Report  on  Wheat-Mildew. 
637 
known  to  the  ancient  Egyptians.*  The  Romans  offered  sacrifices 
to  propitiate  their  deity  Robigus,  and  avert  the  disease.  In 
the  ‘Annals  of  Agriculture’  will  be  found  a long  account  of  a 
visitation  which  destroyed  the  crops  in  Sicily  in  1804.f  In 
France,  the  aid  of  the  Law  Courts  has  within  the  last  few  years 
been  invoked  to  obtain  the  removal  of  a barberry  hedge  which  was 
credited  with  having  produced  extensive  mildew  in  the  neighbour- 
ing crops.  In  the  New  World  we  find  the  State  of  Massachusetts, 
as  long  ago  as  1755,  making  a provincial  law  for  the  complete 
extirpation  of  barberry  bushes,  because  it  had  been  found  that 
the  blasting  of  wheat  and  other  English  grain  was  occasioned 
by  them  and  at  the  present  moment  the  wheat-growers  of 
Australia  are  anxiously  inquiring  into  the  origin  and  nature  of 
the  disease. 
Considering  the  wide  distribution  of  mildew,  and  the  fearful 
destruction  which  so  frequently  results  from  it,  it  is  not 
surprising  that  it  has  long  been  the  subject  of  inquiry  by 
scientific  men.  The  attention  of  these  seems,  however,  to  have 
been  almost  entirely  devoted  to  the  biology  of  the  parasitic 
fungus  ( Puccinia  graminis),  which  causes  the  malady.  Im- 
portant as  this  branch  of  the  subject  is,  and  much  as  we  owe  to 
the  botanists  and  mycologists  who  have  pursued  their  investi- 
! gations  so  diligently,  I venture  to  suggest  that  further  inquiry 
in  other  directions  is  desirable  ; and  since  it  seems  to  be 
admitted  that  the  study  of  the  life-history  of  this  mischievous 
fungus  has  suggested  no  effective  means  of  preventing  or 
mitigating  the  disease,  it  is  worth  while  to  ask  whether  the 
observation  and  experience  of  practical  farmers  cannot  furnish 
some  information  which  may  enable  the  chemist  or  the  physicist 
to  assist  them  in  lessening  the  damages  to  which  they  are  now 
liable. 
Physicians,  when  they  have  to  study  disorders  which  affect 
mankind,  or  the  live-stock  of  the  farm,  do  not  content  them- 
selves with  a diagnosis  of  the  disease  ; they  proceed  to  ascertain 
what  are  the  conditions  under  which  the  disease  is  generated, 
propagated,  or  malignantly  developed  ; and  they  inquire  whether 
any  habits  of  life,  any  inherited  predisposition,  any  accidental 
surrounding,  either  spread  the  disease  or  make  it  more  malignant 
in  its  character.  YVhy  should  not  the  same  system  be  followed 
in  the  case  of  plant-diseases  ? 
I have  implied  in  what  I have  said  previously  that  the 
observation  and  experience  of  farmers  may  give  a clue  to 
* In  Wicliff’s  Bible,  the  seven  years  of  scarcity  which  Joseph  foretold  to 
Pharaoh  were  attributed  to  Blildew. 
t Vol.  xliv.  p.  324. 
j A copy  of  this  law  will  be  found  at  p.  692. 
