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and Dysmorphosa were the same, and that all the life-histories which have been described are modifications of that which was exhibited by this ancestor.

The series which has been given shows that this ancestor must have developed directly from the egg, its adult stage must have been the most important part of its life, and the hydra stage only a transitory larval condition. As, in certain lines of descent from

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this ancestor, the conditions of life became more and more favorable for the larvæ, and as successive generations of larvæ became more and more adapted to these conditions, the larval life gradually increased in length and importance, and threw the adult sexual stage more and more into the background, until, in the case of Dysmorphosa, we have a colony of long-lived larvæ, which embody all that is most distinctive and characteristic of the species,

and the adult jelly-fish lives only long enough to effect the wide distribution of the eggs, and the establishment of new colonies of larvæ.

Something very similar to this has occurred in a few insects. The caterpillar stage of most butterflies is simply a preparatory step directed toward an end, the production of the perfect insect; but the bagworm is a butterfly in which the larval life is most important, for, while the caterpillar lives long, the female insect never escapes from her cocoon, but after her final transformation lays her eggs within it and dies, while the male lives only long enough to find and fertilize the female, and then dies also.

In the case of the hydroids, the power of budding, a power which is almost absent in insects, enables the larval life to assume a degree of importance which it could not have if the larva remained simple, for it has rendered division of labor possible, and has produced polymorphic communities, most of the members of which are out of the line of succession. The gradual reduction of the adult life is also facilitated by the process of budding, as this effects a great increase in the number of adults which come from each egg, and thus secures the sexual reproduction of the species, notwithstanding the shortening of the life of each adult.

The shells of hermit-crabs often carry colonies of another hydroid, which is so similar to Dysmorphosa that a drawing of one will answer for the other. They are almost exactly alike, and it is only after careful examination that any difference between them is discovered; but, inconspicuous as the difference is, it is highly important, for in the second form, Hydractinia, the adult locomotor jelly-fish stage has been completely lost, and the whole life of the species has become centered in the larvæ. The blastostyles produce buds, which acquire some rudimentary traces of the organization of jelly-fish, but they never become free or complete their development. While still on the blastostyles, they produce eggs or spermatozoa, and having thus accomplished their purpose and secured the perpetuation of their race, they die. The life of Hydractinia is shown in Diagram VII:

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This is by no means the end of the story, for the many species of hydroids without any jelly-fish stage present all stages in the gradual simplification of the sessile medusa buds, until at last all traces of the structure of the jelly-fish disappear, and they are

degraded into simple accumulations of reproductive cells-reproductive organs-on the bodies of the hydroids.

No group of animals presents a more complete record of the process of evolution of species than the hydro-medusæ, and the comparative study of the different species gives, with a wealth of detail which is entirely beyond the scope of a short article, all the steps in the progress of modification. The minute gradations are so numerous that a long training is required to grasp them all without confusion, and to read the history which they exhibit, but those which I have selected are sufficient to illustrate the manner in which the larval life has gradually grown into prominence, and has become evolved and specialized, while the adult life has dropped more and more into the background, and has finally disappeared completely.

MAN IN RELATION TO THE LOWER ANIMALS.

ON

BY PROF. EDWIN EMERSON.

N the published bills and circulars of the "Fidelity Trust Company," of Philadelphia, is a representation of a strongbox guarded by a watchful dog. The faithful protection of the dog is a striking emblem of the mission of the Fidelity Trust Company. Fidelity to a trust is certainly a moral quality of a high order. This is such a well-known characteristic of the family of dogs as to have become proverbial. It is a matter of common observation that members of the better class of dogs, such as Newfoundlands and Saint-Bernards, show also other moral qualities: they have a high sense of honor, can not be bribed, will not steal, etc., and are true to the death as to matters committed to their trust. To deny to such animals the possession of moral qualities seems to be absurd. But moral qualities and reasoning faculties are not confined, in the animal world, to dogs alone; far from it. Many tribes of animals have the habit, when necessity seems to require, of posting sentinels to guard from surprise. This practice is in use by the chamois, the deer, the wolf, the goat, the wild horse, the elephant, the beaver, the monkey; the raven, the crow, and many other birds. To consider in advance as to the necessity of placing sentinels, and then to resort to that form of strategic device, is a decided proof of the possession of no small perceptive and reasoning power; and the fact that the sentinels faithfully fulfill the onerous duties of their trust is a striking proof of advanced moral qualities.

