484 
The  Germination  of  Belladonna  Seed. 
Am.  Jour.  Pharm. 
[  November,  1914. 
Methods  of  Study. 
In  the  experiments  which  were  conducted  in  the  greenhouse, 
the  seeds  were  planted  in  pots  of  convenient  size  containing  good 
loose  soil.  The  surface  was  marked  off  in  rows  about  three-quarters 
of  an  inch  apart,  and  the  same  number  of  seeds  were  placed  in  each 
pot  for  each  experiment.  The  seeds  were  planted  about  a  quarter  of 
an  inch  deep,  and  a  thin  layer  of  sand  was  scattered  over  the  surface. 
Suitable  conditions  of  moisture  and  temperature  were  constantly 
maintained. 
Effects  of  Freezing  on  the  Germination. 
Experience  has  shown  that  seed  sown  late  in  fall  usually  ger- 
minates quickly  in  spring,  while  spring-sown  seed  is  much  slower  in 
germinating.  This  fact  pointed  to  the  possibility  that  frost  might 
have  a  favorable  effect  in  hastening  germination.  As  a  definite  test 
a  small  lot  of  seed  was  divided  into  two  parts,  one  to  serve  as  a 
check  and  the  other  half  to  be  frozen.  The  freezing  was  accom- 
plished by  placing  the  seeds  in  a  test-tube  with  sufficient  water  to 
cause  them  to  cling  together,  and  then  subjecting  the  tube  to  a  tem- 
perature of  — 12°  C.  for  five  hours.  Forty-eight  seeds  from  this 
frozen  lot  were  sown  in  one  side  of  a  io-inch  pot,  while  the  same 
number  of  seeds  from  the  untreated  lot  were  sown  in  the  other  half 
as  a  check.  These  seeds  were  sown  on  April  13th.  The  following 
table  gives  the  number  and  per  cent,  germinated  at  various  intervals : 
Table  I. 
Germination  of  Frozen  and  Unfrozen  Seeds  Sown  on  April  ijth. 
Germination 
Description 
Number 
Per  cent. 
May 
,  May 
May 
May 
May 
May 
May 
May 
8 
IS 
22 
29 
8 
IS 
22 
29 
Frozen  
22 
24 
25 
26 
46 
50 
52 
54-2 
Check  (unfrozen) 
5 
IO 
12 
13 
IO.4 
20.8 
27 
29,2 
Figure  1  shows  graphically  the  percentage  of  total  germination 
at  each  observation.  The  effect  of  freezing  is  immediately  apparent, 
and  the  possibility  suggests  itself  of  hastening  the  germination  of 
the  seeds  in  greenhouse  work  by  subjecting  them  either  to  cold 
weather  or  some  such  treatment  as  described  above.    It  also  empha- 
