the tree will grow a house around him that will be totally unlike the
rest of the branches or leaves. That is an "oak gall." If you
carefully cut a green one open you will find the bug in the centre or
in the case of a dried one that we often find on the ground, we can
see the tiny hole where he has crawled out.

Did you ever know that some kinds of ants will wage war on other kinds
and make slaves of the prisoners just as our ancestors did in the
olden times with human beings? Did you ever see a play-ground where
the ants have their recreation just as we have ball fields and
dancing halls? Did you ever hear of a colony of ants keeping a cow? It
is a well-known fact that they do, and they will take their cow out to
pasture and bring it in and milk it and then lock it up for the night
just as you might do if you were a farm boy. The "ants' cow" is a
species of insect called "aphis" that secretes from its food a sweet
kind of fluid called "honey dew."

The ten thousand things that we can learn in nature could no more be
covered in a chapter in this book than the same space could cover a
history of the world. I have two large books devoted to the discussion
of a single kind of flower, the "orchid." It is estimated that there
are about two hundred thousand kinds of flowers, so for this subject
alone, we should need a bookshelf over a mile long. This is not stated
to discourage any one for of course no one can learn all there is to
know about any subject. Most people are content not to learn anything
or even see anything that is not a part of their daily life.

The only kind of nature study worth while is systematic. It is not
safe to trust too much to the memory. Keep a diary and record in it
even the most simple things for future reference. All sorts of items
can be written in such a book. As it is your own personal affair, you
need not try to make it a work of literary merit. Have entries such as
these:

First frost--Oct. 3rd

First snow--3 inches Thanksgiving day

Skating--December 3rd

Weather clear and bright on Candlemas day, Feb. 2nd and
therefore ground-hog saw his shadow

Heard crows cawing--Feb. 18th. Last year--Jan. 26th

Saw first robin--March 14th

Last snow--April 28th

There is scarcely anything in nature that is not interesting and in
some way useful. Perhaps you will say "How about a bat?" As a matter
of fact a bat is one of our best friends because he will sp