248  Dr.  W,  G.  Boor  studs  Plumierid.  {Am--jg£;$£Tm' 
to  crystallize.  Dry  crystals  between  filter  paper  and  remove  the 
odor  of  amyl  alcohol  by  warming. 
The  bitter  taste  of  the  crystals  is  to  be  detected  in  a  1:15,000. 
solution  (Plumierid  is,  therefore,  much  less  bitter  than  quinine, 
which  is  to  be  detected  in  a  1:50,000  dilution.  Referent.) 
Plumierid  does  not  contain  nitrogen.    Its  solutions  are  neutral. 
Plumierid  does  not  reduce  Fehling's  fluid,  when  boiled  with  dilute 
acids ;  it  is,  therefore,  an  indifferent  bitter  principle. 
Plumierid  crystallizes  with  2-5  per  cent,  water  of  crystallization. 
It  commences  to  char  at  1500  C,  but  has  not  melted  at  2000  C. 
Platinic  chloride,  gold  chloride,  silver  nitrate,  lead  acetate,  lead 
subacetate,  mercuric  chloride,  potassium  mercuric  iodide,  picric 
acid,  nor  tannin  solutions  produce  a  precipitate  in  its  watery 
solution,  1:20. 
Sulphuric  acid  dissolves  it  with  an  intense  yellow  color.  A 
greenish  black  precipitate  is  thrown  down  in  24  hours,  while  the 
fluid  is  violet. 
Potassium  dichromate,  added  to  its  solution  in  sulphuric  acid, 
gives  green  stripes.  (Great  caution  is  needed  where  green  colors 
appear  after  the  addition  of  potassium  dichromate,  not  to  draw  a 
wrong  conclusion.  Referent.) 
Nitric  acid  dissolves  it  colorless.  This  solution  leaves  a  yellow 
red  residue  when  evaporated. 
Hydrochloric  acid  dissolves  it  colorless  in  the  cold.  The  solution 
soon  becomes  yellow  and  red ;  a  brown  precipitate  settles  down 
after  24  hours,  while  the  fluid  is  violet.  The  solution  is  immedi- 
ately yellow  and  red  when  a  few  mgr.  of  Plumierid  are  boiled  with 
1  c.c.  HC1.  This  solution,  too,  discolors  and  throws  down  a  dark 
brown  precipitate.  The  filtrate  has  dichroistic  properties ;  is  red 
by  transmitted  light,  blue  by  reflected  light.  (Those  dichroistic 
properties  from  boiling  with  HC1  remind  one  of  Resorcinol  reac- 
tions. Referent.)  A  purple-blue  colored  fluid  is  obtained  by  dilution 
with  water.  An  excess  of  caustic  soda  or  ammonia  changes  the 
color  to  orange. 
Plumierid  has  the  formula  C30H40O18.H2O.    It  is  not  poisonous. 
The  genus  Plumiera  seems  to  be  rather  remarkable  from  a  phyto- 
chemical  standpoint.  Peckolt  obtained  a  crystalline  alkaloid  from 
P.  lancifolia,  which  he  called  agoniadine ;  P.  drastica  is  a  very 
active  purgative. 
