In speaking of the _antennæ_ and _palpi_, I have called them sensiferous organs. The organ necessarily implies the perception, or whatever it may be, conveyed to the sensorium through its means, this being the receptacle of the sensation or idea, the external organ communicates. It is thus that activity is given to a power of discrimination, and consequently of election or rejection by the creature. This sensorium, in the higher animals, is the brain; and in the lower, where the nervous system is very differently constituted, a ganglion, or knot of nervous substance. That this brain, or ganglion, is the power exercising the control, may not be admitted, although it is there that our research compulsively terminates. The power itself is essentially spiritual, acting through a material agent, and may be an efflux of this nervous mass. Whether it cease with the death of the organ, we have no means of knowing. That it may be in some way analogous in nature to the human mind, but to a limited extent, there is reason to surmise. This power, in its collective capacity, is called INSTINCT. This instinct is a faculty whose clear comprehension and lucid definition seem impossible to our understanding. Its attributes are very various, and its operations are always all but perfect. It is an almost unerring guide to the creature exercising it, and is as fully developed on its awakening as is, and with it, the imago upon its transformation. Although observation has thought to have detected that experience sometimes uses a selection of means, and thus occasionally modifies the rigid exercise of the faculty, by adapting itself to the force of circumstances, it, when so, evidently assumes a higher character than has been willingly accorded to it. This instinct teaches the just disclosed bee, without other teaching than that of the intuitive faculty, where to find its food, and how to build its abode. It directs it to the satisfying its material needs, and instructs it to provide for its offspring, and to protect them whilst in their nidus; the impulse to which follows immediately upon the satisfaction of the sexual desire, to which it is the seal. If it be _memory_ that guides the bee from its wide wanderings back to its home, this then becomes an attribute to the faculty. Instinct indicates to them their enemies, and the wrongs these may intend, and shows them how they may be repulsed or evaded. In some of its operations it seems to be of a more perfect capacity than the operative faculty of human intelligence. The senses evidently possessed by our insects are sight, feeling, taste, and smell, but whether they hear we cannot know, although the antennæ have been supposed to be its organ, for the apparent responsiveness of these to loud and sudden sounds, may equally result from the agitations of the air these produce. Their possession of touch, taste, and smell, are implied from what has been observed.