524  Purshia.  { ^v^ffi™- 
tion  left  a  dark-brown  extract,  partly  soluble  in  water.  The  aque- 
ous solution  gave  with  ferric  chloride  a  greenish-black  color,  and 
after  the  removal  of  the  tannin  by  means  of  gelatin,  yielded  with 
basic  lead  acetate  a  yellowish-white  precipitate,  from  which  a  light- 
yellow  extractive  mass  of  an  acid  reaction  was  isolated.  The  aque- 
ous solution  also  reacted  with  Fehling's  solution,  indicating  the 
presence  of  glucose.  The  alcoholic  extract  insoluble  in  water  was 
a  brownish  resinous  substance. 
The  bark,  exhausted  as  stated  above,  yielded  to  cold  water  some 
gummy  matter,  and  to  boiling  water  some  pectin  compounds  and 
starch,  the  latter  indicated  by  the  blue  color  with  iodine  solution. 
Experiments  made  in  search  of  an  alkaloid  or  glucoside  had  nega- 
tive results.  The  ash  obtained  from  the  dried  bark  amounts  to  jy2 
per  cent. 
The  organic  constituents  determined  by  these  experiments,  are 
orange-red  coloring  matter,  several  resins,  tannin,  vegetable  acid, 
glucose  and  starch. 
See  also  analysis  of  Celastrus  scandens,  by  C.  H.  Bernhard,  in 
American  Journal  of  Pharmacy,  1882,  pp.  1-5. 
PURSHIA. 
By  Dr.  V.  Havard,  Surgeon  U.  S.  A. 
Read  at  the  Pharmaceutical  Meeting  of  the  Philadelphia  College  of  Pharmacy,  October 
20,  1891. 
Pursliia  tridentata,  DC.  This  monotypic  genus  of  the  order 
Rosaceae  (and  named  in  honor  of  Pursh,  one  of  our  most  successful 
botanical  pioneers)  is  characterized  by  solitary  carpels  becoming 
dry  akenes,  exserted,  conical-pointed  and  minutely  grooved,  and  con- 
taining a  dark  brown  seed,  oblong-obovate,  about  three  lines  long, 
without  albumen. 
A  diffusely-branched  shrub,  3  to  5  feet  high,  with  small  fascicled 
leaves  cuneate-obovate,  3-lobed  at  the  apex,  and  solitary  flowers, 
terminal  on  the  short  branches,  the  five  yellow  petals  exceeding  the 
calyx  lobes. 
Common  throughout  the  Rocky  Mountain  region,  covering  foot- 
hills and  slopes,  from  Arizona  and  New  Mexico  to  the  British  bound- 
ary, and  westward  to  the  Sierra  Nevada.  "Almost  the  only  shrub 
to  be  seen  through  an  immense  tract  of  barren  soil  from  the  head 
