Abo.  Jour.  Pharm.  \ 
March,  1896.  J 
Rhus  Toxicodendron. 
A  SUBSTITUTION  FOR  RHUS  TOXICODENDRON.^ 
By  J.  L.  D.  Morison. 
Contribution  from  the  Botanical  Laboratory  of  the  Philadelphia  College  of 
Pharmacy. 
The  leaves  of  the  common  Virginia  creeper,  Ampelopsis  quinque- 
folia,  Mich.,  are  sometimes  substituted  for  those  of  the  official  Rhus 
toxicodendron. 
This  observation  was  recently  confirmed  in  the  examination  of  a 
quantity  of  the  drug  which  was  purchased  from  one  of  the  most  re- 
liable wholesale  houses ;  and  this  fact  emphasizes  the  necessity  of 
making  a  careful  examination  of  all  drugs  of  this  class  for  the  pur- 
pose of  establishing  their  identity,  judging  of  their  quality,  or  de- 
tecting adulterations  and  substitutions. 
A  fraud  of  this  nature  may  be  easily  detected  by  soaking  up  a 
sample  of  the  leaves  in  water  and  carefully  examining  them.  Those 
of  the  poison  ivy  are  pinnately  compound  with  three  leaflets,  while 
those  of  the  Virginia  creeper  are  palmately  compound  with  five 
leaflets.  The  individual  leaflets  of  the  two  plants  differ  also  in 
form.  The  terminal  leaflet  of  the  poison  ivy  is  long-petiolate, 
ovate  or  oval  in  general  outline,  with  an  acuminate  apex,  a  some- 
what wedge-shaped  base,  and  a  nearly  entire  margin ;  the  lateral 
leaflets  are  nearly  sessile,  obliquely  ovate,  pointed,  unequal  at  the 
base,  with  a  variously  notched  or  toothed  margin,  and  have  short 
petioles  of  nearly  equal  length. 
When  collecting  this  drug,  the  two  plants  may  be  easily  distin- 
guished. Both  have  the  climbing  habit,  the  poison  ivy  being  pro- 
vided with  numerous  adventitious  roots  that  project  from  the  sides 
of  the  stem,  while  the  Virginia  creeper  produces  disk-bearing  ten- 
drils opposite  the  leaves.  The  flowers  of  both  plants  are  small  and 
inconspicuous.  Those  of  the  poison  ivy  are  yellowish-white,  form- 
ing slender  axillary  panicles,  while  those  of  the  Virginia  creeper  are 
greenish  and  occur  in  cymose  clusters. 
There  is  also  a  marked  difference  in  the  appearance  of  the  fruits, 
those  of  the  former  being  yellowish  and  drupaceous,  and  those  of 
the  latter  small,  purplish  berries  covered  with  a  delicate  bloom. 
The  foliage  of  each  is  a  bright  crimson  in  the  autumn,  the  leaves  of 
the  Virginia  creeper,  however,  being  browner  and  assuming  a  more 
vivid  hue. 
