in unison with those on our planet, are like two tuning-forks set at concert pitch; and, awaking human response, we say"The mighty synthesis is proof that God is One."

The fact is capable of further development. Every process of initial life is the prophecy of an advanced life. From inorganic world-elements arise all organisms. A germ of life, even before it is large enough to be seen, contains in itself a special endowment-the invisible constructive potentiality of every organ. The first steps of life are in a path common to all, but quickly turn aside; and, by way of its own, every living creature arrives at a peculiar destination. In plants we have production and reproduction; in animals self-perception, self-control, and motion; in man self-consciousness, will, and moral power; the whole wrought by a deeper and more far-reaching energy than science can find any satisfactory explanation of, all the vital actions being, as the oscillations of a needle, moved by unseen influences from within and without.

The bringing forth of kind after its kind, that process by means of which new individuals are produced, and perpetuation of the species is ensured, presents many marvels. Some of the lowest and smallest animals are of both sexes,-"hermaphrodite." Others are non-sexual, and the young are produced by gemmation or fission.

Hermaphrodites are double-sexed individuals. Many plants, garden-snails, leeches, earth-worms, and various other worms, are of this order.

Gemmation (gemma, a bud) is the production of young by a bud or buds, usually on the outside, but sometimes on the inside of an animal. Thus new life is formed, which may either be completely separated from the parent, or remain connected with it, and form a stock or colony.

Fission (findo, I cleave) is the production of new beings by the cleavage or division of a primitive zoöid into two or more parts. This fission, occurring frequently, reproduces by tolerably rapid multiplication. An internal fission, or swarming, causes the death of the parent, and produces a vastly multiplied offspring.

In the Vertebrata and all high kinds of life, reproduction is

Reproductive Elements.

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always sexual, and the sexes are in different individuals. Most are oviparous, producing eggs from which the young are developed; but the higher vertebrates bring forth their young alive.

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Until recent times it was thought that in every species the successive generations were alike, this is called homogenesis. It is now proved that in many plants, and in numerous animals, the successive generations are not alike, this is called heterogenesis. The progeny, differing from the parents, produce others, like themselves, or like their parents, or like neither, but, eventually the original form reappears. There is no scientific explanation of this; we can only ascertain the varying order of it as seen in different creatures. In all cases

of sexual or gamogenesis, there is reason to think that even among the lowest Protozoa, a fusion of two individualities is the process from which results the germ of a new series of individuals; so that in those humblest forms, which have no differentiation of sexes, the union is not of sperm-cells and germ-cells of the same individual, but union between those of different individuals. The power is mysterious, and the more so that the cells, or cradles of life, are not greatly specialized in mechanism, they rather seem unspecialized; yet, if there is no special arrangement to secure conditions of existence for different modes of multiplication, it is certain that arrangements which secure these special ends do continually establish themselves. No visible or mechanical property explains the profound distinction between the male and female reproductive elements; but in the union of these begins, at once, or on the arrival of favourable conditions, a new series of developmental changes; a process of cell-multiplication is set up, and the resulting cells aggregate into the rudiment of a new organism. The force by which two adjacent atoms attract or repel each other, their mode of exercise and law of variation, are incomprehensible. Every effort to understand the essence and origin of life leading to the Great Unknown, from whom all life has sprung, according to the patristic interpretation,- yέYOVEV Év αúr wn Jno. i. 3, 4).

We may now briefly summarise some of the principal

results to be deduced as to the succession of life on the earth. The creation of marine animals was first, and the first living creature that we know of is the Eozoön. What did Eozoön live on? Small animals with shells of carbonate of lime; otherwise, how was its vast mineral skeleton obtained? Other creatures existed even more humble than the food of the Eozoön, and it is not unworthy of consideration whether primal life did not exist when the waters were very warm. Even now the coral luxuriates in the equatorial temperature of 90° and more. There are Infusoria which flourish in warm springs, and the life cannot be got out of a germ by simple boiling. "The waters swarmed a swarm," not that the causality was in the waters, but in the creative energy or word, "Let the waters bring forth abundantly the moving creature that hath life (es sollen wimmeln die Wasser vom Gewimmel)." This life is and has been so abundant that the earliest limestones of the globe teem with the evidence of former minute life, and this is the case with every limestone down to those now forming in the abyss of the ocean. Ehrenberg discovered that in slate of close texture, 41,000 millions of these infinitesimal creatures were contained in a cubic inch. Coral animals were introduced, and since have been found efficient workers; but the deep seas of old, and the depths of modern oceans, both assert that the first workers are pre-eminent. This dawn of life was by a long, slow process; nevertheless, sponges, lingulæ, orchids, trilobites, sea-worms, with many other creatures representing five of the great sub-divisions of animals-Protozoa, Coelenterata, Annuloida, Annulosa, Mollusca are found in the very old rocks.

