﻿1 
  

  

  1890.] 
  BOTANICAL 
  GAZETTE. 
  327 
  

  

  or 
  from 
  the 
  shores. 
  In 
  such 
  cases 
  the 
  uppermost 
  leaves 
  are 
  

   green 
  and 
  rest 
  upon 
  the 
  water, 
  the 
  immersed 
  ones 
  shining, 
  

   all 
  usually 
  coriaceous 
  and 
  with 
  short 
  petioles. 
  

  

  P. 
  pusillus 
  was 
  detected 
  in 
  pools, 
  and 
  in 
  East 
  Two 
  Rivers 
  

   the 
  related 
  species 
  P. 
  mucronatus 
  Schrad. 
  P. 
  Pennsyl- 
  

   vanicus 
  was 
  common, 
  some 
  specimens 
  of 
  which, 
  taken 
  from 
  

   West 
  Two 
  Rivers, 
  had 
  the 
  immersed 
  leaves 
  7-nerved, 
  the 
  5- 
  

   nerved 
  being 
  the 
  usual 
  kind. 
  In 
  the 
  same 
  stream 
  P. 
  rufescens 
  

   was 
  frequent, 
  and 
  the 
  species 
  rather 
  rare 
  at 
  the 
  west, 
  P. 
  oh- 
  

   iusi/olms 
  Mert. 
  & 
  Koch. 
  It 
  was 
  the 
  first 
  time 
  I 
  had 
  met 
  with 
  

   it 
  in 
  its 
  place 
  of 
  growth. 
  The 
  stems 
  were 
  quite 
  robust, 
  from 
  

   two 
  to 
  three 
  feet 
  long 
  ; 
  the 
  leaves 
  very 
  uniform 
  in 
  length, 
  or 
  

   about 
  three 
  inches, 
  acute 
  or 
  acutish, 
  giving 
  it 
  the 
  appearance 
  

   of 
  small-leaved 
  forms 
  of 
  P. 
  zosier<Bfolius 
  Schum._ 
  It 
  was 
  

   fruiting 
  abundantly, 
  maturing 
  from 
  12 
  to 
  22 
  nutlets 
  in 
  oblong 
  

   capitate 
  spikes, 
  half 
  an 
  inch 
  in 
  length, 
  on 
  peduncles 
  fuhy 
  

   three 
  times 
  as 
  long. 
  These 
  peduncles, 
  long 
  as 
  compared 
  with 
  

   the 
  length 
  of 
  the 
  head, 
  I 
  have 
  noticed 
  in 
  specimens 
  from 
  the 
  

   east 
  by 
  exchange, 
  and 
  the 
  descriptions 
  err 
  by 
  limiting 
  them 
  

   to 
  about 
  the 
  length 
  of 
  the 
  head. 
  This 
  is 
  as 
  far 
  west 
  as 
  it 
  

   seems 
  to 
  have 
  been 
  reported 
  in 
  our 
  limits, 
  unless 
  recently 
  

   found, 
  though 
  found 
  about 
  as 
  far 
  north, 
  in 
  Gratiot 
  l^ake, 
  

   Keeweenaw 
  Peninsula. 
  Prof. 
  J. 
  C. 
  Arthur 
  had 
  previously 
  

   found 
  it, 
  with 
  most 
  of 
  those 
  already 
  mentioned, 
  in 
  the 
  ^me 
  

   locality 
  as 
  seen 
  by 
  his 
  "Report 
  on 
  botanical 
  work 
  in 
  Min- 
  

   Tiesota 
  for 
  the 
  year 
  1886."=^ 
  . 
  ^ 
  ... 
  • 
  

  

  Another 
  aquatic 
  is 
  worthv 
  of 
  mention, 
  a 
  form 
  of 
  bag^ttana 
  

   -"ariabiUs^Engel., 
  with 
  floating 
  leaves, 
  found 
  m 
  the 
  same 
  

   stream. 
  Prof. 
  Arthur 
  also 
  collected 
  it 
  from 
  this 
  locality, 
  it 
  

   does 
  not 
  seem 
  to 
  be 
  mentioned 
  in 
  the 
  text-books, 
  or 
  m 
  tne 
  

   botanical 
  works 
  of 
  Engelmann, 
  though 
  he 
  gives 
  a 
  vanet} 
  

   fluitans 
  for 
  S. 
  heterophylla 
  and 
  S. 
  calycina. 
  I^/PPf 
  J^'l^X 
  

   ^tis 
  considerably 
  different 
  from 
  the 
  common 
  kind, 
  but 
  naicu} 
  

   varies 
  from 
  the 
  type 
  except 
  in 
  this 
  respect 
  : 
  the 
  f 
  thers 
  are 
  

   about 
  the 
  length 
  of 
  the 
  filaments, 
  rather 
  broadly 
  oblong 
  , 
  

   facts 
  3 
  to 
  4; 
  lower 
  whorls 
  of 
  flowers 
  sometimes 
  dioeuous, 
  

   leaves 
  sagittate, 
  resting 
  on 
  the 
  water, 
  the 
  round, 
  senciei 
  

   petioles 
  too 
  weak 
  to 
  stand 
  erect 
  when 
  removed 
  ^^-^jn 
  the 
  xv 
  ater, 
  

   to 
  whose 
  depth 
  they 
  correspond 
  in 
  length, 
  those 
  at 
  io;;^f;j 
  

   ^^g 
  from 
  2| 
  to 
  3 
  feet. 
  The 
  scapes 
  are 
  also 
  slender, 
  but 
  sup 
  

   port 
  the 
  flowers 
  and 
  fruit 
  above 
  the 
  water. 
  I 
  have 
  oc 
  

   sionally 
  seen 
  it 
  in 
  other 
  places, 
  as 
  about 
  Chicago, 
  but 
  not 
  

   flower 
  or 
  fruit. 
  It 
  was 
  not 
  uncommon 
  in 
  the 
  stream, 
  it 
  m 
  } 
  

   deserve 
  the 
  varietal 
  distinction 
  fl 
  u 
  i 
  t 
  a 
  n 
  s^_unlessjtji^^ 
  

  

  ^ 
  -^^ 
  ■ 
  — 
  ' 
  ' 
  "^ 
  It 
  q 
  Qr 
  Paul 
  188"» 
  

  

  Geological 
  and 
  Natural 
  History 
  Survey 
  of 
  Minnesota. 
  Bulletin 
  No. 
  .\ 
  ■ 
  

  

  