Report  on  Wheat-Mildew. 
639 
sent  what  one  would  like  to  know,  and  what  ought  to  be 
systematically  observed  and  noted  in  the  future,  if  we  are  to 
discover  in  what  degree  the  disease  is  encouraged  or  pro- 
moted by  the  surroundings  of  the  crop  and  the  conditions 
under  which  it  is  grown.  I have  to  offer  my  thanks  to  those 
who  did  endeavour  to  assist  me.  An  abstract  of  the  replies 
will  be  found  in  an  Appendix  * to  this  paper.  I have  also 
abstracted  from  the  ‘ Annals  of  Agriculture,’  published  by  the 
Board  of  Agriculture,  some  of  the  replies  which  Arthur  Young 
received  to  his  questions  eighty  years  ago,  when  farmers  were 
still  suffering  from  the  virulent  attack  of  mildew  which  occurred 
in  1804.f 
Before  proceeding  to  notice  these  replies,  I purpose  to  give 
a brief  and  popular  account  of  the  nature  of  the  disease 
known  as  wheat-mildew,  and  in  doing  this  I shall  avail  myself 
of  Mr.  Carruthers’s  paper  on  the  subject  contained  in  last  year’s 
‘ Journal, ’J  and  also  of  a paper  contributed  to  the  ‘Gardener’s 
Chronicle  ’ in  August  1882,  § by  Mr.  C.  B.  Plowright,  of  King’s 
Lynn,  who  is  well  known  as  an  authority  on  British  Fungj, 
and  who  has  given  special  attention  to  this  particular  disease. 
Wheat-mildew  is  caused  by  a parasitic  fungus,  known  as 
Puccinia  graminis,  which  attacks  both  oats  and  barley,  as 
well  as  many  of  the  natural  grasses  of  this  country.  (|  This 
parasite  lives  within  the  cellular  tissue  of  the  plant,  sapping 
its  vitals,  and  converting  to  its  own  use  the  sap  which  should 
nourish  and  mature  the  grain.  The  presence  of  this  fungus  in 
the  infested  host-plant  is  evidenced  only  by  its  fruit  or  repro- 
* App.  II.,  pp.  665-684,  t App.  IV.,  pp.  685-690. 
I ‘ Journal  R.A.S.E.,’  vol.  xviii.  pp.  495-503  : 1882. 
§ ‘-On  Wheat-Mildew  and  its  Connection  with  the  Barberry;”  ‘Gardener's 
Chronicle,’  August  1882. 
||  Mr.  Plowright  gives  the  following 
graminis  has  been  known  to  occur. 
Phleum  pratense. 
Alopecurus  pratensis. 
„ fulvus. 
Phalaris  arundinacea. 
Agrostis  vulgaris. 
„ alba. 
Calamagrostis  epigejos. 
Aira  caespitosa. 
Avena  sativa. 
„ fatua. 
„ pratensis. 
„ flavescens. 
„ elatior. 
Poa  annua. 
„ nemoralis. 
„ pratensis. 
Molenia  cserulea. 
Holcus  lanatus. 
list  of  grasses  upon  which  Puccinia 
Dactylis  glomerata. 
Festuca  gigantea.  v. 
„ spectabilis. 
„ tenella. 
Bromus  mollis. 
,,  tectorum. 
Triticum  vulgare. 
„ repens. 
„ caninum. 
Secale  cereale. 
Lolium  perenne. 
Elymus  arenarius. 
„ glaucifolius. 
Hordeum  vulgare. 
,,  syivaticum. 
„ murinum. 
„ distichum. 
