flat. The shell is on
the back, nearer the tail than to the head. It has a spiral twist, as
is shown in the picture.

9. The snail's body, where it touches the ground when he moves, is
called the foot. When he moves, the head reaches forward first and
takes a firm hold, then the other parts come forward in turn, the tail
last.

10. The snail can not crawl over a dry place; so, when he moves, a
thick fluid comes out of his foot, moistening the surface as he passes
along.

11. As he must be saving of this fluid, in dry weather he stays at
home most of the time, and comes out only when it is wet enough to
crawl about.

12. When the cold weather comes, the snail crawls away to some quiet
place, usually under a log or a stone, draws himself into his house,
makes a door to keep out the cold, and goes to sleep until spring.

LESSON LI.

_THE FLY AND ITS WAYS._

[Illustration]

1. Here is one of our friends that we know very well--the common
house-fly. It is here drawn large on purpose, so that we can better
see how it is made.

2. The fly is an insect. Its body is divided into three parts; and it
has three pairs of legs. Upon its head are two large eyes, each of
which is made up of about two thousand small eyes. When we look
through a glass that makes things look large, we can see and count
these little eyes of the fly.

3. Its feet are made in such a way that they will stick wherever it
places them, so that it can crawl up the walls of the house, or on the
ceiling, with its back down.

4. The fly's wings are light and thin, and made up of fine network. It
has no jaws or teeth; and, instead of lips, it has a tube, or trunk,
through which it sucks up its food, as we can suck milk through a
straw.

5. When a fly lights on a lump of sugar, it puts out its trunk, and
lets fall a drop of fluid, which is clear like water. This moistens
the sugar, and then the fly sucks it up.

[Illustration: A Fly's Leg, magnified.]

6. The fly keeps himself very clean. After each meal it brushes its
head, first on one side, and then on the other, with its first pair of
legs. Then it will rub the two legs together to get off the dirt.

7. The fly lays its eggs in the kind of food its young can eat. In a
short time a little white grub hatches out, which does nothing but eat
until it is of full size.

8. Then its skin becomes hard, and shrinks. It lies still, and does
not eat anything for several days; but, inside its h