Si8 
Poison  Sumac. 
{ 
Am.  Jour.  Pharm. 
November,  1907. 
I. 
0*5047  gramme  gave  5*6  c.c.  N  at  260  C.  and  736  mm. 
II. 
o'SSQ1  gramme  gave  5-9  c.c.  N  at  210  C.  and  746  mm. 
I. 
Per  Cent 
Per  Cent 
8-249 
71-363 
1*119 
EI. 
Mean. 
Per  Cent 
Hydrogen 
Carbon  . 
Nitrogen 
8*342 
71*787 
1*084 
8*296 
7i'575 
I*IOI 
The  fact  that  all  of  the  portions  of  resin  obtained  by  fractional 
precipitation  with  lead  acetate  were  poisonous,  and  that  repeated  pre- 
cipitation and  separation  destroyed  the  poisonous  properties,  indicates 
that  the  benzin-soluble  substance  is  not  a  compound,  but  that 
the  apparently  different  substances  obtained  are  the  result  of  oxida- 
tion. This  is  supported  by  the  fact  that  the  final  lead  compound, 
like  the  ether-insoluble  substance,  is  not  poisonous.  The  small  portion 
of  lead-free  oily  substance  indicates  that  a  portion  of  the  resin  was 
occluded  by  the  lead  precipitate,  thus  preventing  it  from  coming  in 
contact  with  sufficient  lead  acetate  to  precipitate  it.  This  is  sup- 
ported by  the  fact  that  after  separation  it  is  easily  precipitated  by 
the  lead  acetate. 
Several  experiments  were  made  in  order  to  compare  the  latex  of 
poison  ivy  with  that  from  poison  sumac.  The  juice  was  collected 
from  the  ivy  stems  by  a  method  analagous  to  that  used  for  sumac. 
It  occurs  in  ivy  far  less  abundantly  than  in  sumac,  hence  its  collec- 
tion is  much  more  tedious.  In  color  and  consistency  ivy  lac 
resembles  sumac  lac  very  closely,  but  it  is  devoid  of  the  peculiar 
sweetish  odor  of  the  latter.  Qualitative  tests,  showed  that  it  con- 
tains a  brownish-red,  poisonous  resin  soluble  in  alcohol,  a  non-poi- 
sonous gum-enzyme  insoluble  in  alcohol,  but  soluble  in  water,  and  a 
third  substance  insoluble  in  either  of  these  solvents. 
Each  of  these  substances  possesses  properties  very  similar  to  the 
corresponding  substance  in  the  latex  of  the  sumac.  The  resin  is 
apparently  as  venomous  as  its  analogue  in  the  sumac,  but  the  gum- 
enzyme  acts  somewhat  more  slowly  toward  tincture  of  guaiac  than 
does  the  sumac  gum.  No  quantitative  tests  were  made  owing  to 
lack  of  material,  yet  we  believe  that  further  work  will  show  the  pro- 
portions of  the  several  ingredients  of  the  two  juices  to  be  very 
similar. 
