With all deference to so respectable an authority, I cannot help seeing that such is not the structure of the antlia before us. It is evident to me that each half tube is composed of a membrane stretched upon stiff horny semi-rings., doubtless composed of chitine, and certainly not muscular. By bringing the outline of the rounded exterior into focus, we see that these rings form sharp ridges ; and by tracing them onwards to the attenuated extremity of the organ, we see them gradually give way to transverse lines of interrupted ridgy warts upon the outside of the membrane. The true muscles appear to be indicated by those oblique lines and bands that are seen in the interior, beneath the horny rings.

This specimen shows very distinctly that the two sides are but semi-tubular ; and, as one pair of the opposing edges are open at each extremity, and the other pair separate throughout, we are able to discern very clearly the array of hooks, by which the edges are united at the will of the animal. No trace of the curious little I ointed barrel-shaped papillce is found here, but I have set n them in other examples.

It seems highly probable, from the observations of the excellent anatomist just named, that the exhaustion of the nectar of a flower, which is effected with great rapidity and completeness, is a process dependent on respiration, and connected with the air-pipe that permeates each division of the sucker.* It will not be a very violent transition if from the suckingpump of the Butterfly I carry you to the silk-spinner of the Caterpillar. Here I have a Silkworm in the act of beginning: its cocoon; by inclosing which in this glass tube we shall conveniently have the insect at command, and shall be able to view the process under a low magnifying power and reflected light. Now the grey THE StTCKEE OF A BUTTERFLY. faSe of the worm is presented to A small portion of one halfcylinder. us ; and we can see, below the edge of the head-shield, a short broad upper lip, forming two blunt points. Below this is the pair of strong brown mandibles, convex outwardly and concave inwardly, each cut at its broad biting edge into several teeth. Below these are two little points which represent the maxillce, and between them a blunt rounded knob, which is the lower lip (labium).

You may also see on each cheek, close to the base of the mandible, a little pit, out of which rises a short columnar organ tipped with two bristles ; these columns are the incipient antennae, Outside them you may discern, on each cheek, a series of six globes of glass (so they appear) set in the substance of the skin,—five forming a semicircle, and one in the centre ; these ; re

Mr. Darwin, in his admirable work On the Fertilisation of Orchids, p. 33 et seq., has shown that the tubular proboscis of Lepidoptera, while used by the insect solely for the collection of nectar, is indirectly and unintentionally used for the transferring of pollen-grains from flower to flower ; and thus becomes a most important agent in the propagation of plants. (See his remarkable figure on p. 37 op. cit.)

" the windows at which the [silkworm's] soul looks through "—provided he has any soul ; in prosaic parlance, his eyes.

Now, having thus introduced the several members of our useful friend's physiognomy to you, let me call your attention to a fleshy wart just beneath the lower lip, and midway between the bases of the two fore legs. This wart terminates in a horny point not unlike a bird's beak, which is perforated, and from the tip of which the glistening yellow filament of silk is ever drawn out, as the caterpillar throws his head from side to side. This pointed wart is the spinning organ ; and the thread of silk is, as it issues from the orifice, a fluid gum, which hardens immediately on its exposure to the air. The silk gum is secreted by the caterpillar in two long blind tubes, which lie twisted and coiled in the interior of the body, occupying nearly the whole space, except that which is taken up by the great digestive canal. These become very slender as they approach the head, and at length terminate in a reservoir, which opens by the little pointed wart which you have just seen.

Many caterpillars are able to suspend themselves at pleasure by means of the thread which they are spinning, lengthening it and "stopping it off," at will. This latter operation they perform (though they cannot recal the thread when once it has issued) by means of an angular point formed by the two slender tubes at their junction in the reservoir; thus compressing the thread of gum, and so preventing any more from issuing. The gum is perfectly colourless in the reservoir; but, as it issues forth, it becomes coated with a varnish, which is secreted in the same organ, and which is poured out at the same time. In the case of the common Silkworm, this varnish imparts to the silk that brilliant yellow hue which it generally possesses, and which, as the varnish is soluble, can be easily discharged from it in the manufacture.

Chapter X. Insects: their Ears and Eyes

A very wide field of observation, and one easily cultivated, is presented by the organs of sense in the Insect races, and in particular by those curious jointed threads which proceed from the front or sides of the head, and which are technically called antennce. These may sometimes be confounded with the palpi, examples of which organs we have been lately looking at ; for in a carnivorous Beetle, for instance, both palpi and antennce are formed of a number of oblong, polished hard joints, set end to end, like beads on a necklace. And it is probable there may be as much that is alike in the function as in the form of these two sets of appendages ; that both are the seats of some very delicate perceptive faculty allied to touch, but of which we cannot, from ignorance, speak very definitely. It is likely, indeed, that sensations of a very variable character are felt by them, according to their form, the degree of their development, and the habits of the species.

