Quite early
in
the
development
of
plant
chemistry,
it
was recognized
that
in
the
woody
(“lignified”)
portions
of
plants, such
as
stalks, stems,
cobs,
hulls, leaves,
trunks
of
trees
and
shrubs,
there
is
associated with
the
cellulose
and
the
other carbohydrates
a
substance, or
a
group
of
closely
related
and
possibly isomeric
substances,
which
has
been
designated
“lig-
nin.”
Schulze
(264)
is
generally
credited
with
having introduced
this
term
into
chemical
literature, although
according
to
Czapek
(30)
it
had
previously been employed
by de
Candolle