646 
North  American  Coniferce. 
f  Am.  Jour.  Pharm. 
\  December,  1896. 
tained  tannin  in  abundance.  Secretion  reservoirs  were  not  present 
in  the  wood. 
Sections  of  the  older  bark  of  this  species  were  studied,  and  a 
description  published  some  time  ago  in  this  Journal  (July,  1895, 
p.  356).  Some  of  the  facts  and  illustrations  are  here  reproduced. 
It  was  shown,  Fig.  53,  that  successive  periderms  were  formed,  finally 
invading  the  inner  layer  of  the  bark.  These  bands  of  cork  were 
very  deep  purple,  and  the  coloring  matter  which  they  contained  was 
bleached  out  of  them  with  great  difficulty,  even  by  means  of  Labar- 
raque's  solution.  The  dead  parenchymatous  tissues  between  these 
were  also  seen  to  be  strongly  colored,  but  the  coloring  matter  was 
discharged  from  them  more  readily.  Whether  this  was  due  to  the 
greater  impenetrability  of  the  corky  bands  to  solvents,  or  to  differ- 
Fig.  55. — A  few  of  the  crystals,  magnified  230  diameters. 
ences  in  the  chemical  nature  of  the  coloring  matters,  has  not  been 
determined.  Tests  applied  seem  to  indicate  that  the  newly  formed 
bast  contained  less  of  tannic  matters  than  the  earlier  formed  parts. 
Stone  cells  of  large  size,  and  often  quite  irregular  in  shape,  were 
scattered  without  order  through  all  but  the  youngest  portions  of  the 
bast  layer.  It  has  already  been  shown  that  stone  cells  occur  in  the 
middle  bark  as  well. 
The  bark  of  the  specimens  examined  contained  considerable 
starch,  the  tangential  rows  of  large  cells  occurring  at  frequent  and 
rather  regular  intervals  in  the  bast  layer,  being  especially  rich  in 
small  grains. 
The  medullary  rays  were  seen  to  be  narrow,  being  but  one  cell 
broad,  and  in  longitudinal-tangential  section,  appearing  as  a  fusiform 
