322 
PJiarmacoj^nosy  of  Echinacea. 
Am.  .lonr.  Pharm- 
.liily,  I'.ni. 
Fig.  5. 
Section  showing  development  of  oleoresin  canals  or  reservoirs  (a,  6,  c,  d  and  e);  o,  oleo- 
resin  canals;  p,  parenchyma.  F,  longitudinal  section  showing  an  elongated  secretory  cell 
between  the  rows  of  parenchyma  in  the  cortex. 
INTERCELLULAR  SUBSTANCE. 
The  Compositse  are  usually  divided  for  certain  anatomic/al 
reasons,  as  well  as  for  morphological  differences,  into  two  principal 
groups.  In  the  one,  viz.,  the  Tubuliflorae,  occur  oils  and  resins, 
either  in  intercellular  canals  or  secretory  cavities.    In  the  other, 
