Am'Feb.?Sarm*}  Eupatorium  Purpureum.  77 
tion  of  cold  water,  and  dry  it.  Then  boil  this  insoluble 
substance  in  an  appropriate  amount  of  officinal  alcohol,  filter 
and  upon  cooling  the  substance  separates  in  brownish-yellow 
crystals.  The  crystals  should  be  purified  by  recrystallization 
from  hot  alcohol,  when  they  assume  a  deep  yellow  color. 
"The  precipitate  that  sometimes  collects  in  fluid  extract 
of  Eupatorium  purpureum  usually  contains  a  considerable  pro- 
portion of  this  substance.  In  the  course  of  time,  a  large 
container  of  such  a  fluid  extract  forms  (as  other  liquids  also 
do)  zones  of  different  gravities  and  different  compositions. 
At  one  of  the  lines,  under  these  circumstances,  the  substance 
reaches  a  crystallizable  condition,  or  a  freedom  from  asso- 
ciates, that  permits  it  to  assume  a  crystalline  form,  and  it 
shoots  into  existence  in  masses  often  of  large  crystals. 
These  formations  are  likely  to  form  a  belt  ne^ir  the  top  of  the 
liquid  and  on  the  coolest  portion  of  the  container. 
"  Concerning  a  name,  since  both  names  of  the  plant  have 
been  appropriated  (purpurin  from  madder  and  eupatorin  from 
boneset),  it  seems  difficult  to  formulate  a  name  in  the  usual 
manner  (denoting  its  origin)  without  creating  confusion.  If 
your  chemical  examination  does  not  determine  it  to  be  iden- 
tical with  quercitrin  (which  I  doubt),  and  if  it  is  not  possessed 
of  characters  in  a  chemical  sense  that  will  permit  you  to  give 
it  an  acceptable  name  therefrom,  it  might  be  well  to  affix  a 
name  combining  the  generic  and  specific  names  of  the  plant, 
for  example,  Eupapurin,  or,  indeed,  the  briefer  name  Euparin 
might  be  better." 
Under  my  direction  Mr.  Eberhardt  made  an  investigation 
of  the  two  samples,  which  he  found  to  be  identical. 
The  purification  of  the  yellowish  brown  mass  was  accom- 
plished by  repeatedly  dissolving  in  hot  absolute  alcohol  and 
allowing  to  crystallize.  By  this  treatment  the  crystals 
became  more  distinctly  acicular,  and  of  a  lighter  yellow,  but 
with  a  decided  brownish  shade.  A  portion  was  then  taken, 
and,  after  solution  in  warm  alcohol,  digested  with  animal 
charcoal,  which  resulted  in  a  bright  lemon-yellow  product, 
although,  as  will  be  seen,  without  materially  changing  the 
composition. 
These  crystals  both  before  and  after  treatment  with  animal 
