?52  Structure  of  Bye-Woods,  { jify'xfso!"™- 
points  (finer  than  those  of  the  Brazil-wood)  of  0'o8  mm.  diameter. 
The  medullary  rays  occur  in  scattered  patches  as  remarkably  delicate 
lines.  The  body  of  the  wood-fibre  is  hard  and  black-red  j  the  paren- 
chymous  bands  are  unbroken  and  cherry-red. 
The  tangential  incision  plane  does  not  disclose  any  remarkable 
peculiarity  in  structure,  even  under  the  lens.  Here  and  there  are 
single  widened  ducts.  Very  characteristic  are  the  longitudinal  stripes 
on  the  radial  incision  plane;  they  are  visible  without  the  lens.  They 
originate  in  the  parenchymous  zones;  4  to  6  of  them  equal  i  mm. 
The  medullary  rays  appear  as  bright  small  bands  of  unequal  width. 
Under  the  lens,  a  slight  cross  marking  is  observed  on  them.  The 
ducts  appear  in  spots  as  dark  and  shining  longitudinal  lines. 
6.  Old  Fustic  (Madura  tinctoria). — The  cross  sections  show  medul- 
lary rays  without  use  of  lens.  The  annual  rings  fail  completely. 
This  forms  the  most  material  difference  between  it  and  the  Madura 
aurantiaca.  In  the  thick  dirty-brown  background,  partly  isolated, 
partly  more  or  less  removed,  are  besprinkled  band-like  compact  paren- 
chymous patches.  (See  Fig.  8.)  The  bands  appear  to  be  indented. 
The  ducts  are  completely  filled  with  parenchyma,  and  therefore  the 
duct  openings  are  not  visible  under  a  microscope. 
The  tangent  section  shows,  in  a  brilliant  background,  innumerable 
regularly  scattered,  dark,  short  screaks  (medullary  rays),  and  tolerably 
broad,  somewhat  bent,  ochre-yeiiow  lines,  which  originate  in  the  ducts 
filled  with  parenchyma.  On  the  radial  section  the  medullary  rays 
appear  as  pale  cross  lines,  about  O'l  to  0*25  mm.  in  width.  Under  the 
lens,  they  reveal  6  to  20  delicate  lines,  originating  from  the  separate 
cell  series.  On  the  longitudinal  section  the  ducts,  under  the  lens^ 
appear  as  if  filled  with  yeilow-colored  scales,  which  are  lustrous. 
The  wood  of  the  Madura  aurantiaca  is  readily  distinguished  from 
that  of  old  Fustic  by  the  well-defined  annual  ring,  also  by  the  light  and 
not  ochre-yellow  color  of  the  parenchymous  mass,  and  its  much  finer 
structure.  The  parenchymous  patches  are  more  oblique  in  position, 
and  in  the  spring  consist  of  ducts  filled  with  parenchyma,  etc. 
7.  Barberry  (Roots  of  the  Berberis  vulgaris). — Intense  lemon-yel- 
