﻿iSgO.] 
  BOTANIC 
  AI. 
  GAZETTE 
  • 
  I7I 
  

  

  The 
  action 
  of 
  osmic 
  acid 
  does 
  not 
  seem 
  to 
  sufficiently 
  

   harden 
  the 
  walls 
  and 
  cell-contents 
  of 
  the 
  most 
  delicate 
  

   Floridea^ 
  (Callithamnion, 
  Griffithsia, 
  fringing 
  hairs 
  of 
  Spy- 
  

   ridias, 
  Das3'a, 
  etc.) 
  to 
  prevent 
  their 
  shrinking 
  even 
  in 
  very 
  

   dilute 
  glycerine, 
  but 
  no 
  one 
  of 
  many 
  other 
  reagents 
  experi- 
  

   mented 
  with 
  gave 
  much 
  better 
  results. 
  Perhaps 
  some 
  of 
  the 
  

   workers 
  at 
  Wood's 
  IIoll, 
  the 
  present 
  season, 
  can 
  remove 
  the 
  

   difficultv. 
  

  

  Most 
  fungi 
  suffer 
  no 
  change 
  in 
  dilute 
  glycerine, 
  although 
  

   not 
  previously 
  hardened, 
  and 
  they 
  may 
  be 
  well 
  preserved 
  in 
  

   glycerine 
  jellv. 
  Such 
  as 
  are 
  too 
  delicate 
  *to 
  do 
  so 
  otherwise 
  

   pay 
  be 
  enabJed, 
  in 
  most 
  cases, 
  to 
  withstand 
  the 
  distorting 
  

   influence 
  of 
  glycerine 
  by 
  hardening 
  in 
  osmic 
  acid, 
  as 
  de- 
  

   scribed 
  for 
  the 
  alga^. 
  I 
  have 
  not 
  yet 
  succeeded, 
  however, 
  in 
  

   sadsfactorily 
  preserving 
  Saprolegniacea^ 
  in 
  this 
  way, 
  though 
  

   the 
  most 
  delicate 
  Mucorace^e 
  and 
  Hyphomycetes 
  do 
  finely. 
  

  

  In 
  short, 
  it 
  is 
  not 
  too 
  much 
  to 
  say 
  that 
  the 
  way 
  is 
  opened, 
  

   by 
  the 
  process 
  above 
  described, 
  toward 
  the 
  abandonment 
  ot 
  

   fluids 
  and 
  cements 
  and 
  all 
  the 
  bothersome 
  manipuladon 
  con- 
  

   nected 
  with 
  their 
  use, 
  and 
  the 
  substitution 
  of 
  a 
  technique 
  

   simpler 
  in 
  detail 
  and 
  far 
  more 
  satisfactory 
  in 
  results. 
  

   Amherst, 
  Mass. 
  

  

  On 
  the 
  nature 
  of 
  certain 
  plant 
  diseases. 
  

  

  ALEXANDER 
  LIVINGSTON 
  KEAN. 
  

  

  . 
  De 
  Bary 
  in 
  his 
  paper 
  " 
  On 
  some 
  Sclerotinise 
  and 
  sclero- 
  

   tiiim 
  diseases,"! 
  published 
  in 
  1886, 
  was 
  the 
  first 
  to 
  show 
  that 
  

   ^clerotinia 
  (Peziza) 
  sclerotiorum 
  while 
  apparenth' 
  growing 
  as 
  

   a 
  parasite 
  actually 
  grows 
  as 
  a 
  saprophyte, 
  but 
  gives 
  off 
  in 
  

   the 
  process 
  of 
  its 
  growth 
  a 
  ferment 
  which 
  swells 
  the 
  cell- 
  

   J^'alls 
  and 
  kills 
  the 
  tissue 
  of 
  the 
  host, 
  thus 
  preparing 
  the 
  way 
  

   Jpr 
  the 
  fungus. 
  In 
  1888 
  Marshall- 
  Ward 
  described 
  a 
  Botry- 
  

   "s 
  growing 
  upon 
  a 
  Lilium 
  candidum 
  which 
  behaves 
  in 
  the 
  

   same 
  manner.^ 
  De 
  Bary 
  found 
  that 
  liquid 
  obtained 
  from 
  

   ^'egetable 
  tissue 
  infested 
  with 
  Sclerotinia 
  was 
  capable 
  of 
  pro- 
  

   auang 
  the 
  characteristic 
  decomposition 
  of 
  pieces 
  of 
  healthy 
  

   nssue 
  placed 
  in 
  it. 
  Marshall-Ward 
  not 
  only 
  obtained 
  this 
  

   !!!^^^j;^sult^ut 
  also 
  observed 
  under 
  the 
  microscope 
  drops 
  of 
  

  

  ^^BotZeit. 
  1886, 
  nos.22.23. 
  

   ' 
  °"*'^ 
  of 
  Botany, 
  Nov., 
  1888. 
  Vol. 
  ii, 
  no. 
  vii. 
  

  

  