran- 
  

   spiration, 
  especially 
  strong 
  winds 
  and, 
  during 
  certain 
  seasons 
  of 
  

   the 
  year, 
  intense 
  heat, 
  may 
  affect 
  to 
  a 
  marked 
  degree 
  the 
  habit 
  

   and 
  structure 
  of 
  terrestrial 
  plants 
  along 
  the 
  seacoast. 
  Strong 
  

   illumination, 
  likewise, 
  may 
  be 
  an 
  influential 
  factor. 
  The 
  effect 
  

  

  * 
  For 
  purposes 
  of 
  convenience, 
  througho^ 
  the 
  present 
  paper 
  and 
  the 
  next 
  ^ 
  

  

  a 
  dTstinction 
  is 
  made 
  between 
  shore 
  and 
  boUom. 
  The 
  application 
  of 
  the 
  term 
  shore 
  is 
  

  

  restricted 
  to 
  areas 
  above 
  low 
  tide 
  level, 
  areas 
  below 
  low 
  tide 
  level 
  being 
  referred 
  to 
  

   as 
  bottom. 
  

  

  