74 
Hyoscyamus  Niger. 
[Am.  Jour.  Pharm. 
^    February,  1919. 
poisons.  Similarly,  Borneman  (i)  stated  that  these  plants  should 
be  sprayed  about  every  day,  as  the  potato  bugs  would  devour  them 
in  one  day.  Farwell  (3)  concluded  that  the  lack  of  success  in  com- 
mercial culture  of  hyoscyamus  is  the  large  cost  in  keeping  the  plant 
free  from  bugs. 
Since  it  was  difficult  to  keep  Hyoscyamus  niger  free  from  chew- 
ing insects,  a  series  of  experiments  were  made  to  ascertain  what 
spray  mixtures  could  be  employed  that  would  keep  the  insects  off 
the  plants,  and  still  not  be  injurious  to  the  plant  tissues.  As  a  pre- 
liminary experiment,  15  large  Hyoscyamus  niger  plants  were 
selected.  These,  as  yet,  had  not  been  attacked  by  any  insects. 
Three  plants  were  sprayed  with  arsenate  of  lead  (5  lbs.  100  gal.)  ; 
three,  with  Paris  green  (1  lb.  100  gal.)  ;  three  were  dusted  with 
flowers  of  sulphur,  and  six  were  kept  as  controls,  or  untreated.  The 
plants  were  sprayed  on  May  22,  31,  and  again  on  June  6,  and  the 
effects  of  the  insects  was  carefully  watched.  The  results  are  pre- 
sented in  the  following  table : 
TABLE  V. 
Showing  the  Control  of  the  Plants  of  Hyoscyamus  niger  Against  the 
Attack  of  Insects. 
Plants 
No.  Treatment.  Results. 
1  No  treatment.  Almost  entirely  destroyed. 
2  Entirely  destroyed. 
3  Entirely  destroyed. 
4  Arsenate  of  lead!  Plants  fine,  few  small  holes  in  leaves. 
5  Plants  fine,  few  small  holes  in  leaves. 
6  Plants  fine,  few  small  holes  in  leaves. 
7  Paris  green.  Plants  destroyed  by  spray. 
8  Plants  destroyed  by  spray. 
9  Plants  destroyed  by  spray. 
10  Sulphur  Little  injury,  lower  leaves  destroyed. 
11  Little  injury,  lower  leaves  destroyed. 
12  Little  injury,  lower  leaves  destroyed. 
13  No  treatment.  Almost  entirely  destroyed. 
14  Almost  entirely  destroyed. 
15  Entirely  destroyed. 
From  the  foregoing  results,  it  is  very  apparent  that  hyoscyamus 
plants  must  be  sprayed  in  order  to  control  insects,  as  in  every  case 
the  control  plants  were  either  partially  or  entirely  destroyed. 
Arsenate  of  lead  was  very  effective  in  controlling  the  insects,  and 
