y seemed to be having a
beautiful and breathless time. "Do you know of a family around here,"
called the guide, "whom nobody likes?"

"I do," replied Mrs. Reece, laughing and slapping the side of her face.
"They are just like some people, nagging, annoying, and numerous."

"Do any children here," called Ben Gile, for the third time, "know of a
family nobody likes? For the child who guesses I have a pocket-knife."

"The Smiths!" shouted Peter. "My father says Mrs. Smith is always
quarrelling with the choir."

"Hush!" said Mrs. Reece, seeing danger ahead. "Ben means a family right
here on the piazza."

The children looked at one another, and then Jack turned shrewdly to the
guide. "I guess, sir, it is mosquitoes and flies."

"Good boy, and here's the knife."

Jack thought he had never seen such a wonderful knife. It had three
blades, a corkscrew, a file, and a pair of scissors, and to this day
Jack has that knife.

"Come," said Mrs. Reece, "let us all sit down for a few minutes while
Lizzie is getting supper ready inside."

"How many wings," asked Mrs. Reece, "has a fly?"

"Four," answered Jimmie.

"No," corrected the guide; "a real fly has only two wings. In the place
of the second pair they have queer little knobbed rods which are called
balancers--something like the out-riggers on your scull, Jim. These
steer and steady the fly's body."

"What makes a fly bite?" asked Hope.

"They do not bite, child. A beetle or a grasshopper can really bite,
because beetles and grasshoppers have heavy, horny jaws, toothed on the
edge, with which to do it. But a fly has fine, sharp-pointed jaws. With
these needlelike jaws they pierce a hole in the skin, then with a tiny
sucking-beak, made by the rolled lower lip, they draw up the blood
through this opening."

"I wonder whether any little girl here knows why flies should not be
allowed in the house?" asked Mrs. Reece. No little girl did know
anything except that their mothers were always driving flies out, and
that these creatures buzzed and were a nuisance. "Do tell them," said
Mrs. Reece.

[Illustration:
_A._ House-fly.
_B._ A grown-up mosquito, two larvae, and a pupa.]

"Well," said the guide, "the fly is such a little acrobat it can crawl
up the steepest and most slippery wall and walk upside down or right
side up with the greatest ease. Perhaps some day you can make a fly keep
still long enough so that you can look at its foot. At the end of the
foot are two