this way, it might be supposed the investigation of the diet of
animals and plants would render clear. Our hopes of distinguishing the
one group from the other by reference to the food on which animals and
plants subsist are, however, dashed to the ground; and the diet
question leaves us, therefore, when it has been discussed, in the same
quandary as before.

Nevertheless, it is an interesting story, this of the nutrition of
animals and plants. A large amount of scientific information is to be
gleaned from such a study, which may very well be commenced by our
having regard to the matters on which a _green_ plant feeds. I
emphasize the word "green," because it so happens that when a plant
has no chlorophyl (as green color is named in the plant world) its
feeding is of diverse kind to that which a green plant exhibits. The
mushroom or other fungus may be taken as an illustration of a plant
which represents the non-green race, while every common plant, from a
bit of grass to an oak tree, exemplifies the green-bearing order of
the vegetable tribes.

Suppose we were to invite a green plant to dinner, the _menu_ would
have to be very differently arranged from that which would satisfy a
human or other animal guest. The soup would be represented for the
plant's delectation by water, the fish by minerals, the joint by
carbonic acid gas, and the dessert by ammonia. On these four items a
green plant feeds, out of them it builds up its living frame. Note
that its diet is of inorganic or non-living matter. It derives its
sustenance from soil and air, yet out of these lifeless matters the
green plant elaborates and manufactures its living matter, or
protoplasm. It is a more wonderful organism than the animal, for while
the latter can only make new protoplasm when living matter is included
in its food supply, the green plant, by the exercise of its vital
chemistry, can transform that which is not living into that which is
life-possessing.

The green plant in other words, raises non-living into living matter,
while the animal can only transform living matters into its like. This
is why the plant is called a constructive organism, while the animal
is, contrariwise, named a destructive one. The result of the plant's
existence is to build up, that of the animal's life is to break down
its substance, as the result of its work, into non-living matter. The
animal's body is, in fact, breaking down into the very things on which
the green