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But the fabric of their bodies, their instruments of motion, and the organs by which they take their food, are materially changed. This change of structure, though the animals retain their identity, produces the greatest diversity in their manners, their economy, and the powers of their bodies. In the caterpillar state, these animals are extremely voracious, and, in many instances, acquire a greater magnitude than they possess after transformation; but they are incapable of multiplying their species, and of receiving nourishment from the same kinds of food. Besides, many caterpillars, previous to their transformation, live even in a different element. The ephemeron fly, when in the caterpillar state, lives no less than three years in the water, and extracts its nourishment from earth and clay. After transformation, this animal seldom exists longer than one day, during which the species is propagated, and myriads of eggs are deposited on the surface of the water. These eggs produce worms or caterpillars, and the same process goes perpetually round.
The second order of insects, denominated hemiptera, have likewise four wings. But the upper pair, instead of being hard and horny, rather resemble fine vellum. They cover the body horizontally, and do not meet in a direct line, forming a ridge or suture, as in the beetle tribe. The whole of this order are furnished with a proboscis or trunk for extracting their food.
This order comprehends several genera or kinds, some of which I shall mention in a cursory manner. -The blatta, or cockroach, is an animal which avoids the light, and is particularly fond of meal, bread, putrid bodies, and the roots of plants. It. frequents bakers shops and cellars, and flies the approach of danger with great swiftness.-The head
of the mantis, or camel-cricket, appears from its continual nodding motion, to be slightly attached to the thorax. This insect is regarded by the Africans as a sacred animal; because it frequently assumes a praying or supplicating posture, by resting on its hind feet, and elevating and folding the first pair. The gryllus comprehends a number of species, some of which are called grasshoppers, others locusts, and others crickets. The caterpillars of the grylli, have a great resemblance to the perfect insects, and, in general, live under ground. Many of these insects feed upon the leaves of plants. Others, which live in houses, prefer bread, and every kind of farinaceous substance.-The foreheads of several of the genus, called fulgora, or fire-fly, especially of those that inhabit China, and other hot climates, emit a very lively shining light during the night, which often alarms those who are unacquainted with the cause of the appearance. -To this insect Thomson alludes in his view of the torrid zone:
From Menam's orient stream, that nightly shines
And Mrs. Barbauld:
Some shoot like living stars, athwart the night,
The caterpillars of some of the genus called cicada, or flea-locust, discharge a kind of froth or saliva from the anus and pores of the body, under which they conceal themselves from the rapacity of birds and other enemies.-The papa, or water scorpion, frequents stagnant waters. It lives chiefly on aquatic insects, and is exceedingly voracious.-Many species of the cimex, or bug, feed upon the juices of
plants, and others upon the blood of animals. Some of them are found in waters, and others frequent houses, among which, though it wants wings, is the bed-bug, a pestiferous insect, which is too well known, and too generally diffused. The bugs differ from other insects by their softness; and most of them emit a very fetid smell.-The insect called aphis, or tree-louse, is very common. There are a great many species, denominated from the trees and plants which they infest: they are viviparous in summer, and oviparous in autumn. Numbers of those called vine-fretters are devoured by the ants, on account, it is supposed, of a sweet liquor with which their bodies are perpetually moistened. The caterpillars of the chermes, have six feet, and are generally covered with a hairy or woolly substance. The winged insects leap or spring with great agility, and infest a number of different trees and plants: the females, by means of a tube at the termination of their bodies, insert their eggs under the surface of the leaves, and the worms, when hatched, give rise to those tubercles, or galls, with which the leaves of the ash, the fir, and other trees, are sometimes almost entirely covered.-I shall proceed further in this subject, and finish the remaining orders of the insect tribes in my next paper.
A VIEW OF THE INSECT TRIBES, CONTINUED.
What atom-forms of insect life appear!
LINNE'S third order of insects, termed lepidoptera, has four wings, and consists of three genera only; but the species comprehended under them are exceedingly numerous. All butterflies and moths belong to this order. Their wings are covered with a farinaceous powder, or rather with a kind of scales or feathers, disposed in regular rows, nearly in the same manner as tiles are laid upon the roofs of houses. The elegance, the beauty, the variety of colours exhibited in their wings are produced by the disposition and different tinctures of these minute feathers. The insects of this order, on account of their beauty and easy preservation, have always been the favourites of collectors, and particularly of those of the female sex. When the feathers are rubbed off, the wings appear to be nothing more than a naked, and often a transparent membrane. The feelers of the papilio, or butterfly, are thickest at their extremity, and often terminate in a kind of knob, or head. Their wings, when sitting, or at rest, are erect, their extremities join each other above the body, and the animals fly about, in quest of food and of their mates, during the day.-The moths are divided into two genera, the one called sphinx, or
hawk-moth, and the other phalana, or moth. The feelers of the sphinx are thicker in the middle than at the extremities, and their form in some measure resembles that of a prism. The wings are, in general, deflected, their outer margins declining toward the sides. They fly about early in the morning, and after sunset; and, by means of their proboscis, like the butterflies, they suck the juices of plants.-The feelers of the phalana are setaceous, and taper from the base to the point. When at rest, their wings are commonly deflected; and they fly during the night. Previous to their transformation, the caterpillars of the whole of this genus spin webs for covering and protecting the animals while in the chrysalis state. From a species of this tribe mankind have derived one of the greatest articles of luxury and of commerce which now exists in the world. That seemingly contemptible, and disgusting reptile the silkworm, in its passage from the caterpillar to the chrysalis state, produces those splendid materials which adorn the thrones of princes, and add dignity and lustre to female beauty.
The fourth order of insects is distinguished by the name neuroptera. They have four wings, which are membranaceous, naked, and so interspersed with delicate veins, that they have the appearance of beautiful net-work. Their tail has no sting; but that of the male is frequently furnished with a kind of forceps or pincers. To this order belongs the libellula, or dragon-fly, an insect of very splendid and variegated colours. It is a large and well known fly, and frequents rivers, lakes, pools, and stagnating waters, in which the females deposit their eggs. Under the same order is comprehended the phryganea, or spring-fly: the caterpillars of this genus live in the water, and are covered with a silken tube. They have a very sin