swifter and stronger. One watched by Leeuwenhock
was chased by a swallow in a menagerie
a hundred feet long. The dragon-fly distanced
the swallow and beat him at the end. A dragon-fly
once flew on board ship at the least five hundred
miles away from the nearest point of land,
without, so far as could be seen, stopping to
rest, though some rest, one would think, it must
have had. From the centipede to the dragon-fly,
from the wild horse to the sloth, we pass
through a pretty wide range of differences.

The wings of insects are very interesting
objects, both to look at unassisted, and with the
microscope. The wings of the house-fly are
found to be covered with minute stiff short
hairs; the black network of lines that we see
in them are elastic horny tubes, over which the
membrane is stretched like the silk of an umbrella
over its ribs. Bees have a very curious mode
of strengthening their flight, in the shape of
hooks and corresponding doublings on the edges
of their wings, so that when they are flying,
these are kept expanded by even extra aids to
the elastic ribs and tightened membrane. Who
would have thought of a bee hooking and eyeing
himself out in that manner! All sorts of theories
have held ground successively, respecting the
feet of flies. First they were suckers, and they
walked by means of exhaustion and atmospheric
pressure; then they were grappling irons, and
they hooked themselves on to microscopic
inequalities by means of invisible hooks; then
they were glue pots and exuded a natural gum,
which gummed the insect at every step; now we
believe they are assumed to be all three: claws,
or spines, to hook; pads, or cushions, to preserve
them from abrasion (these pads were the original
suckers); hairlets as sucking disks, that exude
a certain moisture,—all these hypotheses are
found to be true, as always happens in cases
when truth unrols itself in sections.

The scales on the wings of insects are a world
in themselves. The little bristle tail which
leaves a thick dust on your finger, though touched
never so lightly, leaves in that dust a mass of
metallic scales of all shapes. Oval, heart-shaped,
round, elliptic, long and narrow, shovel-shaped,
they lie under the microscope like a collection
of fairy toys, all made out of gems. The sugar-
louse has oval or shovel-shaped scales, set on to
a stalk and arranged like a fan; the five-plume
moth of the summer meadows has them willow-
leaved in shape, sometimes singly pointed, but
generally notched with two, three, or four
notches; the six-spot burnet moth has them
lustrous but opaque; the blue butterfly, shaped
like a battledore; the buff-tipped moth has
large scales like a fan; the magnificent emperor
has them triangular; while some have them
fringed, some pear shaped, and others corrugated,
but all overlapping each other, or tiled. The
diamond beetle is the most splendid fellow of
the lot. He has a row of precious stones in his
flat transparent scales that irradiate the whole
field with their gleaming glory. Those precious
stones are set on to broad bands of black velvet,
velvet and jewels alternating in stripes in the
most regal and enchanting manner. Few objects
are so beautiful as the scales of the diamond
beetle, with their royal richness and burning
glory.

Then what strange projections of science we
find! We have already spoken of the mower's art
typified in the mollusk's tongue, now we come
to the air-pipes of insects, and the best modes of
strengthening them. Being marvellously thin,
they are consequently very liable to injury; wherefore
they are lined, just as we line our gas-pipes,
with a delicate coil of springs wormed within them
in close spirals. This exquisite thread is wound
round and round, like the most intricate and
attenuated watch-spring, and keeps the air-pipe
distended, while it affords the greatest amount
of strength and protection compatible with the
space and design. This coil has the strange
quality of not being continuous, and as if cut
out of an infinite length; but is pierced as if
cut out of a plate that was not long enough, and
so has to be joined and added to every now and
then. The joinings are quite visible under the
microscope; but no theory that we know of has
been yet started to explain this strange
parsimonious freak of nature. All small insects
have this watch-spring, or gas-pipe lining to
their air-tubes; but they do not depend wholly
on those air-tubes. They have breathing holes,
or spiracles as well, all over their bodies—oval
disks sunken into little pits—black, with a white
centre. The entrance to the spiracles is
variously defended. Some open with a trap-door;
some are covered with a fine gauzy net; some
are protected by a sieve, as in the house-fly;
others by a filter, as in the daddy-longlegs;
others, again, are true colanders, as in the grub
of the cockchafer; but all have their spiracles,
or breathing-holes, and all are defended against
dust and dirt by some such contrivance as we
have spoken of.

If but everything about them was as harmless
as wings and breathing-holes! Unfortunately
for us, our admiration has often to take a
rueful turn, and, warm from our delight in
jewelled scales and cunning mechanism, we turn
to other organs which excite anything but
pleasure. The sting of the bee, for instance, is not
a very charming thing to contemplate, with the
possible chance of a personal acquaintance. That
sting is composed of a pair of lancets kept in a
sheath until the time of action, serrated or
saw-toothed the wrong way; so that when they have
once plunged themselves into anything, they are
not very easy to withdraw, as the teeth point
backward, and keep fast but invincible hold. At
the base of these lancets is the huge poison-bag,
which gives the sting its venom, and does all the
real mischief. The horse-fly, with the brilliant
metallic colours, red, blue, and scarlet, painted
in broad bands round his large eyes, has a
tremendous array of lancets; gnats with their eyes
like great globes of black velvet studded with
gold buttons, have six lancets of various forms,
one-sixth of an inch long, and furnished with a
poisonous fluid to add to their power; the biting
apparatus of the abominable bug is a long spit