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THOMAS HENRY HUXLEY.

HUXLEY, THOMAS HENRY, a distinguished English scientist; born at Ealing, near London, May 4, 1825; died at Eastbourne, June 29, 1895. In 1845 he passed his examination at the University of London for the degree of M.B., and in the following year was appointed Assistant-Surgeon to the “Victory." In 1847 he was appointed Assistant-Surgeon to H.M.S. "Rattlesnake," and spent the greater part of the ensuing three years off the coast of Australia. In 1851 he was elected a Fellow of the Royal Society. In 1855 he was appointed Professor of Natural History in the Royal School of Mines; Fullerian Professor of Physiology to the Royal Institution, and Examiner in Physiology and Comparative Anatomy to the University of London. In 1860 he delivered a course of lectures to working-men at the School of Mines, his subject being “The Relation of Man to the Lower Animals.” In 1862 he delivered another course, — "Lectures on our Knowledge of the Causes of the Phenomena of Organic Nature." In 1870 he was elected a member of the London School Board. In 1872 he was elected Lord Rector of Aberdeen University; and in 1873 Secretary of the Royal Society, of which he was chosen President in 1883. In 1881 he was appointed Inspector of Salmon Fisheries; but in 1885 he was compelled by ill-health to resign. In 1892 he was called to the Privy Council.

The following are Mr. Huxley's principal works: "Lessons in Elementary Physiology" (1866); "Introduction to the Classification of Animals" (1869); "Lay Sermons, Addresses, and Reviews" (1870); "Manual of the Anatomy of the Vertebrated Animals” (1871); “Critiques and Addresses" (1873); "American Addresses” (1877); “Physiography: an Introduction to the Study of Nature" (1877); “Anatomy of Invertebrated Animals" (1877); “The Crayfish: an Introduction to the Study of Zoology" (1879); "Science and Culture” (1882); “The Origin of the Existing Forms of Animal Life,” being the Rede Lecture at Cambridge for 1883; “Essays on Some Controverted Questions" (1892); “Evolution and Ethics” (1893). Besides these he has delivered numerous lectures, which have been separately published.

THE ORIGIN OF SPECIES. If we consider, that by far the largest proportion of recorded existing species are known only by the study of their skins, or bones, or other lifeless exuvia ; that we are acquainted with none, or next to none, of their physiological peculiarities, beyond those which can be deduced from their structure, or are open to cursory observation, and that we cannot hope to learn more of any of those extinct forms of life which now constitute no inconsiderable proportion of the known Flora and Fauna of the world : it is obvious that the definitions of these species can be only of a purely structural or morphological charactér." It is probable that naturalists would have avoided much confusion of ideas if they had more frequently borne the necessary limitations of our knowledge in mind. But while it may safely be admitted that we are acquainted with only the morphological characters of the vast majority of species -- the functional, or physiological, peculiarities of a few have been carefully investigated, and the result of that study forms a large and most interesting portion of the physiology of reproduction, 9. The student of Nature wonders the more and is astonished the less, the more conversant he becomes with her operations; but of all the perennial miracles she offers to his inspection, perhaps the most worthy of admiration is the development of a plant or of an animal from its embryo. Examine the recently laid egg of some common animal, such as a salamander or a newt.' It is a minute spheroid in which the best microscope will reveal nothing but a structureless sac, enclosing a glạiry fluid, holding granules in suspension. But strange possibilities lie dormant in that semi-fluid globule. Let a moderate supply of warmth reach its watery cradle, and the plastic matter undergoes changes so rapid and yet so steady and purposelike in their succession, that one can only compare them to those operated by a skilled modeller upon a formless lump of clay. As with an invisible trowel, the mass is divided and subdivided into smaller and smaller portions, until it is reduced to an aggregation of granules not too large to build withal the finest fabrics of the nascent organism. ' And, then, it is as if a delicate finger traced out the line to be occupied by the spinal column, and moulded the contour of the body; pinching up the head at one end, the tail at the other, and fashioning flank and limb into due salamandrine proportions, in so artistic a' way, that, after watching the process hour by hour, one is almost involuntarily possessed by the notion, that some more subtle aid to vision than an achromatic, would show the hidden artist, with his plan before him, striving with skilful manipulation to perfect his work.. ... As life advances, and the young amphibian ranges the waters, the terror of his insect contemporaries, not only are the nutritious particles supplied by its prey, by the addition of which to its frame growth takes place, laid down, each in its proper spot, and in such due proportion to the rest, as to reproduce the form, the color, and the size, characteristic of the parental stoek ; but even the wonderful powers of reproducing lost parts possessed by these animals are controlled by the same governing tendency. Cut off the legs, the tail, the jaws, separately or all together, and, as Spallanzani showed long ago, these parts not only grow again, but the redintegrated limb is formed on the same type as those which were lost. The new jaw, or leg, is a newt's, and never by any accident more like that of a frog. What is true of the newt is true of every animal and of every plant; the acorn tends to build itself up again into a woodland giant such as that from whose twig it fell; the spore of the humblest lichen reproduces the green or brown incrustation which gave it birth ; and at the other end of the scale of life, the child that resembled neither the paternal nor the maternal-side of the house would be regarded as a kind of monster.

So that the one end to which, in all living beings, the formative impulse is tending - the one scheme which the Archæus of the old speculators strives to carry out, seems to be to mould the offspring into the likeness of the parent. It is the first great law of reproduction, that the offspring tends to resemble its parent or parents, more closely than anything else. 1. Science will some day show us how this law is a necessary consequence 'of the more general laws which govern matter ; but, for the present, more can hardly be said than that it appears - to be in harmony with them. We know that the phenomena of vitality are not something apart from other physical phenomena, but one with them; and matter and force are the two naines of the one artist who fashions the living as well as the lifeless. Hence living bodies should obey the same great laws as other matter - nor, throughout Nature, is there a' law of wider application than this, that a body impelled by two' fordes

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