252  Accurate  Estimation  of  Quinia.  {km^%f^"m' 
it  with  animal  charcoal.  Elementary  analyses  prove  Hausmann's  for- 
mula for  betulin,  C36H60O3  and  C36H580(C2H302)2,  his  formula  for  the 
acetate,  which  consists  of  long,  colorless  needles,  correct. — Ber.  d. 
Deutsch.  Chem.  Ges.y  1879,  p.  7. 
Daphnetin  was  obtained  by  Carl  Stuenkel  by  dissolving  commercial 
extract  of  daphne  mezereum  in  alcohol,  heating  with  hydrochloric  acid  in 
order  to  split  the  glucoside  daphnin,  existingin  the  solution,  into  daphnetin 
and  sugar,  evaporating  the  liquid  on  a  water-bath  until  only  traces  of  HC1 
continue  to  evaporate,  boiling  the  black  residue  repeatedly  with  water, 
msxingthe  reddish-brown  decoctions,  condensing, adding  a  small  quantity 
of  neutral  lead  acetate  to  remove  the  coloring  matter,  etc.,  then  by  con- 
tinued fractional  precipitations  effecting  a  combination  of  daphnetin  and 
lead  oxide,  which  was  decomposed  by  sulphuretted  hydrogen,  when  a 
comparatively  pure  daphnetin  was  obtained,  which  was  purified  by  boil 
ing  with  animal  charcoal.  Daphnetin  is  soluble  in  boiling  water,  more 
so  in  diluted  alcohol,  crystallizing  from  thsse  solutions  in  yellowish- 
white  prisms,  is  scarcely  soluble  in  ether,  benzol,  chloroform  and  car- 
bon bisuiphuret,  forms  red  solutions  with  concentrated  H2SOi  and 
HC1,  is  precipitated  from  these  by  water  and  forms  reddish-yellow 
solutions  with  caustic  alkalies  and  alkaline  carbonates. — Ber.  d.  Deutsch. 
Chem.  Ges.,  1879,  p.  109. 
Lactucon  is  made  by  Wigman  by  extracting  lactucarium  prepared 
from  Lactuca  altissima,  first  with  water,  then  with  diluted  alcohol, 
and  boiling  the  residue  with  90  per  cent,  alcohol.  Wart-like  granules 
were  obtained  on  cooling,  which,  after  being  treated  with  animal  char- 
coal and  recrystallized  several  times  from  alcohol,  proved  to  be  groups 
of  microscopic  needles.  They  melt  at  296°C,  become  amorphous, 
are  insoluble  in  water,  scarcely  soluble  in  alcohol,  but  readily  soluble  in 
petroleum.  The  author  considers  lactucon  homologous  with  camphor 
and  Paterno's  zeorin. — Ber.  d.  Deutsch.  Chem.  Ges.^  1879,  p.  10. 
NOTE  ON  THE  MORE  ACCURATE  ESTIMATION  OF 
QUINIA  IN  FERRI  ET  QUINIA  CITRAS,  B.  P. 
By  W.  Stevenson. 
The  Pharmacopoeia  process  for  the  estimation  of  quinia  in  ferri  et 
quiniae  citras  frequently  occasions  some  difficulty  as  regards  the  amount 
of  washing  required  by  the  precipitated  quinia.     If  the  whole  of  the 
