4i8 
North  American  Conifer  ce. 
( Am.  Jour.  Pharm. 
I      August.  1896. 
PICEA  EXCELSA,  LINK.-" 
NORWAY  SPRUCE. 
Although  not  originally  a  native  of  the  Western  Continent,  the 
Norway  spruce  has  become  so  firmly  established  in  this  country  as 
to  make  its  consideration  along  with  our  own  species  of  especial 
interest.  It  is  one  of  the  largest  and  finest  of  its  genus,  attaining 
a  height,  in  some  cases,  of  180  feet  and  a  diameter  of  6  feet. 
It  is  of  conical  form  ;  its  lower  branches  are  drooping  ;  the  bark  of 
the  trunk  is  rather  thin,  warty,  of  a  reddish-brown  color  and  becom- 
ing scaly  on  old  trees.  The  cones  are  cylindrical,  terminal,  pendant ; 
its  scales  are  naked,  flattish  and  truncate  at  the  apex.  The  cones 
are  large,  from  5  to  7  inches  long,  and  from  1^  to  2  inches  thick. 
The  species  is  widely  distributed  over  the  cooler  portions  of 
Europe  and  Asia.  It  is  common  in  Scandinavia,  Lapland,  Den- 
mark, northern  Germany,  the  Alps  (where,  at  an  elevation  of  4,000 
to  6,500  feet,  it  comprises  vast  forests),  Russia  and  Siberia. 
MICROSCOPICAL  STRUCTURE. 
A  cross-section  of  the  stem  of  two  years'  growth  showed  the  fol- 
lowing structure :  The  thick-walled  epidermis  was  supported  by 
only  about  one  layer  of  thick-walled  fibres.  Beneath  this  were 
several  layers  of  thin-walled,  large-sized  parenchyma  cells.  Inte- 
rior to  this  was  a  layer  of  periderm,  consisting  partly  of  stone  cells 
and  partly  of  thin-walled  cells  abounding  in  tannin.  Interior  to  this 
was  a  considerable  thickness  of  parenchyma,  containing  some  oleo- 
resin  cells  and  numerous  tannin  cells.  In  this  area  also  occurred  occa- 
sional crystal  cells,  similar  to  those  whose  occurrence  has  been  noted 
in  other  species  of  Picea  and  Pinus.  No  stone  cells  were  observed 
interior  to  the  periderm  layer.  The  bast  layer  was  without  fibres 
and  contained  numerous  small  tannin  cells.  The  xylem  had  the 
usual  structure  and  contained  but  little  tannin. 
The  leaves  of  this  species  are  from  \  to  |  inch  in  length  and  ^ 
inch  thick,  quadrangular,  prismatic,  pointed,  rigid,  deep  green,  and 
were  observed  to  have  from  three  to  five  more  or  less  interrupted 
rows  of  stomata  in  each  face.  The  epidermis  was  composed  of  small 
cells,  with  thick  and  strongly  cutinized  exterior  walls,  and  with  but 
moderately  thickened  inner  and  radial  walls.  The  hypoderma  was, 
at  the  angles,  two-layered,  elsewhere  one-layered,  and  was  com- 
posed of  thick-walled   cells.    The  mesophyll   was  composed  of 
