218 
Botany  and  Materia  Me  die  a. 
Am.  Jour.  Pharm. 
April,  1896. 
F.  W.  Cord  describes,  in  Garden  and  Forest, 
Poisoning-  of      experiments  tried  at  the  Agricultural  College, 
Plants.  Lincoln,  Neb.,  in  order  to  decide  the  effects  of 
poisonous  substances  upon  plant  life.  The 
experiments  were  undertaken  in  order  to  practically  test  the  state- 
ments of  physiologists  that  the  roots  of  plants  have  little  or  no 
power  of  selecting  their  food,  and  can  be  poisoned  like  animals. 
The  experiments  were  tried  by  subjecting  corn  and  beans,  previously 
germinated  and  developed  a  few  inches,  to  solutions  of  alcohol, 
corrosive  sublimate,  sulphuric  acid,  extract  of  aconite,  arsenic  and 
strychnine.  From  the  results  the  following  conclusions  are  deduced  : 
(1)  Irritant  poisons,  such  as  arsenic,  corrosive  sublimate  and  sul- 
phuric acid,  kill  plants  in  water  cultures  in  a  very  short  time,  except 
in  -oi  per  cent,  solutions,  and  in  such  solutions  plants  were  less 
vigorous  than  in  city  water. 
(2)  The  neurotic  poisons,  alcohol,  aconite  and  strychnine,  killed 
no  plants,  with  the  exception  of  the  very  strong  solution  of  alcohol 
and  one  plant  treated  with  strychnine. 
(3)  All  the  poisons  used,  except  alcohol,  affected  beans  more 
quickly  and  severely  than  corn.  Alcohol,  on  the  contrary,  affected 
corn  more  than  beans. 
(4)  The  poisons  produced  much  greater  effects  in  water  than  in 
soil  cultures. 
The  strongest  solution  of  aconite  and  strychnine  used  contained 
only  one-tenth  of  1  per  cent.;  hence,  it  is  possible  that  a  stronger 
solution  might  have  a  different  effect;  yet  the  same  strength  of 
arsenic  and  corrosive  sublimate  killed  plants  very  quickly.  The 
results  are  more  striking  when  it  is  remembered  that  from  20  to  40 
times  as  much  arsenic  or  corrosive  sublimate  is  required  to  prove 
fatal  to  animals  as  of  strychnine  sulphate.  The  irritant  or  corrosive 
poisons,  however,  attack  and  decompose  tissue ;  hence,  may  be 
expected  to  injure  plants  as  well  as  animals.  The  neurotic  poisons 
affect  only  the  nerves  of  animals,  and  are,  therefore,  less  likely  to 
injure  plants. 
In  Bulletin  No.  9,  Part  VII,  of  the  Minnesota 
Poisonous  Influence  Botanical   Studies,  Prof.  D.  T.  MacDougal 
of  Various  Species  ,.  -.  .     r        ,        .  . 
of  Cypripedium.    directs  attention  to  the  fact  that  the  leaves 
and  stems  of  Cypripedium  spectabile  and  C. 
pubescens  exert  a  poisonous  influence  on  the  human  skin.  The 
