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ments, carbon, hydrogen, oxygen, and nitrogen, in very complex union." Thus there is "a general uniformity in the character of the Protoplasm, or physical basis of life, in whatever group of living beings it may be studied."-HUXLEY'S Lay Sermons, p. 142.

*VIII.

NUMBER OF SPECIES OF INSECTS. Page 193.

Professor Huxley mentions that "Gerstæcker in the new edition of Broun's 'Thier-Reich' gives 200,000 as the total number of species of Arthropoda." In this connection Mr. McLauchlan, when claiming that there are 200,000 species of Insects, adds, "In one order alone (Coleoptera) it is estimated that 80,000 species have been described."-Nature, xv. p. 275.

IX.

FERTILIZATION OF FLOWERS BY INSECTS. Page 170.

Dr. Hermann Müller's Observations are described in Nature, vol. xiv. p. 175; vol. xv. pp. 317, 473; vol xvi. pp. 265, 507.

X

ANTS. Page 192.

Mr. McCook's Observations are summarized in Nature, vol. xvii. p.

433.

XI.

LIKENESS OF THE APE'S BRAIN TO THE HUMAN BRAIN. Page 225.

The close resemblance of the brain of the ape to that of man, has been held to prove that the ape comes next to man in intelligence. But the facts bearing on this suggestion are fitted to occasion serious perplexity to its upholders. First stands the resemblance of bodily structure as largely explaining similarity of brain. The results of electric stimulation of the monkey's brain lend additional force to this consideration. Again, facts are wanting to support the claim for superior intelligence in behalf of the monkey and ape. The habits of the ape in its natural state afford little evidence of an encouraging kind. The ape gathers together a few sticks for a nest, in comparison with which the work of very small birds presents marvels of architecture. And nest-building seems the highest evidence gathered from the natural habits of the animal, when we compare it with leaning the back against a tree for rest, or staunching the blood of a wound. In the captive state the ape gives no such evidence of superior intelligence as the similarity of its brain to the human, would lead us to expect, if brain structure afford the test of intellectual power. Even after allowance has been made for sudden transition from the wild state to the captive, the evidence of capability does not appear which the theory requires. The highest results reached by training monkeys, do not support a claim for intellectual superiority. These are mainly forms of mimicry, generally inferior to the efforts of some other animals.

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Add to these considerations the evidence as to the singular intelligence shown by ants, and the theory which measures intellect by brain structure is placed at a great disadvantage. Whether science may not ere long point to some theory of mind connected with animal existence must be matter of uncertainty. If, however, the easy and familiar operations of our own intelligence are analyzed and classified; and if a statement of the ascertained functions of the brain is laid alongside, it will appear that nothing known to us in the action of brain, can supply a science of the operations of the human mind.

XII.

THE LARGE SIZED OR MULTIPOLAR CELLS. Page 257.

On the functions of the large sized cells, it seems desirable to add a few words as to the direction in which evidence as to their functions actually points. For this purpose, a further quotation is desirable, referring to the number of fibres or processes passing off from these large cells, distinguishing those which branch out into a fine net-work, and those which pass directly to a nerve fibre. "One at least of the processes of a multipolar nerve cell does not branch, but becomes directly continuous with a nerve fibre, and has been named the axial-cylinder process."-Professor Turner's Human Anatomy, i. 201. This taken with the facts given in Lecture VII, seems to favor the conclusions, (1) that the large cell spreads nerve energy through the tissue of the brain, while each has at least

one direct line of communication with the system of nerve fibres; (2) that the large cell has intimate and extended relations with the motor system.

XIII.

THE CONCEPTION OF DUTY. Page 273.

"Duty! Thou great, thou exalted name! Wondrous thought that workest neither by fond insinuation, flattery, nor by any threat, but by merely holding up thy naked law in the soul, and so extorting for thyself always reverence, if not always obedience,—before whom all appetites are dumb, however secretly they rebel,—whence thy original?"-KANT's Critique of Practical Reason.

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