﻿3i6 
  BOTANICAL 
  GAZETTE. 
  [ 
  December, 
  

  

  immediately 
  as 
  they 
  dry, 
  leaving 
  scarcely 
  a 
  vestige 
  of 
  a 
  re- 
  

   ceptacle, 
  while 
  the 
  same 
  species 
  late 
  in 
  October 
  will 
  develop 
  

   closely 
  aggregated, 
  obovate, 
  almost 
  clavate 
  sporangia, 
  nearly 
  

   sessile 
  or 
  with 
  quite 
  short 
  stipes, 
  which 
  rupture 
  slowly 
  several 
  

   days 
  after 
  maturity, 
  leaving 
  a 
  very 
  deep 
  funnel-shaped 
  re- 
  

   ceptacle. 
  

  

  Among 
  the 
  Calcareae, 
  the 
  amount 
  of 
  lime 
  in 
  solution 
  

   available 
  for 
  the 
  use 
  of 
  the 
  plasmodium 
  will 
  greatly 
  influence 
  

   the 
  degree 
  to 
  which 
  lime 
  granules 
  are 
  found 
  in 
  the 
  capilhtium 
  

   and 
  sporangium 
  walls, 
  thus 
  producing 
  great 
  apparent 
  vana- 
  

   tion 
  in 
  structure. 
  Careful 
  examination 
  in 
  these 
  cases, 
  how- 
  

   ever, 
  will 
  show 
  that 
  the 
  essentials 
  of 
  structure 
  are 
  the 
  same, 
  

   and 
  the 
  amount 
  of 
  lime 
  onlj^ 
  a 
  variable 
  and 
  non-important 
  

   factor. 
  

  

  In 
  the 
  plasmodial 
  stage 
  of 
  the 
  Myxomycetes, 
  however, 
  no 
  

   such 
  tendency 
  to 
  variation 
  exists, 
  and 
  the 
  plasmodium 
  ol 
  

   every 
  species 
  which 
  I 
  have 
  observed 
  is 
  unvarying 
  in 
  com 
  

   and 
  other 
  physical 
  characters. 
  It 
  is 
  true, 
  the 
  normal 
  color 
  

   may 
  be 
  temporarily 
  affected 
  by 
  adventitious 
  coloring 
  mattci 
  

   picked 
  up 
  by 
  the 
  plasmodium 
  during 
  its 
  amoeboid 
  wander- 
  

   ings 
  and 
  absorbed 
  into 
  its 
  mass, 
  but 
  these 
  particles 
  are 
  soon 
  

   excreted 
  or 
  deposited, 
  and 
  have 
  no 
  permanent 
  influence. 
  

  

  To 
  cite 
  a 
  few 
  of 
  the 
  familiar 
  and 
  better-known 
  species 
  ow 
  

   of 
  many 
  which 
  could 
  be 
  given: 
  Fuligo 
  varians 
  always 
  O' 
  

   velops 
  from 
  a 
  rich 
  yellow 
  plasmodium, 
  Dictydium 
  cernun^ 
  

   from 
  a 
  purple-black, 
  Leocarpus 
  fragilis 
  from 
  a 
  reddish 
  oran^^. 
  

   Chondrioderma 
  floriforme 
  from 
  a 
  gray 
  or 
  drab, 
  the 
  Arc)' 
  ^^' 
  

   and 
  many 
  others 
  from 
  an 
  uncolored 
  cr 
  white 
  plasmodium, 
  a 
  • 
  

   so 
  on 
  without 
  any 
  exception 
  that 
  I 
  have 
  noted. 
  ^ 
  .^ 
  

  

  The 
  question 
  of 
  the 
  constancv 
  of 
  the 
  color 
  changes 
  i 
  

   stage 
  following 
  the 
  plasmodial, 
  that 
  of 
  the 
  differentiation' 
  

   development 
  of 
  sporangia, 
  is 
  more 
  difficult 
  of 
  deterrninai 
  

   because 
  it 
  is 
  a 
  progressive 
  stage, 
  one 
  of 
  variable 
  dura 
  j 
  

   and 
  one 
  susceptible 
  to 
  external 
  influences. 
  Nevertlieie 
  - 
  _ 
  

   believe 
  it 
  to 
  be 
  equally 
  true 
  that 
  the 
  color 
  of 
  the 
  corresp 
  

  

  only 
  

  

  mg 
  stages 
  of 
  development 
  of 
  the 
  individual 
  sporang 
  

   Plasmodium 
  to 
  maturity, 
  is 
  always 
  the 
  same, 
  varying 
  

   duration 
  and 
  intensity 
  according 
  to 
  local 
  conditions. 
  |f 
  

   If 
  this 
  view 
  be 
  strengthened 
  by 
  further 
  observatw 
  -^ 
  

   can 
  not 
  be 
  doubted 
  that 
  a 
  knowledge 
  of 
  the 
  color 
  ano 
  ^^^ 
  

   acter 
  of 
  the 
  plasmodium, 
  and 
  of 
  the 
  color 
  changes 
  i 
  

   transitional 
  period 
  from 
  the 
  plasmodic 
  to 
  the 
  mature 
  sj^ 
  

   ot 
  the 
  Myxomycetes, 
  is 
  of 
  diagnostic 
  value, 
  and 
  ^^1^. 
  ^is 
  

   certain 
  conditions, 
  be 
  essential 
  to 
  the 
  correct 
  determm 
  

   ot 
  species 
  and 
  their 
  relations 
  to 
  each 
  other. 
  

  

  