ON  THE  ACTIVE  PRINCIPLE  OF  CATALPA  BIGNONOIDES.  205 
presents  a  beautiful  appearance,  with  its  large  and  handsome 
pyramidal  panicles  of  flowers  peering  through  the  bright  green 
foliage.  The  flowers,  too,  do  not  appear  the  less  handsome  upon 
close  examination,  being  of  a  pure  white,  mottled  with  rich 
purple  and  orange-yellow  spots  in  the  throat,  and  possessing  a 
very  pleasant  fragrance. 
After  the  early  frosts  of  autumn  have  stripped  the  tree  of  its 
leaves  there  remain  suspended  the  cylindrical  pods,  generally  a 
foot  in  length  ;  these  split  transversely  to  the  partition,  which 
extends  the  full  length  of  the  pod.  The  seeds  are  numerous, 
thin,  flat  and  enclosed  in  a  delicate  silky  envelope,  prolonged  at 
both  ends  into  finely  fringed  wings. 
As  to  the  medicinal  activity  of  the  various  parts  of  Catalpa 
there  seems  to  exist  a  variety  of  contradictory  opinions  ;  while 
many  assert  the  poisonous  nature  of  the  bark,  others  give  to  it 
valuable  antiperiodic  properties.  A  decoction  of  the  seeds,  too, 
has  been  recommended  in  cases  of  asthma,  although  their  perfect 
tastelessness  does  not  seem  to  indicate  any  medicinal  activity. 
Owing  to  the  latter  fact  chieflv,  the  following  investigations  were 
confined  to  the  bark,  and,  moreover,  to  perfectly  new  and  care- 
fully dried  specimens.  The  outer,  corky  layer  was  rejected, 
and  the  remaining  part  or  liber  retained  for  examination  ;  this 
was  of  a  cream  color,  and  possessed,  before  drying,  a  rank  odor 
and  a  nauseous  intensely  bitter  taste.  It  seemed  composed  of 
several  superimposed  sections  of  a  pithy  nature,  separated  by 
tough  fibrous  layers,  which  rendered  the  comminution  of  the  bark 
very  difficult.  :ii^****>i<* 
Exp.  III.  An  alcoholic  tincture  of  two  and  a  half  pounds  of 
powdered  bark  was  made  with  stronger  alcohol.  The  resulting 
tincture  was  of  a  deep  amber  color  and  possessed  the  peculiar 
odor  and  taste  of  the  bark. 
With  reagents  the  following  results  were  obtained :  with  salts 
of  the  FegOs  a  greenish  black  coloration  was  produced,  showing 
the  presence  of  tannin. 
By  the  addition  of  alkalies  a  red  coloration  was  produced,  and 
with  BaCl  a  light  yellow  flocculent  precipitate  resulted. 
The  alcoholic  tincture  was  then  concentrated  and  evaporated 
to  the  consistence  of  a  soft  extract.    This  was  then  freely  washed 
