no 
Alkaloids  in  Belladonna  Plant. 
Am.  Jour.  Pharm. 
March,  1914. 
It  has  been  quite  generally  held  that  most  of  the  alkaloids  in  the 
roots  are  found  in  the  bark.  The  National  Dispensatory  states  that 
a  good  root  contains  alkaloids  in  the  parenchymal  tissue  of  all  parts 
though  mostly  in  the  bark,  while  in  a  woody  root  it  is  almost  ex- 
clusively in  the  bark.  This  investigation  appears  to  indicate  that 
such  is  not  always  the  case.  In  all  of  the  four  three-year  old  plants 
analyzed,  the  woody  part  of  the  roots  was  richer  in  alkaloids  than 
the  bark.  In  order  to  obtain  further  data  on  this  question,  seven 
four-year  old  plants  were  dug  up  early  in  the  fall  and  the  roots 
separated  into  bark  and  wood.  Table  V  shows  the  results  of  the 
assays. 
Table  V. 
Comparison  of  Alkaloidal   Content  of  the  Bark  and  Wood  of  the  Roots  oj 
Individual  Belladonna  Plant. 
Number  of  plant 
Alkaloids  (per  cent.) 
Bark 
O.I82 
O.163 
0.262 
O.I44 
O.205 
O.238 
O.227 
Wood 
0.217 
O.177 
O.324 
O.29O 
0.347 
O.447 
O.400 
These  results  show  further  that  the  bark  is  not  always  richer  in 
alkaloids  than  the  woody  tissue. 
It  has  been  pointed  out  that  the  small  leaves  were  found  to  be 
almost  invariably  richer  than  the  large  leaves.  This  is  a  matter  of 
some  importance  in  that  it  becomes  a  factor  in  the  method  of  pick- 
ing leaves  with  regard  to  securing  those  of  greatest  medicinal  value. 
To  establish  this  fact  more  conclusively,  large  and  small  leaves  were 
picked  from  the  individual  belladonna  plants.  At  the  same  time 
leaves  were  also  picked  from  a  number  of  species  of  Datura.  Table 
VI  shows  the  relative  percentage  of  alkaloids  in  the  leaves. 
It  will  be  noticed  that  in  only  one  instance,  plant  No.  2, 
does  the  sample  of  large  leaves  show  a  greater  percentage  of  alkaloids 
than  the  smaller.  In  all  the  others  the  difference  is  greatly  in  favor 
of  the  small  leaves,  as  is  also  indicated  by  the  averages.  All  but  one 
of  the  Datura  species  indicated  the  same  condition,  thus  showing 
