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THE

A MERICAN

JOURNAL OF SCIENCE AND ARTS.

[SECOND SERIE S.]

ART. I.-Some Principles of Animal Psychology; by D. F.

WEINLAND. Read before the American Association, at the Baltimore Meeting. May, 1858.

THE true difference between plants and animals consists in this, that animals have a consciousness of an outer world, while plants have none.

We are accustomed to distinguish animals from plants by their being endowed with free, that is, voluntary locomotion, and with feeling. Linnæus long since said: Saxa crescunt, Vegetabilia crescunt et vivunt, Animalia crescunt vivunt et sentiunt. A certain kind of feeling however cannot be denied tu some plants, for instance to the Mimosa. As to the “voluntary" motion, which modern handbooks generally consider as the standard difference between plants ind animals, I shall try to show that the term voluntary is far better replaced by the term “conscious of an outer world.” What is it that strikes the microscopist as vegetable-nature in the Navicula, and as animalnature in the Monas? Both move, but the Navicula in its steady onward course runs foul of every obstacle that crosses its way, while the Monas dodging with ease and dexterity, tinds its winding way through a host of obstacles, apparently without touching one. It is this evident consciousness of surrounding objects that characterizes the animal.

The consciousness of an outer world is the fundamental principle of the soul of animals. The consciousness of self, of the Ego, SECOND SERIES, Vol. XXVII, No. 79.-JAN , 1859.

which is rather obscure, even in the highest animals, as it is also in the human child, is proportionate to the consciousness of an outer world; it is a result of the latter, for it is only in opposition to an outer world, that the animal conceives itself and becomes conscious of itself. The degree of psychical development in different kinds of animals may be judged from the degree of development of the consciousness of an outer world. The soul of an animal is the higher, the more relations it has to the outer world, that is, the larger the horizon of its outer world. The latter point I will explain with some illustrations taken from the lower animals, in which the psychical life is more simple, and therefore easier to understand.

What is the outer world of a coral-polyp ? With hundreds of its kind it lives on the same coral-stock; it is there fixed and is able to move its mouth and tentacles only; thus it awaits its prey, a little craw-fish, without eyes, and without touching it—by a sense unknown to us-it perceives the presence of its prey, throws out its lasso-cells and catches it. Every individual has both the sexes united. Though closely crowded together, I never could notice a trace of psychical relation between the polyps of the same stock. What is the outer world of such a polyp? The whole range of its psychical life is evidently confined to the objects of food.

Let us now rise one step bigher, to a Helminth, an Ascaris, that inhabits the intestine of some vertebrate. In regard to feeding it stands evidently on the same, perhaps on a lower level than the polyp, but still we must rank it psychically higher! The sexes are divided, and in the line of reproduction the male and the female individuals meet each other. There is therefore besides a consciousness of an outer world in regard to food, evidently also, a consciousness of other living individuals, although that consciousness may be dark enough.

We may take a bee, a wasp, or any of the social Hymenoptera, as a third step. In the bee the consciousness of the existence and the interest in other living individuals is not confined merely to the season and to the instinct of reproduction, but to the whole life. At any time the individuals of the bee-hive know each other, give each other signs, help each other, fight for each other. It is evident how much more varied the relations to the outer world, how much more extensive the latter is for a bee than for an Ascaris, and still more than for a polyp.

In order to judge how extensive the outer world is, of which an animal is conscious, that is, in order to judge about its psychical hor. izon, we must investigate the organs of that consciousness, that is, the psychical organs of animals.

The psychical organs of animals are of three kinds : (1.) RECEPTIVE organs, organs which receive impressions from the outer

world; here belongs the whole skin-system including the senses. (2.) REFLECTIVE organs, that is, organs which combine the impressions received by the receptive organs, here belongs the central nervous system. (3.) REACTIVE organs, that is, oryans which react upon the outer world ; they are the servants of the central nervous system, which go from within outward, while the receptive organs go from without inward. These reactive organs consist in the whole system of voluntary muscles, with the bones which belong to them.

The stuilent of animal psychology has mainly to depend upon the third kind of organs, namely, the reartive, not only because the functions of the receptive and reflective organs are more or less hidden, . but also because their functions are in fact the mirror of the whole psychical life of the animal, being also the resultunts of the functions of the receptive and reflective organs.

The functions of the reactive organs are the voluntary motions. When observing these motions in an animal more closely, we soon perceive two kinds of motions, which are in their ends entirely different.

Let us look at a dog. We see in the first place, that it makes many motions, which have no other purpose than to satisfy the Ego of the doy itself. Such are the motions by which it eats, drinks, etc. These motions we call subjective, as having reference exclusively to the Egn, to the subject of the dog itself. But besides these, we see other motions in the dog, which have no immediate reference to the Ego of the dog, but to other dogs, or to men; we see motions of the head, the eyelids, the tail, of the whole body, by which the dog would show to other dogs or to his master, what it thinks, feels or wants. This second kind of motions I propose to call sympathetic motions.

