500 
Rhus  Michauxii. 
f  Am.  Jour.  Pharm. 
\  Xoveinber,  1910. 
contains  the  poisonous  principle  as  its  chief  ingredient.  Through 
an  oxidizing  process  engendered  by  an  enzyme  this  juice  begins  to 
darken  at  once  on  exposure  to  air  and  eventually  becomes  converted 
into  a  black,  lustrous,  exceedingly  durable  varnish  which,  in  Oriental 
countries,  is  much  esteemed.  An  alcoholic  extract  of  the  juice  con- 
tains the  poisonous  principle  and  gives  characteristic  precipitates  or 
colorations  with  alcoholic  solutions  of  certain  metallic  salts. 
In  a  recent  compilation  of  the  poisonous  species  of  Rhus  5  by 
the  author  it  was  noted  that  while  further  exploration  might  increase 
the  number  already  known,  additional  investigation  might  elim- 
inate some  already  classed  with  the  venomous  species.  The  ques- 
tion of  the  poisonous  properties  of  one  of  the  species,  Rhus 
Michauxii,  has  been  under  discussion  for  nearly  a  century. 
Rhus  Michauxii  or  dwarf  sumac,  the  smallest  and  least  common 
of  all  the  sumacs,  is  a  shrub  with  stout,  erect  stems  from  one  to  three 
feet  in  height.  It  is  a  rare  and  little  known  plant,  found  only  in 
limited  areas  in  the  sandy  soils  of  Georgia  and  the  Carolinas.  The 
deciduous,  compound  leaves  are  from  12  to  14  inches  in  length, 
with  from  7  to  13  lanceolate  or  ovate,  very  short  stalked,  coarsely 
serrate,  pubescent  leaflets.  The  flowers  are  very  small  and  incon- 
spicuous, growing  thickly  in  a  dense  panicle  which  is  about  6  inches 
long  by  nearly  3  broad.  The  fruit  is  a  one-seeded,  nearly  globose 
drupe,  about  an  eighth  of  an  inch  in  diameter,  clothed  with  a  close 
pubescence  of  short,  stout,  crimson  hairs. 
Rhus  Michauxii  Sarg.  (R.  pumilum  Michx.)  [Schmaltzia 
Michauxii  (Sarg.)  Small]  was  first  described  by  Andre  Michaux,6 
a  distinguished  French  traveler  and  botanist,  who  visited  this  country 
late  in  the  eighteenth  century.  While  Michaux  has  left  an  accurate 
description  of  the  plant  he  makes  no  mention  7  of  any  venomous 
properties  in  connection  with  it.    This  omission  is  significant,  since 
5  Warren,  L.  E. :  Pharm.  Jour.,  83,  531  (1909). 
6  Michaux,  A.:  Flor.  Bor.  Am.,  1,  182  (1803). 
7  Michaux's  work,  the  "  Flora  Boreali  Americana,"  was  not  published 
until  after  his  death.  Most  of  the  plant  descriptions  were  written  by  the 
editor,  Richard,  and  were  based  upon  specimens  collected  by  Michaux  during 
his  travels  and  supplemented  by  notes  from  his  journal.  Portions  of 
Michaux's  journal,  edited  by  Prof.  C.  S.  Sargent,  were  published  (in  French) 
in  the  proceedings  of  the  American  Philosophical  Society  in  1889.  An  English 
translation  of  this  has  also  appeared  (Thwaites:  Early  West.  Travels,  vol.  3* 
pp.  1-104,  1904). 
