out what it seems to us to be, rather than what it is. Even with this limitation, the inquiry will prove sufficiently difficult. The properties of instinct are a little more inscrutable than those of the human mind, inasmuch as we have our own consciousness to assist us in this case, while we are left to infer the peculiarities of instinct from its outward manifestations only. And moreover, the inquiry involves an understanding of the workings of the human mind; for it is only when viewed in contrast with the rational endowments of man that the character of instinct is best known. All other questions connected with the subject are subordinate to this one of the apparent difference between instinct and reason. Many definitions have been given of instinctive actions. These differ widely in their extent, and are for the most part quite inadequate. Some writers have ranged under this term all those customary habits and actions which are common to all the individuals of a species. According to this definition, almost every action of animated life is instinctive. But the general idea of an instinctive action is much more restricted; it is one that is performed without instruction and prior to experience,--and not for the immediate gratification of the agent, but only as the means for the attainment of some ulterior end. To apply the term instinct to the regular and involuntary movements of the bodily organs, such as the beating of the heart and the action of the organs of respiration, is manifestly an extension of the ordinary acceptation of the term. Organic actions of a similar character are also performed by plants, and are purely mechanical. "In the lowest and simplest class of excited movements," says Müller, "the nervous system would not appear to be concerned. They result from stimuli directly applied to the muscles, which immediately excite their contractility; and they are evidently of the same character with the motions of plants." Thus, the heart is excited to pulsation by the direct contact of the blood with the muscle. The hand of a sleeping child closes upon any object which gently touches the palm. And it is in this way, doubtless, that the Sea Anemone entraps its prey, or anything else that may come in contact with its tentacles. But so far are these movements from indicating of themselves the action of any instinctive principle, that they are no proof of animality; for a precisely analogous power is possessed by the sensitive plant known as the Fly-Trap of Venus (_Dionoea muscipula_): "any insect touching the sensitive hairs on the surface of its leaf instantly causes the leaf to shut up and enclose the insect, as in a trap; nor is this all; a mucilaginous secretion acts like a gastric juice on the captive, digests it, and renders it assimilable by the plant, which thus feeds on the victim, as the Actinea feeds on the Annelid or Crustacean it may entrap." In the animal organization a large class of reflex actions are excited, not by