Am.  Jour.  Pharm.  \ 
November,  1910.  J 
Rhus  Michauxii. 
505 
A  portion  of  the  residue  obtained  by  evaporation  of  the  alcoholic 
extract  of  the  twigs  was  dissolved  as  completely  as  possible  in  a 
small  quantity  of  petroleum  ether,  the  solution  filtered,  and  the 
filtrate  poured  with  stirring  into  a  large  excess  of  petroleum  ether. 
After  standing  twenty-four  hours  the  mixture  was  filtered,  the 
filtrate  allowed  to  evaporate  spontaneously,  and  a  drop  of  the  residue 
tested  upon  the  arm  as  above  described.  These  tests  also  proved 
negative. 
A  second  portion  of  material  (part  of  an  inflorescence)  was 
received  July  19,  1910.  A  part  of  this  material  was  subjected  to  the 
treatment  and  tests  described  above  and  with  the  same  result — abso- 
lutely negative. 
While  these  observations  and  experiments  do  not  absolutely 
prove  Rhus  Michauxii  to  be  innocuous,  the  evidence  is  most  con- 
vincing and  the  author  is  of  the  opinion  that  further  investigations 
(should  they  be  made)  will  but  furnish  additional  evidence  in  sup- 
port of  Curtis'  contention,  made  forty  years  ago,  that  the  species  is 
entirely  harmless. 
BIBLIOGRAPHY. 
Michaux,  1803,  Flor.  Bor.  Am.,  (1)  182.  Earliest  description  of  Rhus 
pumilum  (now  R.  Michauxii) . 
Pursh,  18 14,  Flor.  Am.  Sep.,  (1)  204.  First  account  of  the  poisonous  proper- 
ties of  Rhus  pumilum. 
Bigelow,  1820,  Am.  Med.  Bot.,  (3)  25.  "  It  is  said  that  some  other  species 
of  Rhus,  such  as  Rhus  pumilum  and  Rhus  typhinum,  possess  the  same 
(poisonous)  property  in  a  greater  or  less  degree." 
Elliott,  1821,  Sk.  Bot.  So.  Car.  &  Ga.,  (1)  362.  R.  pumilum  listed  as  poisonous. 
De  Candolle,  1825,  Pro.  syst.  nat,  (2)  67.  "  Said  to  be  the  most  poisonous 
species." 
Rafinesque,  1830,  Med.  Flor.  U.S.,  (2)  257.  R.  pumilum  listed  among  the 
poisonous  species. 
Eaton,  1833,  Man.  Bot.  N.  Am.,  ed.  6,  303.  R.  pumilum  classed  as  poisonous. 
Gray,  1838,  joint  author;  see  Torrey. 
Lindley,  1838,  Flor.  Med.,  286.    ".    .    .    the  most  venomous  of  all." 
Torrey  and  Gray,  1838,  Flor.  N.  Am.,  (1)  217.    "A  very  poisonous  species." 
Dietrich,  1840,  Syn.  plant.,  (2)  1002.    "  A  most  poisonous  tree." 
Eaton  and  Wright,  1840,  N.  Am.  Bot.,  392.    Description  of  R.  pumila;  classed 
as  poisonous. 
Wright,  1840,  joint  author;  see  Eaton. 
Loudon,  1844,  Arb.  Fruct.  Brit.,  (2)  552. 
Griffith,  1847,  Med.  Bot,  185.  "  Many  other  species  of  Rhus  possess  the  same 
(poisonous)  properties,  in  a  greater  or  less  degree,  among  which  R. 
venenatum  and  R.  pumilum,  both  natives  of  this  country  (America),  are 
