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the upper pair is hard and horny, and serves to protect the softer membranous pair when not in use. In other tribes the wings resemble the finest lace; and in the butterflies and moths they are covered with a mealy substance, which examination under a lens shows to be composed of the most delicate scales, differing in form, in size, and in colouring, and giving to some of them the gorgeous metallic tints for which they are so remarkable.

"The grand and characteristic endowment of an insect," says Professor Owen, "is its wings. In no other part of the

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animal kingdom is the organization for flight so perfect, so apt to that end, as in the class of insects. The swallow cannot match the dragon-fly (Fig. 58) in flight. This insect has been seen to outstrip and elude its swift pursuer of the

feathered class: nay, it can do more in the air than any bird; it can fly backwards and sidelong, to right or left, as well as forwards, and alter its course on the instant without turning."

From the great importance of the wings, and from the modifications in their structure, they become naturally the basis for classification, and enable us to arrange the various insect tribes in nine Orders. To each of these our attention may now be briefly directed.

ORDER I.-BEETLES.

COLEOPTERA (SHEATH-WINGED).

AMONG the various tribes of beetles constituting the present order, very great difference exists, even in our native species, in size and colouring. The great Water-beetle is sufficiently powerful to play the tyrant of the pool in which he lives, and even to attack and overcome small fishes. Others, again, are so minute, as to live in the perforations they make in the timber of our dwelling-houses, and thus to escape detection by ordinary observers. Among the latter may be mentioned those little beetles (Fig. 59), to which vulgar superstition has given the name of "Death-watch."

"The solemn Death-watch click'd the hour she died."-GAY.

This sound, which is only the call of the insect to its companion, so exactly resembles the ticking of a watch, that Mr. R. Ball, by placing his watch to the wainscot which the little

beetle frequented, has caused the insect to respond to its ticking.

In many beetles, the wing-cases (elytra) are united together, and, as wings could not be used, they are not given. In the glow-worm (Fig. 60, 61), an insect not found in

Fig. 59.
PTINUS (MAGNIFIED).

Fig. 60.
MALE GLOW-WORM.

Fig. 61. FEMALE GLOW-WORM.

Ireland, the female, being soft and wingless, does not seem to belong to the present order; but the male is possessed of wing-covers, and of expansive wings, by means of which he is enabled to shape his course to the light displayed by the more stationary female.

The "droning-flight" of the Dor-beetle, heard in the twilight of the summer-evening's walk, is a sound with which every one is familiar; and equally well known is the manner in which the creature startles us from our reveries by striking against our faces. It is from this circumstance, and not from any absence of the sense of vision, that its common epithet, the "blind-beetle," has been derived. To this family belongs the sacred beetle of the Egyptians (Fig. 62), whose image remains sculptured on many of their obelisks

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and other monuments. It still attracts the attention of travellers, from its habit of collecting and rolling about a ball of dung, in which it deposits an egg.

As a contrast in habits to this beetle, may be mentioned the Cicindela (Fig. 63), which is regarded as one of the tigers of the insect tribes. Its colour is a golden green, with

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white or yellow spots, and it appears particularly rich when the insect is running rapidly along in the bright sunshine of a summer's day. Other species carry on their operations so as to escape our notice. Thus the Nut-weevil (Fig. 64), with her long horny beak, drills a hole through the shell while it is yet soft, deposits an egg in the nut, and, at the same time, furnishes her future offspring with a house for its defence, and food for its support.

ORDER II.-CRICKETS, LOCUSTS, ETC.

ORTHOPTERA (STRAIGHT-WINGED).

THIS division includes in it the cockroaches, crickets, grasshoppers, and

locusts, and those very strange-looking creatures, from tropical countries, which have been by common consent, named walkingsticks' and 'leaf insects.' Some species of the latter, which we see in our museums, have the wing-covers of so bright and fresh a

green, that we can

with difficulty persuade ourselves we

are looking on an

Fig. 65.-LEAF-INSECT.

insect; while others present a no less striking resemblance to the colour of the leaf, and its delicate network, as it lies on the ground in its withered state (Fig. 65).

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