Am"se°pUtr'i9i9rm' ^    Standardisation  of  Piscidia  erythrina.  581 
two  or  three  days,  crystals  separated  upon  the  sides  and  bottom  of 
the  beaker.  They  were  accompanied  by  a  resinous  substance  from 
which  they  were  purified  by  recrystallization  from  alcohol.  By 
adding  water  to  the  mother  liquor  a  second  crop  of  impure  "pis- 
cidia "  was  obtained.  These  purified  crystals  possessed  all  of  the 
properties  assigned  to  "  piscidia  "  by  Hart. 
We  have  repeated  the  work  of  Hart  and  Berberich  with  the  ex- 
ception of  the  melting  point  determination  and  elementary  analysis 
and  have  obtained  the  same  results  noted  by  them. 
A  modification  of  the  lime  method  of  isolation  of  piscidin  was 
developed  in  the  hope  that  it  might  be  applicable  to  the  assay  of 
fluid  extract  of  Jamaica  dogwood  by  chemical  means.  The  details 
were  as  follows :  100  Mils  of  the  fluid  extract  were  placed  in  a 
centrifuge  bottle  which  had  been  tared  with  10  Gms.  of  U.  S.  P. 
slaked  lime  in  it.  The  bottle  with  its  contents  was  weighed  to  obtain 
the  weight  of  the  sample  and  the  bottle  was  stoppered  and  allowed 
to  stand  with  frequent  agitation  at  40-500  C.  for  a  half  hour.  The 
bottle  was  then  centrifuged  and  as  much  of  the  clear  liquid  as  pos- 
sible was  removed  and  filtered  into  a  tared  250  Mils  Erlenmayer. 
The  Erlenmeyer  was  weighed  to  obtain  the  weight  of  the  sample. 
The  sample  was  diluted  with  3^  times  its  weight  of  freshly  boiled 
and  cooled  distilled  water.  The  Erlenmayer  was  then  corked  well 
and  allowed  to  stand  at  room  temperature  for  three  days  with  occa- 
sional agitation.  The  crystallized  piscidin  was  filtered  off  on  a 
tared  Gooch,  washed  with  15  per  cent,  alcohol  and  dried  at  ioo°  C. 
to  constant  weight.  Some  of  the  piscidin  adhered  tenaciously  to  the 
flask,  so  the  flask  was  weighed  to  obtain  the  weight  of  the  adherent 
piscidin,  which  was  then  added  to  the  weight  of  the  piscidin  found 
in  the  Gooch. 
Dilution  of  the  aliquot  with  3^  times  its  weight  of  water  was 
decided  upon  as  yielding  the  maximum  proportion  of  piscidin,  as 
shown  by  the  following  experiments  on  one  fluid  extract : 
Experiment  No. 
Aliquot. 
Water  Added. 
Piscidin. 
I 
50  Mils 
50  Mils 
0.182  Gm.  per  100  Mils 
2 
175  " 
0.219    "      "     "  " 
3 
500  " 
0.220   "      "     "  " 
The  piscidin  yielded  by  this  process  is  contaminated  by  resinous 
matter.    Separation  of  the  piscidin  and  resin  was  attempted  by 