Any theory in regard to man's place in nature which denies. some degree of reason and moral perception to the lower animals

is so wide of the facts that it must be a mistaken theory. It places man too high, and assigns to the various tribes of lower animals too low a position in the moral and intellectual scale to agree with observation. A wide and unnecessary chasm is thus placed between man and the inferior animals, when, in fact, the lower tribes of men and the higher tribes of animals, such as elephants, foxes, dogs, and monkeys, are not so greatly apart in the line of intelligence and moral perception. Savages recognize this affinity. Thus we are assured that certain tribes of negroes regard monkeys as their near relatives, who have been deprived of the power of speech on account of their mischievousness and badness.

The wonderful manifestations of instinct are so remarkable that the old theory ascribed it to God himself having directly implanted it," from without and from above"; but that theory has been set aside by modern investigation, and it is now very generally recognized that instinct is the hereditary result of long experience. This being the case, all the manifold exhibitions of reflection and reason, and careful, self-denying affection shown. by the various tribes of animals, must be ascribed to the workings of their intellectual and moral faculties through long periods of time.

Dr. Mark Hopkins, in his "Scriptural Idea of Man," teaches that man alone, among the animals upon the earth, is dignified by the possession of what constitutes him "a person." Personality, according to Dr. Hopkins, arises from consciousness, reason, and a moral nature. Consciousness is defined (p. 48) as "the knowledge of his own existence by a being who knows himself to be. . . . Thus arises a knowledge of rights and obligations. . . . Thus man is formed to rule over the lower creation. . . . From all that is below him man is most widely separated" (p. 106). "Of dominion over itself, over nature, or over its fellows, no brute can know anything; nor can it know anything of an intelligent mediation between nature and God. Being destitute of rational and moral elements, the brute can not have the first dawning of either of these ideas" (p. 103).

In reply to these statements we observe-that brutes do rule over themselves, oftentimes exhibiting remarkable self-control. Nothing is more common than for the parent animal to abstain from food until the young ones are provided for. Brutes do rule over each other-scarcely any of the gregarious animals fail to show this power; it is true of monkeys, stags, elephants, bulls, and birds in their migrations. The shepherd's dog rules over the flock committed to his care almost as well as his master As for dominion over nature, the brutes exercise just as much of it as is necessary for their well-being and preservation. A bird that builds its nest in a sheltered place exercises control over nature,

in its degree, quite analogous to the work of a human architect. "The foxes have holes, and the birds of the air have nests." How does the fox get its hole, or the bird its nest? They make them for their purposes, and this is certainly control over nature to that extent. How does the fox support his family if he has no control over nature? Do hens and chickens run into his hole and ask to be eaten? Dr. Hopkins does not seem ever to have heard of the way in which a tribe of monkeys prepare to rob a corn-field. Let us describe it. When they get ready to start on their expedition, an old monkey, the leader of the tribe, with a staff in his hand, so as to stand upright more easily, marches ahead on two legs, thus being more elevated than the others, so as to see signs of danger more readily. The rest follow him on all-fours. The leader advances slowly and cautiously, carefully reconnoitring in all directions, till the party arrives at the cornfield. He then assigns the sentinels to their respective posts. All being now in readiness, the rest of the tribe ravage and eat to their hearts' content. When they retire, each one carries two or three ears of corn along, and from this provision the sentinels are regaled on arrival at their lair. Here we see ability to rule and a willingness to submit to rule; a thoughtful preparation of means to the end in view; and a recognition of the rights of the sentinels to be suitably rewarded at the close of the expedition. Wherein does all this differ from a similar foray of a tribe of savage men? The only difference is in degree; otherwise, it is much the same. Dr. Hopkins's proposition that animals are not possessed of consciousness is mere assertion. He offers no proof whatever. A dog appears to be perfectly conscious of his existence. All his actions are in entire accordance with that view of his activity. Give him a bone, and he seems to be conscious of his rights, too, and is ready to defend them. Observe a dog of one or two years of age, and a child of four or five years, playing together; they understand each other perfectly well, and seem to get equal pleasure out of the sport. Their consciousness of existence is about the same. When the dog gets older, and accompanies his master to hunt, he understands his duties, and performs them about as well as the man performs his share. The dog hunts as truly as the man; takes a lively interest in all the proceedings; is joyous over success, and cast down in case of failure. To deny consciousness to such a being is absurd. It is quite true that the dog has not studied the Cartesian system of philosophy, and can not say to himself, cogito, ergo sum; but, neither can the boy who plays with him, nor, probably, the man who hunts with him. A power of analysis and metaphysical introspection is not possessed by young persons; nor, generally, by uncultivated men. They live in the present. They are satisfied with a consciousness of

VOL. XXXIII.-48

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