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of so many blessings; let us testify on all occasions the gratitude our hearts are filled with, for his hav- ing brought us into existence", and for the gists of reason and the fenses which make that existence delightful.
C HAP. II.
Of The Members Of Insects.
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For. the fake of order I shall divide this Chapter into two sections. In the first, I shall discourse of the external parts of insects; in the second I shall treat of their internal structure. As the former are more easily distinguished than the other I shall be more diffuse upon that subject, and begin with it.
Of the external members of InfeBs.
As all insects have a skin I shall begin what I propose to say of the parts of, insects, by a description of this member.
The skin is the most external integument which nature has given them: it covers their whole body, connects the different parts and retains them in the places to which they are assigned. It is not of the fame quality in every insect. Those whose manner of Iife3 does not expose them to compression, or to violent friction have the skin very delicate and tender. Some have several skLs one above another nearly like the different coats of an. onion. The skin of man and that of the other animals is ruled with an infinity of small pores; i: resembles a sieve or very fine net, the pores answering to the'meshes. By these pores transude a quantity of superfluous humours which are thrown off" by sensible or insensible perspiration. The skin of insects h.is likewise pores for the fame use, and so smaii, that the) are with difficulty seen. As some animals change their hair and even their st;in every year, experience shews us that insects do the lame. Some thiow it off but once ayear, others four times.
Insects which creep into holes, or fissures, where they are exposed to pretty violent rubbing, have their Ikin harder than others: and even some have it fortified with scales. It likewise serves to defend insects from the Injuries of the weather ; it is ot the fame use to them that scales are to serpents and fishes, shells to crabs or shell fish, feathers to birds, and hair to the most of quadrupeds. As insects in general are but small, the heat of the Sun would soon dry up the internal humidity of their bodies, and exhaust their animal spirits, were not they enveloped in a hard skin, which prevents that inconvenience. It is the instrument of morion to those that want ieet ; by extending and contracting it alternately, they transport themselves from place to place.
Lastly, the skin of insects may be considered as a *oat of mail with which God has armed them as a protection from external danger. "Thou hast cioath"ed me with skin," jays Job, Chap. X. ii. to express the means which God had employed to unite, connect, and preserve the different parts he was composed of. The Deity has been equally attentive to
T insects insects, and it is for the fame purpose that he ha* likewise cloathed them with a skin.
It is so difficult to distinguish the head of some insects that one -would be almost tempted to believe they had none. Some have it exceeding small in proportion to their body, others very large. It is not in all of the fame shape; it is round, flat, oval, broad, acuminated or square in different insects. In some it is smooth, in others rough, and some have it set with hairs to suit their manner of life. There is also great d;versity in the situation of the head. In some it is quite distinct, but in others it is not easy to di;cov;r it. Some conceal it under their back, like Tortoises under their shell, so that it cannot be seen. Though most have it straight forward, some have it bent down, and some have a triangular mark on their forehead.
Winged insects which have feet are furnished with antennae on their head, above the eyes, though some have them seated on the rostrum, as all the Curculios. In the antennae there are many articulations that insects may bend them with facility, and the number of the articulations varies with the necessities of the various insects. It is rare to find caterpillars with antennae, but there is a brown caterpillar which lives in society that is distinguished by antennas with three articulations. Those of the musk, beetle have four, those of the pediculi of the Peacock, five; those of the aphides of the cabbage, six; those of the Ichneumons that are bred in the body ot the caterpillar with 72 folds, seven; those of some beetles eight. Ihere are insects which have still a greater number of articulations,in their antennæ. Such are all the species of Cerambyx which have tenj the earwig eleven ; the Tipula phdænoides has fourtwu j and the. ichneumon, that breeds in the body of the
green caterpillars which curl up the leaves has sixteen ; the antennas of a Phalæna which feeds on the alder has forty articulations, those of the Phalæna Euonymella fifty; and those of another bred on the willow sixty. Lastly in those of some grasshoppers, there are from eighty to an hundred articulations.
These articulations are not of equal size, and some are longer than others; some are formed of little spherical bodies like a string of beads, more or less distant; these beads are bare in some, but garnished with hairs in others ; in general they are so small that they cannot be seen distinctly but with a glass; In some insects they are hemispherical, in others heartfliaped, and lastly some are toothed like a saw.
The extremity of the antennæ in some insects is thickest, forming a knob, the whole somewhat of the figure of a drum-stick. That knob is sometimes cleft and divided into several branches. The mast of the antennæ is sometimes smooth, and sometimes fringed. These last are of two sorts, the one having fringes only on the outside, the other on both sides, like the feather of a bird. This is their appearance when seen with the naked eye, but if a magnifier is employed, we find that each particular filament of the fringe is itself a feather, having a quill and a plume like those of a bird.
The antennæ are seated on small tubercles by . which the insect can bend them in all directions. They are not always carried in the fame way, some infects bearing them straight forwards, others bent, others turned aside, according to their manner of life.
Antennæ have been given to insects with different views and for different purposes. It appears to have
T a been been the principal inten'ion of the Creator that they should serve vittzd of hand?, as they feel objects with them in order to jud-je whether they are useful or pernicious. When dust has fallen upon the eyes of some injects it is with thur antemæ that they clean them. It is the; more necessary that they should be provided with 'h'.- means of removing this dufl as thev have no eye brows, and are therefore more exposed to the inconvenience. In this cale the antenna; are of the "ame use with our fingers. They likewise serve insects as the organ ot smell, and by them they discern odours both near and at a distance. The males employ them in caressing the females. They are a fort of measuring rod to others, with ■which they found the depth of the holes they mean to retire to. Lastly, as we have observed above, the antennas are one of the marks by which the males of many species may be distinguished from the females.
The structure of the eye in man and other animals demonstrates, jn the most incontestible manner, the power and wisdom of him who made it; but, the evidence of these perfections, drawn from the structure of the eye in insects, is not less strong. It is true that some insects are destitute of the organ of sight, but by far the greater number are possest of it. The form of their eyes is very various; some have the lustre, and almost the roundness of pearls, some are hemispherical, others spheroidal. They are not all of the same colour. We see many butterflies wish eyes as white as snow, those of spiders are qnite black, th:)se of some aphides are of the colour of amber, of jasper cr vermilion; the brilliancy in the eyes of some of the muscæ is like that of gold, for which reason they go by the name of the golden-eyed flies; those or the green grasshoppers have the colour of au emerald j Lilly, the eyes of some have