210 
Rhus  Aromatica. 
{ 
Am.  Jour.  Pharm. 
May,  1881. 
whitish  or  flesh-colored^  and  striate.  The  bark  is  brittle,  breaks  with 
a  somewhat  granular  fracture,  yields  an  ochre-colored  powder,  and  has 
a  distinct,  rather  pleasant  odor,  more  marked  when  green  than  when 
dry ;  its  taste  is  astringent,  aromatic  and  slightly  bitter  when  fresh, 
with  a  flavor  peculiar  to  the  plant  from  which  it  is  derived.  It  should 
be  collected  in  the  spring  of  the  year. 
Ijeaves  of  Rhus  Aromatica,  Aifoti. 
Upon  microscopical  examination  the  bark  appears  to  be  radially  and 
tangentially  striate,  and  is  marked  throughout  with  oil  tubes  and  crys- 
tals, as  is  shown  in  the  accompanying  drawing. 
Fig.  I.  A  transverse  section  of  the  bark  magnified  to  about  forty 
or  fifty  diameters.  The  epidermis  consists  of  a  single  row  of  cells, 
the  walls  of  which  are  of  a  dark  brown  color.  The  corky  layer  is 
somewhat  lighter  brown,  and  the  cells  number,  radially,  from  sixteen 
to  twenty-five ;  mostly,  however,  eighteen.    The  first  layer  beneath 
