﻿I 
  Sep-] 
  BOTANICAL 
  GAZETTE. 
  

  

  297 
  

  

  of 
  collodion 
  for 
  infiltrating 
  we 
  are 
  indebted 
  to 
  Duval 
  who 
  

   first 
  published 
  his 
  results 
  in 
  the 
  Jour, 
  de 
  V 
  Anat., 
  i8^g, 
  p. 
  

   1S5. 
  A 
  little 
  later 
  Merkel 
  and 
  Schiefferdecker 
  suggested 
  

   the 
  use 
  of 
  celloidin 
  which 
  is 
  merely 
  a 
  patent 
  collodion. 
  

   This 
  appeared 
  in 
  the 
  Archiv.f. 
  Anat. 
  u. 
  Phys., 
  1882, 
  p. 
  200. 
  

   Some 
  discussion 
  then 
  arose 
  regarding 
  the 
  relative 
  merits 
  of 
  

   each, 
  but 
  it 
  is 
  generally 
  agreed 
  that 
  one 
  has 
  little 
  or 
  no 
  ad- 
  

   vantage 
  over 
  the 
  other. 
  The 
  method 
  as 
  applied 
  to 
  plant 
  

   tissue 
  is 
  a 
  comparatively 
  new 
  one. 
  In 
  1884 
  we 
  find 
  a 
  short 
  

   description 
  of 
  it 
  in 
  Strasburger's 
  Botany 
  and 
  some 
  few 
  modi- 
  

   ncations 
  of 
  h 
  have 
  since 
  been 
  offered. 
  

  

  In 
  the 
  histological 
  laboratories 
  at 
  Cornell 
  University, 
  un- 
  

   cler 
  the 
  direction 
  of 
  Professors 
  S. 
  H. 
  Gage 
  and 
  W. 
  R. 
  Dud- 
  

   ley, 
  I 
  have 
  tried 
  the 
  method 
  with 
  its 
  various 
  modifications 
  on 
  

   many 
  different 
  kinds 
  of 
  plant 
  tissue, 
  and 
  find 
  the 
  following 
  

   operations 
  to 
  be 
  in 
  eveiy 
  particular 
  the 
  best 
  to 
  obtain 
  uni- 
  

   lormly 
  good 
  results 
  : 
  

  

  . 
  The 
  tissue 
  to 
  be 
  treated 
  is 
  first 
  dehydrated 
  and 
  hardened 
  

   in 
  alcohol. 
  For 
  this 
  purpose 
  a 
  Schultze's 
  apparatus 
  is 
  of 
  the 
  

   nfst 
  importance 
  : 
  in 
  fact 
  I 
  have 
  found 
  some 
  tissues 
  that 
  could 
  

   oe 
  hardened 
  in 
  no 
  other 
  way 
  without 
  shrinking. 
  The 
  results 
  

   JiiJiy 
  warrant 
  the 
  statement 
  that 
  no 
  one 
  engaged 
  in 
  histolog- 
  

   ical 
  botany 
  can 
  afford 
  to 
  be 
  without 
  such 
  an 
  apparatus, 
  

   jyany 
  forms 
  of 
  it 
  have 
  been 
  suggested, 
  but 
  for 
  most 
  plant 
  

   Jissues 
  one 
  which 
  will 
  be 
  found 
  very 
  convenient 
  can 
  be 
  made 
  

   Dy 
  htting 
  into 
  a 
  Whitall-Tatum 
  museum 
  jar 
  a 
  rack 
  in 
  which 
  

   several 
  dehydrating 
  tubes 
  can 
  be 
  supported 
  at 
  any 
  desired 
  

   'evel 
  in 
  the 
  alcohol 
  contained 
  in 
  the 
  iar. 
  In 
  place 
  of 
  tl 
  

  

  parchment 
  diaphragm 
  usually 
  used 
  I 
  recommend 
  the 
  use 
  of 
  

   cnamois 
  skin. 
  With 
  such 
  an 
  apparatus, 
  from 
  12 
  to 
  25 
  hours 
  

   r 
  suthcient 
  for 
  hardening 
  and 
  dehydrating 
  any 
  plant 
  tissue. 
  

   ,?^j'"g 
  the 
  apparatus 
  the 
  tissue 
  should 
  be 
  packed 
  closely 
  in 
  

   "le 
  dehydrating 
  tube, 
  and 
  enough 
  50 
  % 
  alcohol 
  added 
  to 
  just 
  

   cover 
  It. 
  The 
  tube 
  is 
  then 
  sunk 
  in 
  the 
  95 
  fo 
  alcohol 
  in 
  the 
  

   0-^1 
  ^^'^ 
  ^^o 
  liquids 
  are 
  at 
  a 
  level. 
  The 
  strength 
  of 
  the 
  

   tim'^' 
  °^°^ 
  ^^^ 
  be 
  kept 
  up 
  by 
  adding 
  to 
  it, 
  from 
  time 
  to 
  

  

  "le, 
  some 
  calcium 
  chloride. 
  This 
  will 
  not 
  in 
  any 
  way 
  in- 
  

   {" 
  ? 
  1 
  ^ 
  alcohol. 
  The 
  tissue 
  is 
  taken 
  from 
  the 
  95 
  fc 
  alcohol 
  

   i 
  " 
  P'^^ed 
  in 
  a 
  2 
  % 
  solution 
  of 
  collodion, 
  made 
  by 
  dissolv- 
  

   anH 
  P"^""^ 
  of 
  gun 
  cotton 
  in 
  100 
  cc. 
  of 
  equal 
  parts 
  of 
  ether 
  

   hn, 
  ^'^°'^<^1- 
  In 
  this 
  it 
  is 
  allowed 
  to 
  remain 
  from 
  12 
  to_ 
  24 
  

   enm 
  'i 
  .P^^^^ng 
  on 
  the 
  nature 
  of 
  the 
  tissue, 
  24 
  hours 
  being 
  

   solm^ 
  ^01" 
  the 
  very 
  firmest. 
  It 
  is 
  then 
  transferred 
  to 
  a 
  5 
  % 
  

  

  'ution, 
  or 
  the 
  2 
  % 
  solution 
  is 
  allowed 
  to 
  evaporate 
  until 
  it 
  

  

  °^ 
  the 
  consistency 
  of 
  the 
  5 
  % 
  solution. 
  The 
  former 
  method 
  

  

  