78 
Hyoscyamus  Niger. 
/Am.  Jour.  Pharm. 
<-   February,  19 19. 
The  above  experiment  shows  conclusively  that  the  potato  beetles 
can  live  for  a  long  period  of  time  without  receiving  any  food.  Their 
size  diminishes  gradually  during  their  period  of  fasting,  and  they 
decrease  to  less  than  one  third  of  their  original  size  before  they  die. 
It  shows  that  the  larger  beetles  can  withstand  the  lack  of  food  much 
better  than  the  smaller  ones.  It  also  demonsrates  the  fact  that 
potato  beetles  will  utilize  their  own  kind  as  a  source  of  food  when 
necessity  demands  it. 
Seed  Formation. 
Since  it  was  found  very  difficult  to  secure  seeds  of  Hyoscyamus 
niger  from  the  various  possible  sources,  the  extent  of  seed  forma- 
tion and  selection  were  studied.  To  determine  the  effect  of  the 
stage  of  maturity  of  the  seeds  upon  their  variability,  seeds  were 
collected  from  plants  at  various  periods.  After  they  were  dry, 
germination  tests  were  made  by  the  blotter  method  as  mentioned 
above.  Four  samples  were  considered  in  this  experiment.  Sample 
no.  1  was  collected  on  June  21,  191 8,  and  sample  no.  2,  on  June  25, 
1918.  The  plants  from  which  these  seeds  were  taken  were  large 
and  branching.  The  leaves  and  seed  pods  were  still  green.  Some 
of  the  seeds  in  the  pods  were  white  in  color,  but  most  of  them 
were  beginning  to  turn  brown.  Samples  nos.  9  and  10  were  col- 
lected on  July  24  and  25,  respectively.  These  seeds  were  taken 
when  the  leaves  and  seed  pods  were  quite  dry  and  the  seeds  were 
dark  brown  and  hard  in  consistency.  The  relative  viability  of  these 
four  samples  of  seed  are  shown  in  the  table  below. 
TABLE  VIII. 
Showing  the  Relative  Viability  of  Seeds  of  Hyoscyamus  niger  Collected 
at  Various  Stages  of  Maturity. 
Percentage  of  Germination 
Sample  No. 
Date  of  Collection 
9  Days 
18  Days 
I 
June  21 
I.O* 
4.0 
2 
June  25 
3-0 
6.0 
9 
July  24 
68.0 
73-0 
10 
July  25 
93-0 
95-o 
*  These  results  are  the  average  of  two  determinations. 
The  results  presented  in  Table  VIII  are  very  conclusive  and 
show  that,  in  order  to  secure  viable  seed's  of  Hyoscyamus  niger,  they 
