﻿6 
  Howe: 
  Moxosporangial 
  discs 
  in 
  Li 
  agora 
  

  

  4 
  

  

  the 
  largest 
  of 
  the 
  four 
  species 
  named, 
  they 
  may 
  occasionally 
  reach 
  

   a 
  diameter 
  of 
  nearly 
  400 
  )u. 
  The 
  monosporangia 
  are 
  ellipsoid, 
  

   ovoid, 
  or 
  obovoid, 
  and 
  are 
  usually 
  13-26 
  /x 
  long 
  and 
  13-18 
  ju 
  

   broad, 
  measuring 
  protoplasts 
  only. 
  To 
  what 
  these 
  monosporangia 
  

   give 
  rise 
  on 
  germination 
  has 
  not 
  been 
  determined 
  but 
  there 
  seems 
  

  

  some 
  

  

  discs 
  like 
  those 
  from 
  which 
  they 
  sprang. 
  Species 
  of 
  Liagora 
  offer 
  

   a 
  favorable 
  matrix 
  for 
  the 
  germination 
  of 
  various 
  filamentous 
  

   algae, 
  including 
  species 
  of 
  Acrochaetium, 
  Ceramium, 
  and 
  other 
  

   Rhodophyceae, 
  and 
  inferences 
  that 
  young 
  sporelings 
  associated 
  

   with 
  a 
  Liagora 
  represent 
  stages 
  in 
  development 
  of 
  the 
  Liagora 
  

   itself 
  demand 
  rigorous 
  confirmation, 
  such 
  as 
  might 
  be 
  supplied 
  by 
  

   cultures 
  or 
  by 
  the 
  presence 
  of 
  a 
  complete 
  series 
  of 
  developmental 
  

   Stages. 
  In 
  this 
  connection, 
  however, 
  it 
  may 
  be 
  remarked 
  that 
  

   the 
  almost 
  constant 
  association 
  of 
  Acrochaetlum-Yike 
  forms 
  with 
  

   various 
  species 
  of 
  Liagora 
  is 
  a 
  suspicious 
  circumstance 
  that 
  deserves 
  

   further 
  investigation. 
  

  

  In 
  offering 
  the 
  above 
  explanation 
  of 
  the 
  origin 
  of 
  the 
  peculiar 
  

   monosporangium-bearing 
  discs 
  of 
  certain 
  species 
  of 
  Liagora, 
  the 
  

   writer 
  realizes 
  that 
  he 
  may 
  be 
  charged 
  with 
  having 
  mistaken 
  

   accidental 
  contact 
  for 
  organic 
  continuity. 
  It 
  would 
  be 
  easier, 
  

   more 
  conventional, 
  and 
  (a 
  priori) 
  more 
  probable 
  to 
  regard 
  the 
  

   discs 
  as 
  independent 
  or 
  obligate 
  epi-endophytes. 
  Early 
  in 
  his 
  

   acquaintance 
  with 
  them, 
  the 
  writer 
  was 
  at 
  one 
  time 
  on 
  the 
  point 
  

   of 
  describing 
  them 
  as 
  representing 
  a 
  new 
  genus 
  of 
  uncertain 
  

   family, 
  but 
  was 
  deterred 
  by 
  observing 
  that 
  the 
  character 
  of 
  the 
  

   discs, 
  particularly 
  of 
  their 
  cells 
  and 
  cell 
  walls 
  varied 
  according 
  to 
  

   the 
  species 
  on 
  which 
  they 
  occurred, 
  and 
  that 
  the 
  discs 
  were 
  

   progressively 
  older 
  from 
  base 
  to 
  apex 
  of 
  the 
  Liagora 
  thallus, 
  the 
  

   early 
  stages 
  being 
  found 
  only 
  at 
  the 
  extreme 
  apices. 
  The 
  chro- 
  

   matophores, 
  too, 
  seemed 
  similar, 
  except 
  that 
  those 
  of 
  the 
  discs 
  

   were 
  more 
  red 
  than 
  those 
  of 
  the 
  vegetative 
  cells 
  of 
  the 
  Liagora, 
  

   often 
  as 
  red 
  as 
  those 
  of 
  the 
  carpospores. 
  After 
  much 
  searching, 
  

   indications 
  that 
  the 
  discs 
  could 
  be 
  traced 
  back 
  to 
  certain 
  cells 
  of 
  

   the 
  Liagora 
  thallus 
  were 
  observed, 
  as 
  shown 
  in 
  the 
  accompanying 
  

   figures. 
  These 
  observed 
  evidences 
  of 
  direct 
  continuity 
  were 
  

  

  nalogy 
  

  

  knows 
  

  

  