TIME  FOR  COLLECTING  THE  LEAVES  OF  DIGITALIS.  221 
ON  THE  BEHAYIOUR  OF  NARCEINA  TO  IODINE. 
By  W.  Stein. 
Dragendorff  has  described  a  reaction  of  narceina  wliicli  with  po- 
tassio-iodide  of  zinc  yields  hair-like  crystals,  which  are  gradually 
turned  blue.  According  to  Stein,  this  is  due  to  narceina  being 
colored  blue  by  iodine.  Solid  narceina,  like  starch,  becomes 
blue  by  free  iodine.  Winkler  and  Pelletier  have  already  ob- 
served this  reaction,  but  Winkler  did  not  find  it  reliable  in  all 
cases.  Much  iodine  turns  narceina  brown  ;  but  if  water  is  now 
added  and  the  excess  of  iodine  removed  by  ammonia,  the  blue 
color  appears.  An  excess  of  ammonia,  like  all  substances  which 
dissolve  narceina,  prevent  the  reaction.  In  solutions  the  alka- 
loid is  recognized  by  adding  potassio-iodide  of  zinc  with  a  drop 
of  solution  of  iodine,  and  agitating  with  ether.  In  this  way  1 
narceina  in  2500  water  may  still  be  recognized.  No  other  opium 
alkaloid  has  a  similar  behaviour. — Zeitschr.f,  Chemie,  1869,  from 
Journ.  f.  prakt,  Qhem.^  cvi,  310. 
ON  THE  TIME  FOR  COLLECTING  THE  LEAVES  OF  DIGI- 
TALIS. 
By  F.  Schneider. 
The  pharmacopoeias  and  text  books  direct  to  collect  these 
leaves  of  the  flowering  plant.  I  had  the  leaves  annually  col- 
lected in  the  black  forest  during  the  latter  part  of  May  or  begin- 
ning of  June,  requiring  always  some  flowering  stems.  In  ap- 
pearance I  had  a  beautiful  drug,  but  rarely  could  I  get  a  satis- 
factory reaction  by  tannin  and  ferrocyanide  of  potassium  in  the 
infusion.  In  1869  a  botanical  friend,  formerly  apothecary, 
offered  to  supply  digitalis,  which  he  collected  near  the  end  of 
August  and  beginning  of  September,  as  he  had  done  during  his 
long  pharmaceutical  practice,  from  the  rosulate  leaves  of  plants, 
flowering  the  following  year.  The  digitalis  yielded  a  deeply 
colored  infusion  of  strong  odor  and  taste,  and  gave  with  tannin  at 
once  a  dense  precipitate,  with  ferrocyanide  of  potassium  after  12 
to  15  minutes  a  strong  turbidity.  The  leaves  should,  therefore, 
be  collected  not  in  the  flowering  season,  but  late  in  summer. — 
Pharm.  Centr.  Halle,  1869,  No.  49,  from  Scliweiz.  Wochenschr, 
/.  PA. 
