Kansas City journal. [volume] (Kansas City, Mo.) 1897-1928, 1897-04-04
The Green Color of Plants.

D. 7. MacDougal in Harper's for April
The yearly miracle of the appearance of
innumerable shades and hues of green in
awakening vegetation eXertS a mysterious
influence, amounting to a fascination. over
the human race-a fascination made strong
by the inherited experience of untold gen.
er3tions of forest-dwelling ancestors,
reaching backward across the entire pres
en-: geological period, and which grows IN
intensity as We creep from the creation 10
the Millennium
Our vague and emotional inherited in
tereSt in the annual revivification OF the
vegetable world becomes vividly intense
and direct, however. when IL is learned
that the universal blush of green is due
TO the most important coloring substance
in the world-chlorophyl. 1t is literally
true that the existence of every living
thing on the face of the globe Is ultimately
dependent upon the activity of plant green
The action of chiorophyl may best be
understood when its physical properties
are demonstrated In order to do this q
solution of the substance is obtained by
placing a gramme of chopped leaves of
geIanium or grass in few cubic cent?
meters of alcohol for an hour The solu-
ton will be a. bright green color, and when
the vessel containing it is held in such a
manner that the sunlight Is reflected from
the surface of the liquid il will appear
blood red, due TO its property of fuoreS-
cenct-that OF changing the wave lengths
of the violet end OF the spectrum in such
a manner as TO make them coincide with
those of the red end It is by examination
of light which has passed through a Soiu-
tion of chlorophyl- however, that the great
est insight into its physical properties may
be obtained If such a ray is passed
through prism and spread upon q screen
il may be seen that there are several in
teryals or dark bands in the spectrum The
rays which would have occupied these
spaces have been absorbed by the chloro-
phyl and converted into heat and other
forms of energy. This energy is directly
available to the protoplasm containing the
cElcfphyL As necessary concomitant Of
its properties, chlorphyl is usually only TO
be found in organs exposed to the light
II would be rot only useless but dangerous
elsewhere, as it disintegrates in darkness
into substances hurtful 10 the organism
II is found in greatest quantity in leaves.
in layers of special cells beneath the epi-
dermis II is not distributed throughout
thu entire cell. but occurs in the masses OF
protoplaSm which the botanist terms chic
roplaSts. The chloroplastS are sponge-like
structures and the chiorophyl is to be
found in solution IN an oil in the interstices
of the protoplasnic sponge
ChIorophyl is an extremely complex sub
stance, and correspondingly unstable
Hence. as soon as the chemist extracts IL
from the plant in the attempt to make an
analysis, disinteEration sets in and he Is
no longer dealing with chlorophyl- but
with the substance derived from II oy de-
ture and activity of plant-green has been
in progress more than century. yet its
exact chemical composition Is unknown.
The beautiful and striking colors of au-
tumnaI foliage are due in greater part to
the substances formed by the disintegra-
ton OF chlorophyl- The many thousand
tints of green leaves are due to 4 number
of causes In some instances the outer
layers of the cells OF the leaf. or merely
the walls of the cells. may contain color
ing matter The number and size of the
chioropIasts. and consequently the amount
of chioTophyl. may be greater in some
leaves than in others. Besides the chloro-
plasts may be moved about in the cell and
their distance from the surface of the leaf
altered. or they may be placed in lines
or broadside to the surface
In this manner the infinite and elusive va
riations of color, so fascinating to the lover
of nature. are produced in vegetation. The
color of leaf may vary momentariIy
the entire day. as. indeed, does
puzzled artist.