Am  AJug.?i8«oarm'}  Germination  of  Gr amine cz.  419 
of  the  cane-sugar  which  germinated  grain  contains  is  the  tissues  of 
the  embryo  itself. 
In  the  discussion  following  the  reading  of  this  interesting  paper, 
Mr.  Thiselton  Dyer  said  that  botanists  had  already  made  some  pro- 
gress in  localizing  enzymes;  thus  Professor  Marshall  Ward  had 
shown  that  the  enzyme  which  effects  the  liberation  of  the  coloring 
matter  from  the  glucoside  in  Persian  berries  is  located  in  the  raphe; 
and  it  had  long  been  known  that  emulsin  was  not  distributed 
throughout  the  bitter  almond.  After  referring  to  the  distinction 
between  animals  and  plants,  he  said  that  the  plant  was  similar  to 
the  seed,  the  bud  corresponding  to  the  embryo,  and  the  woody 
shoot  to  the  endosperm.  Baranezky  had  shown  that  a  diastase  is 
omnipresent  in  plants,  and  there  could  be  little  doubt  that  it  would, 
be  found  that  an  enzyme  capable  of  attacking  cellulose  was- 
equally  so. 
Professor  Marshall  Ward  pointed  out  that  in  the  seeds  of  the 
Gramineae,  Cyperaceae  and  other  families  of  plants  there  is  a  pecu- 
liar layer  of  cells,  from  one  to  three  or  more  deep,  surrounding  the 
starchy  endosperm  and  distinguished  from  the  latter  by  containing 
no  starch  but  relatively  large  quantities  of  proteids ;  this  layer 
belongs  to  the  endosperm,  but  as  the  seed  ripens  the  cells  store 
special  proteids  instead  of  the  starch  grains  which  predominate  in 
the  other  endosperm  cells. 
In  the  oat  there  is  such  a  layer,  one  cell  deep,  and  it  has  been 
shown  that,  during  germination,  the  dissolution  of  the  starch  and  the 
cell-walls  of  the  starch  containing  cells  begins  near  the  surface  of 
this  layer,  which  itself  persists  and  the  cells  of  which  take  up  food 
and  undergo  changes  so  like  those  of  excreting  cells,  that  it  was 
concluded  that  they  excrete  the  diastatic  enzyme.  Haberlandt 
declares  that  when  starch-grains  are  placed  in  contact  with  a  piece 
of  this  layer  kept  moist  and  at  proper  temperatures,  the  grains 
even  of  the  resistent  potato  starch  are  corroded  as  on  germination  ; 
whereas  control  experiments,  where  all  conditions  are  the  same 
except  the  presence  of  the  cells  of  the  proteid  layer,  showed  no 
such  corrosion. 
The  proof  that  a  cellulose  dissolving  enzyme  exists  in  barley  is 
borne  out  by  various  recent  researches  and  by  Wortmann's 
researches  on  the  behavior  of  bacteria  in  a  mixture  of  starch  and 
proteids.    Wortmann  proved  that  so  long  as  the  bacteria  were  fed 
