The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1897-10-23
UNIVERSITY EXTENSION
FIRST OF A SERIES OF LECTURES BY
JOHN NJ. COULTER.
Talked on the Relation of Plants to
Food 49, Large Audience
Present.

John NJ Coulter, professor of botany of
Chicago University, last night delivered the
first of a series of lectures arranged by
the University Extension Club of Indian
apolis. The series will deal with plants in
their environment, Professor Coulter's first
topic being the Relation of Plants to
Food" The lecture was given at the First
Baptist Church to a large audience. Pro-
fessor Coulter said in part:
THE study of plants has been revolu-
tionized in the last few years. Once it was
a study of names, then a study of struc-
lures, chiefly by means of the microscope.
Now it is becoming a study of living organ
isms at work. Plants hold a most con-
spicuous position in any view of nature.
They form the most striking features of
the lanscape and should be studied in this
mass relation. The purpose of this course
of lectures is to gain this large view of
the plants that an intelligent view may
be had of nature. In this way every land
scape has its significance. The subject for
the evening concerns probably the most i'm
portant relation of plants to their environ
ment. 1t deals with the relation of
the plants to the food which they
need. A general clew to the problem
may be obtained by study Of the compost
ton of plants. We find that certain ele-
of all plants. Therefore we are safe in con-
GLIDING that these elements must enter into
the food. 1t is observed also that all the
food of plants must be in the condition of
either gas or fluid This constitutes one
great difference between plants and ami
mails. the latter of which are able to take
in solid particles. On the basis of food
terial plants may be divided into three
great groups
GREEN PLANTS.
"Green Plants-These are the plants COM
monty thought of and about the only ones
generally noticed. By virtue of the green
which is their characteristic leaf color they
are able to do work impossible to other
plants or animals. The Importance of this
work may be known from the fact that
it is the only process that changes dead to
living matter. Therefore, upon this pro-
cess the whole world lives. The raw ma
terials used are carbon dioxide water and
nitrogen salts. These are waste substances
from animals and plants and are wastes
because they cannot be broken up by ordi-
nary processes. However, by virtue of the
green color these plants are able to break
up these substances and re-combine them
into living substances. The active agent
in this process is the light which strikes
| through the green color and some of its
| rays are changed into form of energy
| which the living protoplasm uses in accom-
| plishing the work. From this standpoint
| study of the leaves of plant becomes not
| the study OF dead form but the study of
| an organ seeking to relate Itself most IA
| vorably to light. Instead of studying the
| endless details in connection with the leaf
| the real significance of the organ comes
| out only in a study of it's endeavor to put
| Itself into the most favorable condition to
secure light.
''Parasites-There are certain plants
which are not able to make their own food
| by virtue of not having the green color.
| AS a consequence they must depend on
| food already made, which they secure from
| the living bodies of plants and animals.
They either send down suckers into the liV-
| ing bodies to absorb nourishment or the
whole body of the parasite may burroW
INTO the tissues OF the most Such organ
| isms often become of very great economic
| Importance on account of their destruction
| of our valuable crops and animals. The
wheat rust is an example of a tremendous
| ly destructive parasitic plant The govern
ment is probably spending more money
| upon this phase Of botany than any other,
| in the hopes of discovering ways by which
| these so-called plant diseases may be pre-
| vented. When it is remembered, also, that
bacteria are parasitic plants, and that
many of them are the active causes of our
worst, contagious diseases, 1t becomes evil
| dent that. the parasites are of immense
| practical Importance. 1t is interesting
| fact that all these parasites are degenerate
green plants and that the parasitic habit
| has been thing of slow development,
MUSHROOMS AND LICHENS.
"Saprophytes-These plants are not green,
nor do they live upon living animals or
plants, but they obtain their food from the
dead and decaying bodies of other organ
isrns. The mushroom is a familiar exam
pie of this group, living, as it does, upon
decaying leaves and stems. The common
| molds, also, which we find growing on our
preserved fruits, old leather, ETC., are other
illustrations. The relation of these plants
not being to light, they very frequently
grow in the dark and are the only forms
of plants to be found in caves and cellars
So far as they are of any Importance they
may be regarded as ScaVangerS-haStening
the decomposition of dead bodies.
Another group of plants are known as
carnivorouS because they have become able
to capture insects as food. Various aston
fishing devices have been developed which
have been likened to steel traps and pit
falls. These captured insects are often di-
geSted just as they would be in the stomach
of an animal. These plants, however, are
ordinary green plants, which have been
driven to obtain such food because of the
therefore, there are three classes of organ
sms which differ from each other in con-
structive power, viz, green plants, plants
that are not green, and animals Of these
green plants have the greatest constructive
power and animals the least"
Professor Coulter Will on next Friday
night give the second lecture of the series
He will talk on the dependence of Plants
Upon Each Other"