These old rocks have rain indentations, ripple-marks, and shrinkage cracks, which prove that the actions of rain, of tide, of sun, were the same then as now. "Were there no land animals to prowl along the low tidal flats in search of food? Were there no herbs nor trees to drink in the rains and flourish in the sunshine? If there were, no bone nor footprint on the shore, no drifted leaf nor branch, has yet revealed their existence to the eyes of geologists." We may, however, be sure that the creative process was not stayed on the land for 1 "The Story of the Earth and Man," p. 32: J. W. Dawson, LL.D.

full development of life in the sea, but that birds and animals lived much earlier than the earliest known fossils indicate. "It is even possible that in a warm and humid condition of the atmosphere, before it had been caused to rain upon the earth,' and when dense 'mists ascended from the earth and watered the whole surface of the ground,' vegetation may have attained to a profusion and grandeur unequalled in the periods whose flora is known to us."1

In the Upper Silurian period we find fishes, not of large size, nor abundant, of two separate types. Ganoids, represented at the present day by the Sturgeons, the Gar-pikes of North America, and a few other less familiar forms; Placoids, or shark-like fishes. These two groups are both distinct and highly organised. Ordinary bony fishes were not introduced until comparatively recent time. In the Devonian era was a vast increase, and it became preeminently the age of fishes. New lands were upheaved, with extended muddy and sandy flats around them; shoals of fishes, some very remarkable, swarmed in shallow seas and estuaries. Among the most ancient and curious, appearing also in the Upper Silurian, are the Pteraspis, a tribe of mailed fishes, akin to the Cephalaspis, or buckle-head; its broad flat head being rounded in front, and prolonged at the sides into two great spines. Another group of small fishes, represented by the Pterichthys, had two strong bony fins at the sides, which served for swimming, for defence, for creeping on and shovelling up the mud at the bottom of the sea. There were great fishes with strong cutting double-rowed teeth; wrinkle-scale, bone-scale, and star-scale; and the huge Dinicthys, having head more than three feet long and eighteen inches broad, two long sabreshaped tusks, each a foot long, and a body about thirty feet in length. The Carboniferous fish were numerous, great Ganoids, with sharp bony scales and sharp-edged or conical teeth, haunted the creeks and ponds of the coral swamps. Multitudes of sharks with sharp-edged trenchant teeth; and one species allied to the existing Port Jackson sharks their mouths paved with flat teeth for crushing shells; sought prey near shell banks and coral reefs. The "The Story of the Earth and Man,” p. 32 : J. W. Dawson, LL.D.

broad-snouted, plate-covered, and mud-burrowing crustaceans, the Trilobites, are lost in this period. In the Cretaceous period are found the first examples of the great group of Bony Fishes, or Teleosteans, comprising the great majority of forms now existing. The main forms of fishes characterising the Eocene are like those which predominate in existing Those of the Miocene were abundant, and some of the species attained gigantic dimensions.

seas.

The amphibious part of creation are the link which joins land animals and fish. There are fish which have the habit of leaving the water for a forage on land. Let their fins be lengthened and moderately altered in shape, the tail modified, and we shall have some of our amphibious animals almost to the life, of which are many high groups in the Carboniferous deposits. There were little reptiles of the coal forests. The most fish-like were the Archegosaurus, with large heads, short necks, permanent gills, feeble limbs, and strong tails for swimming. They were of higher order than fish, in possessing lungs and feet. The first undoubted remains of true reptiles are found in the Permian deposits. From these creatures are two lines of ascent-one leading to gigantic crocodile-like animals; the other to small delicate lizard-like species, dwelling on land and feeding on insects. "Imagine a little animal, six or seven inches long, with small short head, not so flat as those of most lizards, but with a raised forehead, giving it an aspect of some intelligence. Its general form is that of a lizard, but with the hind feet somewhat large, to aid it in leaping and standing erect, and long flexible toes. Its belly is covered with long scales, its sides with bright and probably coloured scale armour of horny consistency, and its neck and back adorned with horny crests, tubercules, and pendants. It runs, leaps, and glides through the herbage of the coal forests, its eye glancing and its bright scales shining in the sun."1 This is a picture of the as yet earliest known lizard, the Hylonomus, the oldest animal which has a fair claim to be called reptile. In the Permian rocks are highly organised lizards with socketed teeth, well-developed limbs, long tails, and biconcave vertebra. They connect the Carboniferous

1 "The Story of the Earth and Man." J. W. Dawson, LL.D.