Am.  Jour.  Pharm, 
June,  1896. 
North  American  Conifer ce. 
32S 
would  make  it  valuable  for  that  constituent  in  the  absence  of  other 
resinous  pines.  The  wood  is  quite  hard  and  durable,  and  is  used  in 
nearly  all  kinds  of  construction. 
PINUS  GLABRA,  WALTER. 
SPRUCE  PINE. 
GENERAL  CHARACTERS  AND  OCCURRENCE. 
This  is  a  small- sized  tree,  40  to  60  feet  high,  branching  from  near 
the  ground,  having  whitish  and  smooth  branchlets,  and  usually 
solitary  cones,  which  are  about  2  inches  long  and  have  the  scales 
nearly  destitute  of  spines.    The  wood  of  the  tree  is  soft  and  white. 
Fig.  jo,  cross-section  of  leaf  of  Pinus  glabra,  magnified  100  diameters.  St, 
stoma  ;  hy,  hypoderma  ;  sec.  r.,  secretion  reservoir  ;  xy,  xylem  of  one'of  the 
two  bundles. 
The  species  occurs  in  South  Carolina  and  Florida,  and  is  there 
known  as  the  spruce  pine. 
Its  leaves  are  in  twos,  slender,  scattered,  3  or  4  inches  long, 
from  a  sheath  about  i-  inch  long.  On  the  flat  surface  are  about'six 
rows  of  stomata,  and  on  the  convex  about  nine  rows. 
MICROSCOPICAL  STRUCTURE. 
The  cross-section  showed,  underneath  the  thick-walled  epidermis, 
a  usually  two-layered,  but  sometimes  only  one-layered,  hypoderma, 
the  outer  of  these  with  its  cell  walls  but  slightly  thickened,  the 
inner  with  its  walls  considerably  thickened.  The  secretion  reser- 
voirs are  usually  two  in  number,  one  opposite  each  of  the  angles  of 