It is not impossible, judging from the very great diversity which we find in the form and structure of these and similar organs, in this immense class of beings, compared with the uniformity that prevails in the organs of sense bestowed on ourselves and other vertebrate animals,— that a far wider sphere of perception is open to them than to us. Perhaps conditions that are perceptible to us, only by the aid of the most delicate instruments of modern science, may be perceptible to their acute faculinsects: their ears and eyes. ties, and may govern their instincts and actions. Among such we may mention, conjecturally, the comparative moisture or dryness of the atmosphere, delicate changes in its temperature, in its density, the presence of gaseous exhalations, the proximity of solid bodies indicated by subtle vibrations of the air, the height above the earth at which flight is performed, measured barometrically, the various electrical conditions of the atmosphere ; and perhaps many other physical qualities which cannot be classed under sight, sound, smell, taste, or touch, and which may be altogether imperceptible, and therefore altogether inconceivable, by us. It is probable, however, that the antennae, are the organs in which the sense of hearing is specially seated; a conclusion which has long been conjecturally held, and which is confirmed by some observations recently made on the analogous organs in the Crustacea^ which I will allude to more particularly presently.

The forms which are assumed by the antennae of Insects are very various; and I can bring before you only a very small selection out of the mass. One of the most simple forms is that found in many Beetles, as in this Carabas, for example. Here, each antenna is composed of eleven joints, almost exactly alike and symmetrical, each joint a horny body of apparently a long-oval shape, polished on the surface, but not smooth, because covered with minute depressed lines, and clothed with shaggy hair. There is, however, a slight illusion in the appearance : it seems as if the dividing point of the joints were, as I have just said, at the termination of the oval, but when we look closely we see that the summit of each oval is, as it were, cut off by a line, and by comparing the basal joints with the others, we see that this line is the real division, that the summit of the oval really forms the bottom of the succeeding joint, and that the constricted part is no articulation at all. The first, or basal joint (called the scajms), and the second (called the pedicella), differ in form from the rest here but slightly, but often considerably. The whole of the remaining joints are together termed the clavola.

You may see a considerable variety of figure and of aspect generally in this tiny Weevil, which may be accepted as a representative of a great family of Beetles, the Curcidionidce. The manner of their insertion strikes us at first sight as peculiar, as is in fact the aspect of the whole head. Instead of a thick substantial solid front, with powerful widely-gaping jaws, such as we saw in the Carabs, a long rod-like proboscis here projects from between the eyes, as long as the whole animal, curving downwards, and carrying at its very extremity a minute mouth, with all the proper apparatus of lips, jaws, and palpi. Moreover, the antennce are planted on the two sides of this beak, about its mid-length; and they are curiously elbowed, each projecting horizontally at a right angle to the beak for a considerable distance, and then with a sharp angle becoming parallel to it for the remainder of their length. So that, supposing the terminal half of the beak to be broken off just behind the insertion of the antennce, the whole would compose the letter T. Now, the first bend of this angle is composed of a single joint, the scapus, which is, in this family, greatly lengthened ; and then the two or three final joints are much thicker than all the others, and are as it were fused together into a large oval knob, called the club.

Now, a word or two in explanation of this very singular form of head and head-organs. The larva or grub stage of these insects is destined to be passed in the interior of fruits and seeds; the individual which we have been examining (Balaninus nucum) was born one morning in August, in the interior of a hazel-nut. Its parent had chosen a suitable nut, just then when it was set for fruit and as yet green and soft ; and had with her proboscis, insects: their ears and eyes. or rather with her jaws at its tip, as with a gimlet, bored a tiny hole through the yielding shell into the very interior ; then, turning round, and inserting the extremity of her abdomen, with its ovipositor, she had shot an egg into this dark cavity. The juices poured forth at the wound soon healed the orifice ; the nut grew ; and presently the egg became a little Avhite grub. He then rioted in plenty ; prolonged his darkling feast " From night to morn, from morn to dewy eve.;" —'twas all " dewy eve " to him, by the way, for no ray of light saw he, till that prosperous condition of existence was done. Xo wonder he grew fat ; and fat those rogues of nut-weevils always are, as you well know. Well, when the nut fell, in October, the kernel was all gone, completely devoured, and our little highway-robber was ready for his winter sleep ; he gnawed a fresh hole through the now hard shell, made his way out, and immediately burrowed into the earth, where he lay till June ; then became a pupa, and emerged just what you see him, a long-snouted beetle like his mother, in the beginning of August. "

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