﻿56 
  Thirtieth 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  Cercospora 
  Chenopodii 
  Fckl. 
  

   Living 
  leaves 
  of 
  Chenopodium 
  album. 
  West 
  Albany. 
  July. 
  

  

  Peronospora 
  alta 
  Fckl. 
  

  

  Living 
  leaves 
  of 
  plantain, 
  Plantago 
  major. 
  Albany. 
  July. 
  

   This 
  is 
  sometimes 
  regarded 
  as 
  a 
  form 
  of 
  P. 
  effusa. 
  

  

  Peronospora 
  ixfestans 
  Be 
  By. 
  

  

  Living 
  leaves 
  of 
  potato 
  vines. 
  Adirondack. 
  August. 
  

  

  This 
  fungus, 
  for 
  a 
  long 
  time 
  considered 
  the 
  cause 
  of 
  the 
  

   potato 
  disease, 
  has, 
  until 
  recently, 
  baffled 
  all 
  efforts 
  to 
  trace 
  

   its 
  life-history. 
  But 
  at 
  last 
  Mr. 
  W. 
  G-. 
  Smith, 
  an 
  earnest 
  

   botanist, 
  a 
  most 
  careful 
  observer 
  and 
  skillful 
  experimenter, 
  

   has 
  succeeded 
  in 
  tracing 
  this 
  history 
  through 
  the 
  yearly 
  cycle. 
  

   He 
  has 
  found 
  and 
  kept 
  alive 
  through 
  the 
  winter, 
  the 
  hiber- 
  

   nating 
  or 
  resting 
  spores 
  of 
  the 
  fungus 
  and 
  caused 
  these 
  to 
  

   reproduce 
  the 
  pestilent 
  potato 
  fungus. 
  His 
  discovery 
  is 
  so 
  

   important 
  that 
  I 
  cannot 
  do 
  better 
  than 
  to 
  quote 
  his 
  concluding 
  

   remarks 
  on 
  the 
  subject, 
  a 
  full 
  account 
  of 
  which, 
  is 
  given 
  in 
  the 
  

   Gardeners' 
  Chronicle: 
  

  

  "For 
  more 
  than 
  thirty 
  years 
  our 
  potato 
  crops 
  have 
  been 
  

   systematically 
  destroyed 
  by 
  two 
  virulent 
  fungi, 
  viz., 
  Peronos- 
  

   pora 
  infestans 
  and 
  Fusisporium 
  Solani 
  ; 
  these 
  two 
  parasites 
  

   almost 
  invariably 
  work 
  in 
  company 
  with 
  each 
  other, 
  they 
  

   suddenly 
  appear 
  for 
  a 
  few 
  weeks, 
  destroy 
  our 
  crops 
  and 
  vanish 
  

   for 
  ten 
  or 
  twelve 
  months 
  then 
  reappear 
  and 
  repeat 
  the 
  work 
  of 
  

   destruction. 
  I 
  claim 
  for 
  my 
  work 
  that 
  it 
  is 
  new, 
  and 
  that 
  it 
  

   has 
  proved 
  how 
  both 
  these 
  fungi 
  hide 
  and 
  sleep 
  through 
  eleven 
  

   months 
  of 
  the 
  year. 
  As 
  I 
  have 
  kept 
  the 
  restiDg-spores 
  of 
  both 
  

   parasites 
  alive 
  artificially 
  in 
  decayed 
  potato 
  leaves 
  in 
  water, 
  in 
  

   moist 
  air, 
  and 
  in 
  expressed 
  diluted 
  juice 
  of 
  horse 
  dung, 
  it 
  con- 
  

   clusively 
  proves 
  to 
  me 
  that 
  the 
  resting-spores 
  hibernate 
  natur- 
  

   ally 
  in 
  the 
  same 
  manner. 
  The 
  seat 
  of 
  danger 
  from 
  both 
  para- 
  

   sites 
  is 
  clearly 
  in 
  dung 
  heaps, 
  ditch 
  sides 
  and 
  decaying 
  potato 
  

   plants. 
  

  

  "Any 
  method 
  of 
  destroying 
  the 
  resting-spores 
  of 
  these 
  pests, 
  

   or 
  of 
  warding 
  off 
  or 
  mitigating 
  their 
  attacks, 
  obviously 
  depends 
  

   in 
  a 
  great 
  measure 
  upon 
  a 
  full 
  knowledge 
  of 
  their 
  life-history. 
  

   That 
  life-history 
  I 
  have 
  endeavored, 
  to 
  the 
  best 
  of 
  my 
  ability, 
  

   to 
  watch 
  and 
  describe 
  for 
  the 
  Gardeners' 
  Chronicle, 
  and 
  I 
  am 
  

   content 
  to 
  let 
  the 
  observations 
  stand 
  on 
  their 
  own 
  merits. 
  

   Sensibly 
  conducted 
  and 
  extensive 
  field 
  experiments 
  might 
  

   probably 
  teach 
  some 
  valuable 
  lessons, 
  but 
  it 
  is 
  difficult, 
  if 
  not 
  

   impossible, 
  for 
  any 
  single 
  individual, 
  whether 
  farmer 
  or 
  botan- 
  

   ist, 
  to 
  institute 
  and 
  carry 
  out 
  such 
  experiments/" 
  

  

  J 
  5 
  

  

  Vertictllium 
  pulvereum 
  P. 
  & 
  C. 
  n. 
  sp. 
  

  

  Effused, 
  pulverent, 
  dark 
  or 
  snuff-brown 
  ; 
  flocci 
  colored, 
  the 
  

   lower 
  branches 
  alternate, 
  the 
  upper 
  opposite 
  or 
  verticillate, 
  

  

  