The subjective motions are common to all animals and must be so. We have seen them in the polyp, and we see them in man. They are, generally speaking, the same throughout the animal kingdom. But the greatest diversity exists in regard to the sympathetic motions with different animals, and it will be evident from the following illustration, that the degree of their development is the principal standard for the student of animal psychology. The more the organs for sympathetic motions are developed, the more extensive is the outer world of which the animal is conscious, and the larger is its psychical horizon. Let us compare a fish, a lizard, a monkey and finally man in regard to the organs for sympathetic motions. The fish lying horizontally in the water, its head, neck, trunk and tail forming one continuous massy body; its eyes cold and stiff, turned sidewards, nearly immovable; no voice; hardly traces of an ear:-what organs has this animal to show to its fellow-creatures the processes of its soul? How different a spectacle offers a lizard to the thinking observer! Its body raised upon four legs; a dis

tinct neck, upon which the head plays freely, thus giving at once to the eyes a horizon not only towards the sides but also upwards and downwards. And how expressive are those eyes! their expression mainly lies in the play of the eyelids, (of which the fish is destitute,) so that from the eyelids alone an experienced observer will perceive, whether the lizard is contented, or sad, or enraged. The tongue, which in the fish is a nere organ for swallowing food, is in the lizard a true organ of sympathetic motions, for we often can see them licking at each other in play or in love. The ear is well developed; they like music and some of them have a voice, as those well know who have spent a night in a virgin forest of the tropics. I will not dwell upon the intermediate degrees of psychical organization as exhibited in birds and the lower mammalia, but consider next the monkey. How rich at once the organization for sympathetic motions. The front ligs—in the lizard mere locomotory organs are in the monkey arms with which the mother embraces the young. The foot, a mere organ of support in the lizard, has become a hand, with which he grasps the hand of his mate. The lips, of which there is no trace in the lizard, are in the monkey very perfect ory:ins of sympathetic motions. With the lips and the whole play of the muscles of the face, with the eyelids, with the tongue, with sounds, etc., the monkey shows to his fellow creatures what it likes and what it hates, what it wants and what it thinks.

Finally let us consider man. The natural position of the monkey is on four legs; in consequence, his head is naturally half bent downwards, thus confining the horizon of his eyes, and his front legs though used as arms are at the same time stilí organs of locomotion, mainly of climbing. On the contrary, man standing upright on his legs has his arms and hands free, they are perfect organs of sympathetic motions, locomotion being confined to the lower extremities. His head stands free upon the neck, thus giving to all the senses and particularly to the eyes the largest possible horizon. His eye is the mirror of his soul in which the fellow-man reads the innermost thoughts and feelings. Ilis lips, tongue, and the whole apparatus of the larynx produce by their motion the most perfect of all sympathetic motions, language. These aud many more not less interesting points are suggested by a comparison of the organs for sympathetic motions, and from the facts principles of practical iinportance for educational purposes may be derived; but what I have mentioned is sufficient illustration of the truth that owing to the great perfection of organs for sympathetic motions, the relations of man to his fellow beings are far the most diversified and at the same time the niost intimate, not only to his fellow beings but to the outer world generally. Whatever our civilization has performed, has been done by improving these natural pyschical organs. The outer world of the polyp is confined to the objects of its prey, the outer world of the civilized man is the Universe. Our steam vehicles on land and on sea, what else are they than improved organs of locomotion; our letters, our books, our journals, our telegraphs, what else are they than organs of human language on a more extended scale? our telescopes, our microscopes, what else are they than the receptive sense of the eye extended. Thus all the inventions of our civilization tend to enlarge the horizon of the individual man. And this is the true destiny of man. I do not know of a greater motto or lifeprinciple than that which was written on the temple of the oracle of Delphi in ancient Greece: I'vôli osavior~"Know thyself;" but another is equally great, written by Wilhelm von Humboldt, the great philologist, (brother of the author of the Cosmos), it is this: “I wish to leave wben dying as little as possible behind me in this world, with what I have not come in cuntact," that is wbat I have not mastered with my mind. Humboldt wanted the most perfect knowledge of the outer world, while the Greek philosopher wanted the deepest knowledge of himself. One of these sentiments is only the reverse of the other, or rather it follows immediately from the other. The most thorough knowledge of the outside world involves the deepest insight into ourselves; just as in morals, he who loves his neighbor the truest is the happiest, and thus loves himself the truest.

ART. II.—On some unusual modes of Gestation ; by JEFFRIES

WYMAN, M.D. Communicated to the Boston Soc. of Natural History. (See Proceedings of the

Suciety, Sept. 15, 1857.) AMONG Batrachians the circumstances under which the young are developed, though less varied than in some of the other classes of vertebrates, still present a considerable range. By most species the eggs are deposited in the water either upon aquatic plants or on the bottoms; by others, as in Salamandra erythronota, they are laid in damp places under logs or stones; with some the evolution of the embryo commences a short time previous to the laying of the egg and is completed subsequently, while there are other species which are wholly viviparous.

The most remarkable deviations from the ordinary modes are to be found in those instances in which the eggs, after being laid, are again brought into a more or less intimate relation with the parent, as in the “Swamp toads” (Pipa Americana) of Guiana, where each ovum is developed in a sac by itself on the back of the female, in Notodelphys of Venezuela, where all the eggs are lodged in one large sac, also on the back, and is analogous to the

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