ircle; at the end of fifteen years some of these
circles acquire a diameter of fifteen to twenty feet or more. These
are known as fairy rings. Before science dispelled the illusion they
were believed to have been the work of witches, elves, or evil spirits,
from which arose the name.

Several kinds of lichens and mosses and the like, growing on the barks
of trees, fence boards, and low ground, spread slowly in the manner
of fairy rings.

However, the spreading is not always a slow, creeping process, for
sometimes these low plants spread over an incredible distance in a
short space of time. In some instances they appear suddenly almost
anywhere, and at any season of the year. They are all minute and exist
in countless numbers, and their devices for securing wide dispersion
are so various as to entitle them to first rank in this respect. Some
send off spores with a sharp puff, as if shot from a little gun. Some
of these spores float on water, and some are sticky and thus gain
free rides. It is not at all improbable that some are carried by the
winds across oceans and continents.

It is well known that many of the lower species of plants are more
widely distributed over the earth than most of the higher plants.
Every cloud from a ripe puffball consists of thousands of spores
started on the wings of the wind for an unknown journey. Their habits
are not past finding out, but to examine them a person needs a good
microscope. Most of them have no special common name, and with one
or two exceptions further mention of the mode of distribution of this
fascinating portion of plant life cannot here be made.

In our botanic garden was planted a patch six feet across of what
is known as Oswego tea, bee balm, or red-flowered bergamot, an
interesting plant with considerable beauty. It grew well for a year,
the next year it failed to some extent, and on the third most of the
plants died, or nearly died, excepting the spreading portion all
around the margin. This is a fairy ring of another type, and represents
a very slow mode of travel. As further illustrations of this topic
study common yarrow, betony, several mints, common iris, loosestrife,
coreopsis, gill-over-the-ground, several wild sunflowers,
horehound, and many other perennials that have grown for a long time
without transplanting.

The roots of plants are seldom much observed, because they are out
of sight. In soft ground the roots of the common or black locust extend
f