358 
Ipomcca  Horsfallicc. 
/Am.  Jour.  Phami. 
\     August,  1910. 
activity  is  considerably  lower  than  that  of  either  of  the  above- 
mentioned  resins,  and  appears  to  approximate  most  nearly  to  that 
of  the  resin  from  Ipomcea  orizabensis,  Ledanois,  which  has  been 
recorded  by  Guigues  (loc.  cit.)  as  varying-  from  — 23.30'  to  — 250. 
Extraction  of  the  Resin  with  Various  Solvents. 
A  small  portion  of  the  resin  (1.0  gramme)  was  reserved  for  a 
physiological  test,  and  the  remainder  (7.6  grammes)  dissolved  in 
alcohol,  the  solution  being  brought  onto  prepared  sawdust,  and 
the  mixture  thoroughly  dried.  It  was  then  successively  extracted 
with  light  petroleum,  ether,  and  alcohol,  when  the  following  amounts 
of  extract,  dried  at  ioo°  C,  were  obtained: 
Petroleum (b.  p.  40-600  C.)  extracted  4.92  grammes,  or  64.7  per  cent. 
Ether  extracted  1.90  grammes,  or  25.0  per  cent. 
Alcohol  extracted  0.60  grammes,  or    8.0  per  cent. 
Total  7.42  grammes,  or  97.7  per  cent. 
Petroleum  Extract. — This  was  a  soft,  brown  resin.  It  was 
heated  in  a  reflux  apparatus  with  an  alcoholic  solution  of  potas- 
sium hydroxide  for  several  hours,  after  which  the  alcohol  was  re- 
moved, water  added,  and  the  alkaline  mixture  extracted  with  ether. 
The  ethereal  liquid  was  dried,  and  the  solvent  evaporated,  when  a 
small  quantity  of  solid  material  was  obtained.  This  yielded  a  little 
of  a  crystalline  substance,  which  melted  at  i32-i33°  C,  and  gave 
the  color  reactions  oi  the  phytosterols. 
The  alkaline  liquid  which  had  been  extracted  with  ether  was 
acidified,  and  again  extracted  with  this  solvent,  the  ethereal  liquid 
being  dried  and  evaporated.  A  small  amount  of  acid  was  thus 
obtained,  which  was  distilled  under  diminished '  pressure,  when  it 
partially  solidified.  The  oily  portion  was  unsaturated,  since  it 
absorbed  bromine  in  chloroform  solution.  The  solid  portion  was 
recrystallized  from  dilute  acetic  acid,  when  it  melted  at  56-580  C. 
It  was  thus  evident  that  the  original  product  consisted  of  a  mixture 
of  acids,  but  the  amount  was  too  small  to  permit  of  their  further 
separation. 
Ether  Extract. — This  extract,  like  the  preceding  one,  was  a 
soft,  brown  resin.  On  redissolving  it  in  ether  a  very  small  amount 
of  a  sparingly  soluble  substance  separated,  which  was  collected. 
This  was  found  to  give  a  color  reaction  similar  to  that  yielded  by 
