392  Chemical  Investigation  of  Macallo  Bark.  {  *m)?™\!7)Mm' 
whitish  silky-like  crystals  of  cornin  were  left,  together  with  some  color- 
ing matter. 
The  crystals  formed  in  the  beaker  from  alcohol  solution  were  then 
treated  by  the  same  method  as  the  latter  portion,  and  the  crystalline 
mass  left  was  added  to  the  other,  dissolved  in  sufficient  strong  alcohol, 
and  the  solution  mixed  with  three  parts  of  pure  ether  ;  after  standing  a 
day  the  clear  solution  was  decanted  from  the  sediment  and  left  to  evap- 
orate. The  treatment  with  alcohol  and  ether  had  to  be  repeated  sev- 
eral times  in  order  to  obtain  the  crystals  of  cornin  with  only  a  small 
amount  of  coloring  matter. 
A  portion  of  the  impure  crystals  was  dissolved  in  sufficient  strong 
alcohol  and  kept  in  a  corked  wide-mouth  bottle,  when  the  cornin  crys- 
tallized out  in  white  silky  crystals,  which  were  removed  and  dried  on 
bibulous  paper,  when  they  assumed  a  slight  coloration. 
The  cornin  was  also  obtained  in  pure  crystals  by  repeated  recrystal- 
lization  from  strong  alcohol,  and  pouring  off  the  colored  mother-liquor, 
which  contained  most  of  the  bitter  principle- 
Thus  obtained,  cornin  is  in  white  or  nearly  white  silky  crystals,  very 
bitter,  very  soluble  both  in  alcohol  and  water,  less  so  in  ether.  A  solu- 
tion in  water  is  not  affected  by  solution  of  iodine,  corrosive  sublimate, 
perchloride  of  iron,  neutral  acetate  of  lead,  or  chloride  of  barium,  and 
is  but  slightly  darkened  by  hydrate  of  ammonium  and  potassium. 
Basic  acetate  of  lead  gives  a  slightly  colored  precipitate.  Nitrate  of 
silver  yields  a  white  precipitate,  which  soon  becomes  dark  and  is  entirely 
dissolved  in  diluted  nitric  acid. 
The  results  agree  in  all  essential  points  with  those  previously  obtained 
by  Geiger,  as  reported  in  Gmelin's  "  Chemistry." 
Chemical  Investigation  of  the  Bark  of  a  Plant  known  in  Tabasco 
as  MACALLO  and  in  Yucatan  as  YABA. 
By  Juan  Donde. 
(Translated  and  abridged  from  "  La  Emulacion,"  March,  1879,  by  w-  Barbeck.) 
The  macallo  bark,  examined  by  me,  was  in  pieces  about  75  centi- 
meters long,  from  10  to  30  centimeters  broad  and  about  ij-  or  2  centi- 
meters thick.  The  thick  periderm  is  of  a  light-gray  color,  with  irreg- 
ularly circular  spots,  which  are  either  greenish-white,  or  the  larger  ones 
cr.etaceous  white  j  it  has  numerous  deep  longitudinal  fissures,  is  readily 
