3  36  North  A  merican  Conifer cz.  { Am j^ifs^1^ 
which  were  sclerotic ;  interior  to  this  a  rather  thick  cortical  par- 
enchyma, composed  wholly  of  thin-walled  cells,  many  of  which 
are  rich  in  tannin  and  resin,  and  in  which  occur  secretion  reser- 
voirs of  the  usual  character,  and  also  some  irregular  lacunae  con- 
taining air;  a  bast  layer  composed  of  smaller  cells,  many  of  them 
containing  tannin,  all  thin-walled,  and  arranged  more  or  less  dis- 
tinctly in  radial  rows ;  a  cambium  zone,  also  containing  tannin, 
and  a  xylem  cylinder  consisting  of  tracheids  similar  to  those  of  the 
other  pines;  medullary  rays  which  contained  considerable  tannin, 
and  scattered  secretion  reservoirs,  containing  oleoresin  and  sur- 
rounded by  cells  which  also  contained  tannic  matters.  Many  of  the 
tracheids  and  medullary  ray  cells  contained  oleoresin,  as  did  also 
many  of  the  parenchyma  cells  of  the  bark. 
CHEMICAL  COMPOSITION. 
The  leaves,  stem  bark  and  root  bark  from  a  tree  of  Pinus  sylvestris 
grown  in  the  vicinity  of  Philadelphia,  and  collected  in  November, 
have  been  examined  for  percentage  of  tannin  and  ash,  with  the  fol- 
lowing results  : 
Moisture. 
Ash  in  abso- 
lutely dry 
substance. 
Tannin  in 
absolutely  dry 
substance. 
7'50 
3 '46 
6*84 
10*07 
2*63 
16*91 
10*04 
2*66 
I3'i7 
The  ash  of  the  leaves  contained  potassium,  iron  and  calcium  car- 
bonates, phosphates  and  sulphates. 
The  ash  of  the  stem  bark  was  similar  to  that  of  the  leaves, 
with  the  exception  of  the  iron.'  The  ash  of  the  root  bark  contained 
the  same  compounds  that  were  found  in  the  leaves. 
The  tannin  and  other  constituents  of  an  acid  character,  contained 
in  this  pine,  have  been  studied  by  a  number  of  European  investiga- 
tors, notably  Kawalier  [Sitzber.  der  K.  Akad.  zu  Wien,  11,  344, 1853), 
and  an  appendix  to  this  shortly  after  by  Rochleder  and  Schwarz. 
ECONOMICS- 
This  is  a  valuable  timber  tree,  much  used  for  lumber  and  ship- 
building in  the  countries  in  which  it  grows.    Its  heart  wood  is  red- 
