314 
Arbutin  in  Ericaceous  Plants. 
f  Am.  Jour.  Pharm. 
\     July  1, 1874. 
with  alcohol  to  precipitate  the  gum.  The  precipitate  dissolved  in 
water  was  treated  with  neutral  acetate  of  lead,  which  removed  color- 
ing matter ;  and  in  the  filtrate,  after  the  removal  of  the  lead  and  con- 
centration, a  white  precipitate,  answering  to  tests  for  gum,  was 
obtained  by  alcohol. 
The  filtrate  from  which  the  impure  gum  was  removed,  was  concen- 
trated, agitated  with  ether,  and  from  the  decanted  ether,  on  sponta- 
neous evaporation,  needles  were  deposited  on  the  sides  of  the  capsule, 
which  left  a  residue  on  ignition,  consisting  of  calcium  and  potassium. 
The  acidulous  radical  corresponding  in  behavior  with  the  fluorescent 
principle  contained  from  the  salt,  which  was  obtained  from  the 
neutral  acetate  of  lead  precipitate. 
The  proximate  constituents  of  the  bark  are  a  crystallizabe  fluores- 
cent acid,  a  bitter  principle  (uncrystallizable),  a  principle  resembling 
saponin,  tannin,  two  resins,  fatty  matter,  gum,  glucose  and  starch. 
Two  troy  ounces  of  the  bark'were  incinerated  and  yielded  twenty- 
four  grains,  or  two-and-a-half  per  cent,  of  ashes,  which  contained 
carbonic,  sulphuric,  phosphoric  and  silicic  acids  ;  potassium,  sodium, 
calcium,  magnesium  and  iron  bases. 
The  buttonbush  or  swamp  dogwood  belongs  to  the  natural  order  of 
Rubiacece,  is  a  shrub  growing  to  the  height  of  ten  or  fifteen  feet  and 
is  found  in  Canada  and  the  United  States,  growing  in  swamps  and  on 
the  margin  of  ponds  and  brooks.  The  flowers  are  white  and  congre- 
gated in  peduncled  spherical  heads,  which  give  to  the  shrub  quite  a 
characteristic  appearance. 
ON  THE  OCCURENCE  OF  ARBUTIN  IN  ERICACEOUS  PLANTS. 
By  John  M.  Maisuh. 
Arbutin  was  discovered,  in  1851,  in  the  leaves  of  Uva  ursi  by  Kawa- 
lier,#  and  recognized  as  a  glucoside,  splitting  into  sugar  and  arctuvin. 
The  latter  body  was  further  investigated  by  A.  Streeker,  and  in  1858 
announced  to  be  identical  with  hydrokinone,|  the  nitro-compounds  of 
which  were  more  fully  described  by  him  in  1861. j  In  1859,  Uloth 
found  in  the  dry  distillate  of  the  extract  of  several  ericaceous  plants 
(Chimaphila  umbellata,  Calluna  vulgaris,  Ledum  palustre  and  Vac- 
*  See  American  Journal  of  Pharmacy,  1853,  p.  68. 
f  Annal.  d.  Chem.  und  Pharm. ,  cvii,  228. 
%  Ibid,,  cxviii,  p.  292. 
