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■>4  MONTHLY.  [> 
Vol.  XV.]  COLOMBO,  JAN,  ist,  i8g6,  [No.  7. 
THE  LATENT  VITALITY  OF  SEEDS. 
CASIMIR  cle  Candolle  has  lately 
published  an  interesting  paper 
entitled  La  Vie  J^atente  tks 
O'yaiiii  'i  (Archives  des  Sc.  Rhys. 
ct  Nat. ; iiibl.  Univers.,  1893)> 
in  which  he  comes  to  the  con" 
elusion  that  if  the  external 
conditions  necessary  for  the 
vital  activities  of  seeds  be  absent  for  a long  time 
they  may  be  totally  arrested,  but  yet  the  seeds  may 
be  alive  and  re-enter  an  active  course  of  existence 
after,  perhaps,  an  indefinite  period.  His  experiments 
were  conducted  in  a cold  room  of  a meat  refrigerator’ 
having  made  a preliminary  one  as  follows;  Ihree 
lots  of  Peas  and  Haricot  Beans  were  placed  (1)  in 
free  air ; (2)  in  a tube  of  air,  but  sealed  ; (if)  in  pure 
carbonic  acid.  After  two  years  (1}  had  increased  in, 
weight,  and  nearly  all  germinated  ; i2)  had  lost  weight 
while  a silialler  proportion  germinated  ; air  now  con- 
taining 11-1  per  cent,  of  oxygen,  and  f’.-H  per  cent,  of 
carbonic  acid ; (;!)  none  came  up.  He  asks  the 
question  whether  the  enfeebled  vital  activities  had 
ceased  before  the  end  of  the  experiment,  so  that 
respiration  and  assimilation  had  completely  stopped ; 
if  so,  the  protoplasm  must  become  quite  iuert.  He 
believes  that  to  be  the  case.  He  now  experimented 
with  an  intensely  cold  temperature,  having  previously 
determined  that  Peas,  Haricots,  and  Fennel  seed, 
would  germinate  after  an  exposure  of  four  days  to 
a temperature  of  1-180  R.  Ue  wrapped  up  some  Wheat, 
Oats,  seeds  of  Fennel,  of  the  Sensitive  plant,  and 
of  Lobelia  Erinus  in  tin  foil.  All  were  well  packed 
in  a cylindrical  iron  box  of  3A  cubic  feet  capacity . 
the  lid  being  hermetically  sealed.  This  was  placed 
in  an  open  wooden  box  for  protection.  The  whole 
was  subjected  to  an  intermittent  steani  of  intensely 
cold  air  coming  direct  from  the  refugcrator,  from 
May  to  September,  1894,  or  118  days. 
The  cold  air  was  continued  from  eight  to  twenty 
hoius  per  day  ; the  average  time  being  fourteen  hours. 
On  the  greatest  number  of  occasions  (sixty-eight 
times),  the  cold  was  prolonged  for  twenty  hours. 
The  lowest  temperature  reached  was — 63°  F.,  and  the 
highest — 36°  F. 
In  the  intermediate  periods  the  warming  was  very 
slow,  for  the  temperature  scarcely  passed  freezing- 
point  at  the  end  of  two  to  three  hours,  after  stopping 
the  machine.  Conversely,  the  cooMng  of  the  box 
was  very  rapid,  as  it  was  directly  exposed  to  the 
current  of  cold  air. 
M.  De  Candolle  asks  the  question  whether  the 
box  ceuld  check  the  cooling.  As  an  experiment  in 
this  direction,  he  completely  filled  a bo.x  with  corn* 
The  lid,  being  hermetically  sealed,  was  then  pierced 
to  allow  the  bulb  of  a thermometer  to  pass  through 
it,  and  the  hole  was  then  plugged  with  cotton- wool. 
He  then  observed  the  thermometer  outside  a window . 
The  rate  of  cooling  varied  much  according  to  the 
initial  temperatures,  and  in  proportion  as  the  exterior 
air  was  calm  or  agitated.  Thus,  in  a strong  north- 
east wind,  the  temperature  of  the  room  being  18° 
Fahr.,  and  17‘5°  Fahr.  outside,  it  took  twenty-six 
minutes  to  ascend  to  21°  Fahr.  On  a calm  day 
when  it  was  5.3-0°  Fahr.  in  the  room  and  at  freezing 
point  ontside,  it  took  one  hour  and  eight  minutes  to 
descend  to  freezing  point. 
But,  as  M.  De  Candolle  observes,  this  experiment 
does  not  bear  much,  if  any,  analogy  to  the  cooling 
by  the  air  from  a refrigerator,  for  the  box  was  placed 
in  the  direct  current  from  it.  Moreover  the  seeds 
were  surrounded  by  a metallic  paper,  greatly  facilitat- 
ing the  conductibility  of  the  box.  He  thinks,  there- 
fore, that  not  more  than  a quarter  of  an  hour  would 
be  required  to  put  the  temperature  of  the  box  in 
equilibrium  with  that  of  the  cold  air.  On  taking  out 
the  seeds,  they  were  at  once  sown.  Nearly  all  the 
Wheat,  some  of  the  Oats,  and  some  Fennel  seeds 
quickly  appeared.  Of  sixty-six  seeds  of  the  Sensitive 
plant,  thirteen  only  came  up ; while  of  numerous 
Lobelia  seeds,  only  ten  germinated 
The  failure  of  the  seeds  of  the  Sensitive  plant  was 
not  solely  due  to  the  cold,  as  many  failed  to  "ger- 
minate, while  many  Lobelia  plants  grew  in  a control 
experiment.  The  conclusion  the  author  arrived  at 
was  that  life,  as  expressed  by  vital  functions,  was 
completely  arrested  for  a time ; the  protoplasm  was 
inert,  and  could  not  either  respire  or  assimilate* 
