THE  AMEEICAN 
JOURNAL  OF  PHARMACY 
NOVEMBER,,i<?io  , 
 |U  % 
RHUS  MICHAUXII— A  NON-PO^NOUS  .^^VNt  * , 
By  L.  E.  Warren.  N$*>.^ 
Numerous  plants  are  known  which  occasionally  cause  inflam- 
matory conditions  when  brought  in  contact  with  the  human  skin. 
While  the  majority  of  these  are  but  slightly  poisonous  to  most 
individuals  and  some,  like  the  ladyslipper  1  and  the  Indian  pipe,2 
are  irritant  only  to  the  most  sensitive  skins  there  are  a  few  which  so 
generally  cause  untoward  symptoms  that  they  are  ordinarily  con- 
sidered venomous.  Although  representatives  of  more  than  forty 
families  of  plants  have  been  accredited  with  poisonous  properties  of 
this  nature,3  the  most  of  those  commonly  designated  as  poisonous 
belong  to  a  single  order,  the  Anacardiaceae  (Cashew  family).  Rep- 
resentatives of  this  family  occur  in  great  numbers  in  the  Tropics  and 
are  found  less  abundantly  in  all  of  the  temperate  regions  of  the 
globe.  Many  genera  in  the  Cashew  family  contain  poisonous  species, 
the  genus  Rhus  probably  claiming  as  many  as  any  other. 
About  1 20  species  of  Rhus  are  known,4  but  of  these  only  about 
20  are  thought  to  be  poisonous.  AH  of  the  venomous  species 
contain  a  viscid,  pale  cream-colored,  emulsion-like  juice,  which 
*  We  are  indebted  to  Prof.  William  Trelease,  Director  of  the  Missouri 
Botanical  Garden,  for  the  use  of  the  electrotype  showing  the  habit  of  Rhus 
Michauxii,  and  which  was  used  to  illustrate  an  article  in  Volume  XX,  Report 
of  the  Missouri  Botanical  Garden. — Editor. 
'Babcock,  H.  H. :  The  Pharmacist,  8,  1  (1875);  also  A.  Ph.  A.  Proc, 
23,  137  (1875).  MacDougal,  D.  T. :  Gard.  &  For.,  9,  40  (1896). 
2  Young,  A.  H.:  Bot.  Gaz.,  3,  37  (1878). 
3  White,  J.  C. :   "Dermatitis  Venenata,"  29  (1887). 
4Britton  and  Brown:   111.  Flor.,  2,  386  (1897). 
(499) 
