appropriate, many fishes having a hard,
protecting coat of shining scales. These scales, besides being beautiful
and useful, are interesting in another way, for we know that they are
only modified hairs, growing from the skin as hairs grow but having
their form and size developed in special ways to serve their purpose.
Scales and feathers are only another form of hairs.

Many interesting stories of fishes can be told or read to the children,
and among other things they can learn about the swim-bladder, the large,
strong air-sac, which can be compressed or distended at pleasure, making
the fish lighter or heavier and enabling it to rise to the surface of
the water or sink to the bottom. In Nova Scotia, where many codfishes
are caught, the swim-bladders are called sounds, and are cooked as a
delicacy.

In the spring of the year we eat the roe of fish, which is nothing more
nor less than fish eggs. Wherever shad are used, the children will be
familiar with the shad roe; and in the South mullet roes are universally
used. The people there dry them in the sun, and the children
particularly are very fond of them. The Russian caviare is the eggs of a
species of fish, and is considered a great delicacy by some people.

Where do these eggs come from? The fish market or the kitchen on fish
day will answer the question. The child who is privileged to pass part
of the summer at the seashore where fishermen ply their trade will have
ample opportunity to know, as will the child who goes fishing in any
brook or pond and is allowed (as he always should be) to clean and cook
the fish he has caught. Also the smelts, which are cooked whole, only
the intestines being removed through a hole near the gills, will answer
the question.

[Illustration: THE OVARY OF A FISH]

The eggs of the fish are contained in a sort of double pouch or sac,
shaped something like an old-fashioned silk purse. These sacs open into
the intestine near its exit. They are the ovaries of the fish. From the
inside of each ovary the tiny eggs, or ova, grow, just as the ovules
grow in the plant ovary or seed-pod. At first they are a part of the
ovary; later they grow larger and fall loose, until the ovary is filled
with them. The ovary is always inside the fish. It is there when the
fish is born, and even then there are the tiniest hints of ova in it.
But the ova do not grow large until the fish is mature; they wait until
the fish has developed its strength, its bone