Such is his " short eventful history ; and you now see that the long beak is formed entirely with reference to this economy : it is an auger, fitted to bore holes into shell-fruits, through their envelopes, for the reception of eggs.

There is a very extensive family of Beetles known as Lamellicomes, because the antennal joints are singularly flattened, and applied one over the other, like the leaves of a book (lamella, a leaf). Here is a very common little €hafer found on the droppings in pastures (Aphodius Jimetarius), in which the last three joints, constituting the -club of the antenna, are of an ovate form, and flattened, so as to lie one on another quite close, like three oval M cakes ; and being connected only at one end of the long axis, they open and shut at the pleasure of the animal, like a long pocket memorandum -book of three leaves.

But this structure is seen to still greater advantage in the much larger Cockchafer, so abundant in May in some seasons. For here the joints composing the club are much more numerous (seven in the male, six in the female), and they are proportionally longer and thinner, and therefore more leaf-like. The insect widely expands them, evidently to receive impressions from the atmo-

A>'TE>"NA OF COCKCHAFER.

sphere ; when alarmed, they are closed and withdrawn beneath the shield of the head ; but, on the first essay towards escape, or any kind of forward movement, the leaves are widely opened, and then, after an instant's pause to test the perceptions on the sensorium, away it travels.

In some Beetles each joint of the series has one of its outer angles more developed than the other, and so produced as to make, with the rest of the joints, a saw-like edge ; you may see an example in this Click-beetle or

Skipjack (Elater), but many members of the same family show the same structure in a far higher degree, the angle being drawn out into a long slender rod, which (with its fellows) imparts to the antenna the appearance of a comb.

But much more curious and beautiful are the antennae of many moths, which often resemble feathers, particularly in the group Bombycina, of which the Silkworm is an example : and in the male sex, which displays this structure more than the female. But I will show you a native example.

This is the antenna of a large and handsome, and not at all uncommon, moth, the Oak Egger (Lasiocampa quercvs). It consists of about seventy joints, so nearly alike in size and outline, that the whole forms an almost straight rod, slightly tapering to the tip. Each joint, however, sends forth two long straight branches, so disposed that the pair make a very acute angle, and the whole double series of seventy on each side, form a deep narrow groove. These two series of branches, being perfectly regular and symmetrical, impart to the antennse the aspect of exquisite feathers.

It is. however, when we examine the elements of this structure in detail, using moderately high powers of enlargement, that we are struck with the elaborateness of the workmanship bestowed upon them. Each of the lateral branches is a straight rod, thick at its origin, whence it tapers to a little beyond its middle, and then thickens again to its tip. Here two horny spines project from it obliquely, one much stouter than the other, at such an angle as nearly to touch the tip of the succeeding branch.

Besides this, each branch is surrounded throughout its length with a series of short stiff bristles, very closeset, projecting horizontally (to the plane of the axis of the branch), and bent upwards at the end candelabrum- H 2 fashion. The mode in which they are arranged is in a short spiral, which makes about forty-rive whorls or turns about the axis ; at least in the branches which are situated about the middle of the antenna ; for these diminish in length towards the extremity, bringing the feather to a rather abrupt point.

The entire surface of the branch gleams under reflected light with metallic hues, chiefly yellows and bronzy greens ; which appear to depend on very minute and closely-applied scales that overlap each other. The main stem of the feather,—that is, the primary rod or axis,— is somewhat sparsely clothed with scales of another kind, thin, oblong, flat plates, notched at the end, and very slightly attached by means of a minute stem at the base, —the common clothing-scales of the Lepidoptera, specimens of which we have before examined.

We may acquire some glimpse of a notion why this remarkable development of antennae is bestowed upon the male sex of this moth, by an acquaintance with its habits. It has long been a practice with entomologists, when they have reared a female moth from the chrysalis, to avail themselves of the instincts of the species to capture the

insects: their ears and eyes. male. This sex has an extraordinary power of discovering the female at immense distances, even though she be perfectly concealed; and will crowd towards her from all quarters, entering into houses, beating at windows, and even descending chimneys, to come at the dear object of their solicitude. Collectors call this mode of procuring the male " sembling," that is " assembling" because the insects of this sex assemble at one point. It cannot be practised with all insects, nor even with all moths; with this family, Bombycidce, it is in general successful ; and of these, none is more celebrated for the habit than the Oak Egger. The very individual whose antenna has furnished us with this observation was taken in this way; for having bred a female of this species the evening before last, I put her into a basket in my parlour. One male, the same evening, came dashing into the kitchen ; but yesterday, soon after noon, in the hot sunshine of August, no fewer than four more males came rapidly in succession to the parlour window, which was a little open, and, after beating about the panes a few minutes, found their way in, and made straightway for the basket, totally regardless of their own liberty.

