2(50  A?inual  Report  for  1904  of  the  Consulting  Botanist. 
sold  for  that  purpose.”  Whether  charlock  would  be  a paying  crop 
for  this  country  cannot  be  stated,  but  it  may  be  worth  trying 
to  find  some  use  for  this  noxious  plant,  the  seeds  being  plenti- 
fully developed,  and  the  plants  requiring  little  or  no  cultivation. 
Diseases  op  Plants. 
Diseases  were  investigated  on  the  following  plants  : — 
Cereals. — Oats  came  from  Salop  with  Helminthosporium 
gramineam  Eriks.  An  illustrated  description  of  this  fungus 
and  the  means  of  dealing  with  it  were  given  in  my  Report  for 
the  year  1900.  Barley  was  received  from  Yorkshire  with 
Ergsiphe  graminis  D.C.  This  fungus  very  frequently  attacks 
cereals  and  grasses,  and  has  repeatedly  done  serious  mischief. 
It  covers  the  leaves  with  a fine  mould  and  penetrates  the  tissues, 
especially  the  younger  blades.  The  leaves  become  yellow  and 
the  plants  die.  It  is  usually  observed  on  patches  of  dying 
plants  on  the  field,  and  it  should  be  combated  as  soon  as  these 
are  noticed  by  removing  the  plants  and  burning  them  and  by 
spraying  the  neighbouring  plants  with  Bordeaux  mixture. 
Clovers  and  grasses. — Red  clover  and  suckling  clover  were 
received  from  Bedfordshire  and  Norfolk  attacked  by  Ergsiphe 
Martii  Lev.  Red  clover  was  received  from  Hertfordshire 
with  Pseudopeziza  TrifoUi  Fuckel,  and  suckling  clover  from 
Norfolk  with  Uromgces  TrifoUi  Lev. 
Erysqdie  Martii  Lev.  (see  Fig.  1,  N to  R,  page  262)  attacks 
clovers  in  the  same  manner  as  the  species  found  on  grass 
that  has  just  been  referred  to.  It  becomes  serious  only  in  a 
severe  attack  ; it  should  be  dealt  with  as  the  Ergsiphe  on  grass. 
Pseudopeziza  TrifoUi  Fuckel  (see  Fig.  1,  P to  K,  page  262)  is 
found  on  lucerne  and  clovers.  The  leaves  of  the  diseased  plants 
show  small  dark-brown  spots  of  decaying  tissue,  in  the  middle 
of  which  a minute  receptacle  is  situated,  the  fruiting  body  of  the 
fungus  which  is  filled  with  very  minute  sacs  or  asci  containing 
eight  microscopic  spores.  These  are  shed  when  ripe  and  are 
capable  of  infecting  the  leaves  of  healthy  plants.  The  disease 
is  not  very  serious  and  can  be  kept  in  check  by  the  frequent 
cutting  of  the  crop.  It  generally  occui'S  on  stray  plants  on  the 
field  in  the  late  autumn.  To  prevent  the  carrying  of  the  fungus 
over  to  the  next  year  dry  refuse  should  be  spread  over  the 
attacked  parts  of  the  field,  which  being  set  on  fire  consumes  the 
infested  leaves. 
Uromgces  TrifoUi  Hedw.  attacks  the  species  of  Tri folium 
and  other  leguminous  plants  and  forms  dark  reddish-brown 
patches  of  uredospores,  making  the  leaves  appear  as  if  covered 
with  rust.  The  spots  are  very  minute,  but  can  readily  be  seen 
with  the  naked  eye,  as  they  appear  in  large  numbers,  and 
often  cover  the  whole  upper  and  under  surface  of  the  leaves. 
