stances.

These examples only serve to recall to mind what every boy or girl
knows and has known ever since he can remember--that most animals
move about whenever they want to, or whenever other animals will let
them.

2. Some animals catch rides in one way or another.--Some small animals,
like lice, ticks, and tiny spiders, walk slowly and only for short
distances. If, because of scarcity of food, they are suddenly seized
with the desire to move for a long distance, what are they to do?
On such occasions ticks and lice watch quietly the first opportunity,
catch on to the feet of birds or flying insects or other animals which
may happen to come their way, and, like a boy catching on to a farmer's
sleigh, ride till they get far enough, then jump off or let go, to
explore the surrounding country and see whether it is fit to live
in. If for some reason a spider grows dissatisfied and wants to leave
the home spot, she climbs to the top of some object and spins out
a fine, long web; this floats in the air, and after a while becomes
so long and light that the wind will bear the thread and the spinner
for a considerable distance, no one knows how far. These facts about
lice and spiders show how wingless insects can go long distances
without wings of their own.

How is it with plants? The woods, fields, marshes, roadsides ever
abound with interesting objects provided with strange devices
waiting to be studied by inquisitive girls and boys in and out of
school, and this finding out of nature's puzzles is one of the deepest
pleasures of life.

How quickly a mould attacks and creeps or spreads through a basin
of berries every one knows. The mould is as much a plant as the bush
that produced the berries; it comes from a small spore, which takes
the place of a bud or sprout or seed. The decay of a tree begins where
a limb or root has been injured, and whether the timber is living
or dead, this decay results from the growth of some one or more low
forms of plant life which enter the timber in certain places and slowly
or quickly penetrate and affect other portions more or less remote.

CHAPTER II.
PLANTS SPREAD BY MEANS OF ROOTS.

3. Fairy rings.--Several low forms of plant life, such as _Marasmius
oreades_, _Spathularia flavida_, and some of the puffballs, start
in isolated spots in the grass of a lawn or pasture, and spread each
year from a few inches to a foot or more in every direction, usually
in the form of a c