It must be manifest to you that some extraordinary sense is bestowed on these moths, or else some ordinary and well-known sense in extraordinary development. It may be smell ; it may be hearing ; but neither odour nor sound, perceptible by our dull faculties, is given forth by the females : the emanation is far too subtle to produce any vibrations on our sensorium, and yet sufficiently potent, and widely diffused, to call these males from their distant retreats in the hedges and woods. I think it highly probable that the great increase of surface given to the antenna; by the plumose ramification we have been observing, is connected with the faculty; perhaps every bristle of the spiral whorls is a perceptive organ, constructed to vibrate with the tender undulations that circle far and wide from the new-born female, Surely the ways of God in creation are " past finding out."

The male Gnat presents in its antennae a pair of plumes of equal beauty, but of a totally different character. The pattern here is one of exceeding lightness and grace, as you may see in this specimen. Each antenna is essentially a very slender cylindrical stem of many joints (about fourteen); at each joint springs out a whorl of fine hairs of great length and delicacy, which radiate in various directions (not, however, forming a complete circle), curving upward like the outline of a saucer, supposing the stem to be inserted into its centre. The length of these hairs is so great, that the diameter of their sweep equals, if it does not exceed, the whole length of the antenna.

In the tribe of two-winged insects, which we term par excellence Flies (Muscadce), the antenna? are of peculiar structure. The common House-fly shall give us a good example. Here, in front of the head, is a shell-like concavity, divided into two by a central ridge. Just at the summit of this project the two antenna?, originating close together, and diverging as they proceed. Each antenna consists of three joints, of which the first is very minute, the second is a reversed cone, and the third, which is large, thick, and ovate, is bent abruptly downwards immediately in front of the concavity. From the upper part of this third joint projects obliquely a stiff bristle or style, which tapers to a fine point. It is densely hairy throughout ; and is, moreover, beset with longer hairs, on two opposite sides, which decrease regularly in length from the base, making a wide and pointed plume.

Such are a few examples of what are presumed to be the ears of Insects; let us now turn our attention to their eyes. And we can scarcely select a more brilliant, or a larger example, than is presented by this fine Dragon-fly (sEshna), which I just now caught as it was hawking to insects: their ears and eyes. and fro in my garden. How gorgeously beautiful are these two great hemispheres that almost compose the head, each shining with a soft satiny lustre of azure hue, surrounded by olive-green, and marked with undefined black spots, which change their place as you move the insect round !

Each of these hemispheres is a compound eye. I put the insect in the stage-forceps, and bring a low power to bear upon it with reflected light. You see an infinite number of hexagons, of the most accurate symmetry and regularity of arrangement. Into those which are in the centre of the field of view, the eye can penetrate far down, and you perceive that they are tubes ; of those which recede from the centre, you discern more and more of the sides ; while, by delicate adjustment of the focus, you can see that each tube is not open,but is covered with a convex arch of some glossy matter, polished and transparent as crystal. There are, according to the computations of accurate naturalists, not fewer than 24,000 of these convex lenses in the two eyes of such a large species of Dragon-fly as this.

Every one of these 24,000 bodies represents a perfect eye ; every one is furnished with all the apparatus and combinations requisite for distinct vision ; and there is no doubt that the Dragon-fly looks through them all. In order to explain this, I must enter into a little technical explanation of the anatomy of the organs, as they have been demonstrated by careful dissection.

The glassy convex plate or facet in front of each hexagon is a cornea or comeule, as it has been called. Behind each cornea, instead of a crystalline lens, there descends a slender transparent pyramid, whose base is the cornea, and whose apex points towards the interior, where it is received and embraced by a translucent cup, answeriDg to the vitreous humour. This, in its turn, is surrounded by another cup, formed by the expansion of a nervous filament arising from the ganglion, or knot, on the extremity of the optic nerve, a short distance from the brain. Each lens-like pyramid, with its vitreous cup and nervous filament, is completely surrounded and isolated by a coat (the choroid) of dark pigment, except that there is a minute orifice or pupil behind the cornea, where the rays of light enter the pyramid, and one at the apex of the latter, where they reach the fibres of the optic nerve.

Each cornea is a lens with a perfect magnifying power ; as has been proved by separating the entire compound eye by maceration, and then drying it, flattened out by pressure, on a slip of glass. When this preparation wajs. placed under the microscope, on any small object, as the points of a forceps, being interposed between the mirror and the stage, its image was distinctly seen, on a proper adjustment of the focus of the microscope, in every one of the lenses whose line of axis admitted of it. The focus of each cornea has been ascertained by similar experiments to be exactly equal to the length of the pyramid behind it ; so that the image produced by the rays of light proceeding from any external object, and refracted by the convex cornea, will fall accurately upon the sensitive termination of the optic nerve-filament there placed to receive it.

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