﻿430 
  T. 
  Holm 
  — 
  Studies 
  in 
  the 
  Cyperacece. 
  

  

  tris 
  and 
  others. 
  The 
  internodes 
  are 
  distinct 
  and 
  partly 
  cov- 
  

   ered 
  with 
  rudimentary, 
  sheathing 
  leaves. 
  Relatively 
  strong 
  

   roots 
  develop 
  above 
  the 
  nodes, 
  especially 
  from 
  the 
  lower 
  sur- 
  

   face. 
  Several 
  stems, 
  above-ground, 
  arise 
  from 
  the 
  rhizome 
  

   and 
  they 
  show 
  a 
  structure 
  very 
  different 
  from 
  what 
  we 
  are 
  

   accustomed 
  to 
  see 
  in 
  the 
  Cyperacece, 
  having 
  numerous 
  cylindric 
  

   and 
  hollow 
  internodes. 
  As 
  we 
  remember 
  the 
  stem, 
  above- 
  

   ground, 
  of 
  the 
  Cyperacece, 
  it 
  is 
  generally 
  solid 
  and 
  forms 
  a 
  dis- 
  

   tinct, 
  often 
  very 
  long 
  scape. 
  Vegetative 
  branches 
  do 
  not 
  com- 
  

   monly 
  develop 
  upon 
  the 
  stem, 
  above-ground, 
  but 
  we 
  have 
  

   noticed, 
  however, 
  a 
  few 
  cases 
  where 
  a 
  small, 
  horizontally 
  creep- 
  

   ing 
  branch 
  had 
  developed 
  from 
  the 
  axil 
  of 
  one 
  of 
  the 
  stem- 
  

   leaves. 
  Such 
  secondary 
  branches 
  showed 
  the 
  same 
  kind 
  of 
  

   ramification 
  and 
  structure 
  as 
  the 
  rhizome. 
  

  

  The 
  leaves 
  of 
  Dulichium 
  are 
  either 
  reduced 
  to 
  tubular 
  

   sheaths 
  upon 
  the 
  rhizome 
  and 
  at 
  the 
  base 
  of 
  the 
  stems, 
  or 
  they 
  

   are 
  normally 
  developed 
  with 
  a 
  linear 
  blade, 
  a 
  short, 
  crescent- 
  

   shaped 
  ligule 
  and 
  a 
  long 
  tubular 
  sheath. 
  

  

  By 
  considering 
  the 
  inflorescence 
  we 
  find 
  the 
  flowers 
  arranged 
  

   biseriately 
  in 
  spikes. 
  Each 
  flower 
  is 
  perfect, 
  supported 
  by 
  a 
  

   scale-like 
  bract, 
  and 
  has 
  commonly 
  eight 
  downwardly 
  barbed 
  

   bristles, 
  which 
  are 
  a 
  little 
  longer 
  than 
  the 
  style 
  of 
  the 
  ovary. 
  

   The 
  three 
  stamens 
  have 
  long 
  filaments 
  and 
  reach 
  above 
  the 
  

   apex 
  of 
  the 
  bristles. 
  The 
  style 
  is 
  papuliferous 
  in 
  its 
  entire 
  

   length 
  like 
  the 
  two 
  filiform 
  stigmata 
  ; 
  the 
  achenium 
  is 
  at 
  

   maturity 
  oblong, 
  flattened, 
  shortly 
  stipitate, 
  and 
  the 
  remaining 
  

   style 
  forms 
  a 
  slender 
  beak. 
  By 
  returning 
  to 
  the 
  inflorescence, 
  

   we 
  have 
  stated 
  above, 
  that 
  the 
  flowers 
  are 
  arranged 
  in 
  from 
  

   six- 
  to 
  eight-flowered 
  spikes, 
  which 
  again 
  are 
  arranged 
  biseri- 
  

   ately 
  along 
  a 
  short 
  rhachis, 
  which 
  is 
  the 
  continuation 
  of 
  a 
  short 
  

   peduncle, 
  almost 
  entirely 
  inclosed 
  by 
  the 
  sheath 
  of 
  the 
  sup- 
  

   porting 
  leaf. 
  The 
  inflorescence 
  consists 
  then 
  of 
  one 
  terminal 
  

   and 
  about 
  eight 
  lateral 
  spikes, 
  these 
  last 
  being 
  supported 
  by 
  

   scale-like 
  bracts, 
  but 
  destitute 
  of 
  any 
  prophylla. 
  A 
  prophyllon, 
  

   clado-prophyllon, 
  is, 
  however, 
  to 
  be 
  observed 
  at 
  the 
  very 
  base 
  

   of 
  the 
  peduncle 
  ; 
  it 
  is 
  very 
  short 
  and 
  tubular 
  with 
  the 
  apex 
  

   oblique. 
  While 
  this 
  general 
  structure 
  applies 
  to 
  all 
  the 
  lateral 
  

   inflorescences 
  of 
  Dulichium, 
  it 
  also 
  agrees 
  with 
  the 
  terminal 
  

   one, 
  with 
  but 
  one 
  exception, 
  that 
  no 
  prophyllon 
  is 
  developed 
  at 
  

   the 
  base 
  of 
  the 
  peduncle, 
  this 
  being 
  the 
  immediate 
  continua- 
  

   tion 
  of 
  the 
  main 
  stem 
  itself. 
  By 
  comparing 
  now 
  the 
  inflores- 
  

   cences 
  of 
  our 
  genus 
  with 
  those 
  of 
  Cyperus, 
  the 
  difference 
  

   consists 
  merely 
  in 
  that 
  they 
  are 
  scattered 
  along 
  the 
  stem 
  in 
  Du- 
  

   lichium, 
  while 
  in 
  Cyperus 
  they 
  are 
  gathered 
  towards 
  the 
  apex 
  

   of 
  the 
  long 
  scape. 
  In 
  this 
  way 
  the 
  inflorescences 
  in 
  Cyperus 
  

   form 
  like 
  an 
  umbel 
  with 
  the 
  outer 
  (the 
  lowest-situated) 
  borne 
  

   on 
  longer 
  peduncles 
  than 
  the 
  inner 
  ones, 
  while 
  the 
  terminal 
  

   inflorescence 
  is 
  almost 
  sessile 
  in 
  the 
  center 
  of 
  the 
  umbel. 
  

  

  