542 
Anatomy  of  Edible  Berries. 
(  Am.  Jour.  Pharm. 
I  November,  1904. 
colorless,  the  thick  membrane,  brown.  Each  cell  contains  a  single 
monoclinic  crystal,  which  nearly  or  completely  fills  the  cell  cavity. 
With  crossed  Nicol  prisms  these  crystals  appear  as  luminous  spots 
in  the  black  background,  disappearing  on  addition  of  a  drop  of 
hydrochloric  acid.  In  section  it  may  be  seen  that  only  the  radial 
and  inner  walls  are  thickened  and  that  as  a  consequence  each  crystal 
lies  close  to  the  thin  outer  wall. 
(4)  Inner  Epidermis  (Figs.  18  and  20,  iep) — Like  the  crystal  layer, 
the  inner  epidermis  is  of  a  deep  brown  color,  but  this  color  is  due 
Fig.  18. — Red  currant  seed  in  transverse  section.  S,  testa  consisting  of  aep, 
gelatinous  outer  epidermis,  p,  parenchyma  (nutritive  layer),  k,  crystal  layer, 
iep,  brown  layer  (inner  epidermis);  N,  hyaline  layer  (nucellus);  B,  endosperm. 
X  3°°- 
to  cell  contents,  not  to  thickened  cell  walls.  The  cells  are  longi- 
tudinally elongated,  varying  in  length  up  to  0*15  millimeter  and  in 
width  from  0-004  to  0*009.  Both  this  layer  and  the  crystal  layer 
are  readily  separated  from  the  endosperm  by  soaking  in  dilute  pot- 
ash and  scraping. 
Nucellar  Layer  (Fig.  18,  N). — A  cross  section  of  the  seed  shows  a 
cellulose  band  about  o-oi  millimeter  thick  between  the  testa  and  the 
endosperm,  consisting  of  the  obliterated  cells  of  the  nucellus. 
The  Endosperm  (Figs.  18  and  20,  E)  fills  the  larger  part  of  the 
seed  cavity.    The  cells  are  mostly  elongated  in  the  outer  layers, 
