Am.  Jour.  Pharm.) 
November,  1904.  / 
Anatomy  of  Edible  Berries. 
543 
but  isodiametric  in  the  inner  portion  and  contain  aleurone  grains  and 
fat.  In  the  outer  cells  the  walls  are  ot  even  thickness  (about  0-002 
millimeter),  but  in  the  centre  of  the  seed  they  frequently  have  knotty 
thickenings  {Fig.  19). 
Microscopic  Examination  of  Red  Currant  Preserves. — Cells  of  the 
endocarp  are  the  most  conspicuous  and  characteristic  elements  of 
currant  preserves.  Fragments  of  the  epidermis  and  floral  parts  are 
also  evident,  but  are  of  less  value  in  identification.  The  outer  gela- 
tinous coat  of  the  seed  is  destroyed  by  cooking,  but  the  crystal 
layer  and  the  inner  epidermis  retain  their  original  form  and  may  be 
identified  in  surface  mounts  prepared  by  warming  the  seed  in  dilute 
potash  solution  and  scraping  with  a  scalpel.  Sections  of  the  seed 
are  sometimes  useful,  but  as  a  rule  an  examination  of  the  testa  in 
surface  view  is  sufficient. 
This  species  does  not  occur  native  in  America,  the  cultivated 
varieties  of  both  Europe  and  America  being  derived  entirely  from 
European  stock. 
Macroscopic  Structure. — In  external  appearance  the  fruit  of  this 
species  is  distinguished  from  the  red  currant  by  its  black  color  and 
by  the  longer  floral  parts.  The  seeds  are  somewhat  smaller  and 
more  numerous  (about  fifteen  in  each  berry)  than  in  the  red  varieties. 
The  calyx  is  about  7  millimeters  long,  and  the  lobes  are  reflexed. 
Fig.  19. — Red  currant. 
Transverse  section  of  cen- 
tral portion  of  endosperm. 
X  300. 
Fig.  20.— Red  currant.  Testa  and 
endosperm  in  surface  view.  Signifi- 
cation of  letters  same  as  in  Fig.  18. 
X  3°o- 
the  black  currant  [Rides  nigrum  L.). 
