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spermous kinds, abounded in the cretaceous strata of America and Europe. Probably, preceding all these, a microscopic vegetation universally existed. It is a beauty, and not defect, that the simple formula of words given in the Bible contains and describes lowest and highest products, the earliest and latest vegetable life.

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Who will say that the modern scientific classification—

Phænogams or Flowering Plants,

I. Plants with one seed lobe.

{1. Plants with one seed lobe.

Cryptogams or Flowerless Plants, 3. Vascular Plants for the most part.

4. Purely Cellular plants.

is simpler, more comprehensive, intelligible and beautiful for ordinary people than the ancient words, roughly translated, grass, herb, plant, tree?

We may now summarise, in briefest possible manner, the succession of vegetable life on the earth. The groups did not come into existence at once; in the main, the lower groups appeared first, and the higher groups last, substantially in accord with the Scriptural statement. The earliest known vegetation "consisted principally of the lowly organised Cryptogamous or flowerless plants. The Mesozoic formations, up to the Chalk, are especially characterised by the nakedseeded flowering plants,-the Conifers and the Cycads; while the higher groups of the Angiospermous Exogens and Monocotyledons characterise the Upper Cretaceous and Tertiary Rocks."1 The process was slow and gradual, and, for the most part, without sudden breaks, proceeding to a greater or less extent, by way of evolution; so that many existing species are the modified descendants of fossil forms, even as those were derived from pre-existent forms. At the same time, there are facts which prove the existence of some law of a deep and far-reaching character, by which alone can be explained the constant introduction, throughout geological time, of new forms of life; for example, the wonderful Dicotyledonous flora of the Upper Cretaceous period bursts into view without any prophetic announcement from the older Jurassic.2 This is yet more specially the case with animal life. So far

1 "The Ancient Life History of the Earth,” p. 371: H. Alleyne Nicholson. 2 "The Ancient Life History of the Earth," p. 373: H. Alleyne Nicholson.

Plants without Sunlight?

191

as we know, the Graptolites and Trilobites had no predecessors, and have no successors. Insects appear suddenly in the Devonian and the Arachnides and Myriapods in the Carboniferous strata, under "well differentiated and highly specialised types." Nor is this all. There are various groups, and some of them highly organised, which continue almost unchanged, and certainly unprogressive, throughout geological time. They indicate that under given conditions, at present unknown, a life-form may subsist for an almost indefinite period without any modification in its structure. One cannot but admire, in connection with this continuance of work "by some orderly and constantly-acting law of modification and evolution," and in connection with "the constant introduction throughout geological time of new forms of life," which "have no known predecessors and have no successors," the scriptural use of the word Day. Day, in its minuteness, reduces the initiation of living things to exceeding brevity of time; and day, in its expansiveness, comprehends innumerable ages; so that whether we think of the constant introduction of new forms, or of the continuous operation by which old forms are modified, both are wrought in the Day of God.

Pursue the inquiry :—

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i. Is it possible that plants were produced under a denser, cloudier moisture and more disturbed atmosphere than the present?

ii. Did plants precede animals?

iii. Were plants of Divine origination?

i. As to the origination of plants without sunlight, we must at once admit that it is simply impossible for the cooled earth to have been without the sun as luminary, and without alternate day and night. Tidal marks are found in the lowest rocks (azoic), and thus we know, comparatively early, of the moon. It is also to be taken as a fact that the sun, like the earth, was formerly hotter than at present. "We can imagine that one effect of its heat was to throw off from its surface such enormous clouds of absorbing vapour, which cooled as they left the sur

1 "The Ancient Life History of the Earth," p. 373: H. Alleyne Nicholson. "The Ancient Life History of the Earth," p. 372: H. Alleyne Nicholson. 3 "The Ancient Life History of the Earth," p. 373: H. Alleyne Nicholson.

face, that the effective amount of radiation reaching the earth might not have been greater than at present. So it is possible to conceive a uniformitarian state of radiation from the sun, accounting for it by saying that when the sun was hottest and was radiating the most, it was simultaneously raising the greatest amount of obstructions to the propagation of radiations from its surface. A similar argument might, of course, be devised with reference to the greater amount of vapour which increased solar radiation would raise to be condensed in the earth's atmosphere."1 Hence it is at least not improbable that the photosphere might be partially obscured by non-luminous matter, and that a dense cloudy atmosphere surrounded the earth. In any case, the earth long ago was an incandescent mass, itself as a sun; and only as the earth cooled and darkened would the sun and moon be revealed as rulers of day and night.

Plants, as a class, contain little nitrogen, and are dependent on solar rays for their vital activities; but there is, at least, one marked exception. Of a considerable group, the Fungi, many members, if not all, can live and grow in the dark. Moreover, in great depths of the sea unpierced by light, in dark caves, and in many places of gloomy obscurity, there is vegetable life. The light, however, comes from heat; is a transformation of heat from the sun and from the earth. The seed of a plant, buried in the damp earth, grows by the integration of adjacent nutritive materials; the energy effecting this union is, or is by, the undulations caused by warmth of the soil. Diminish the warmth, as in winter, and the seed will not grow. As to the sun's action, the slower undulations, dark waves, not seen, penetrate the soil, set in motion the atoms of the rootlet, and enable them to shake hydrogen atoms out of equilibrium with oxygen atoms. Such is the operation at the root.

This helps us to conceive the possibility and reality and nature of the earliest vegetation: rudimentary sporules, with neither radicle nor plumule, possessing some resemblance to imperfect plants that are counted of recent formation.

So soon as plants with delicate green stalks tipped with 1 "Recent Advances in Physical Science," p. 174: P. G. Tait, M.A.

Plants Preceded Animals.

193

leaflets are to be formed, there must be those rapid waves of the sunbeam, known as light and actinism. These enable the leaflets to decompose the carbonic acid of the atmosphere, by communicating their motor energy to the atoms of chlorophyll, so that they can dislodge adjacent atoms of carbon from the carbonic acid in which they are suspended.

Hence, whether viewed popularly or scientifically, we have a great truth the Energy preparing those germs developed in the earliest manifestations of vegetative force was in operation even when the sun and earth abode in cloudy tabernacles. We can well understand that Moses might have a moral purpose in view, that to check the idolatry of sun-worshippers he would wish to state that life was of God in its origination, not by the sun, before the sun; but that his so-called rough, unscientific account should agree with the latest scientific verity -that life-energy, indeed all energy, is a product and transformation of pre-existent energy-can by no means be owing to his wisdom; it must be attributed to that power which we name "Divine Inspiration."

ii. Did plants precede animals?

Relics of animals are found in the oldest rocks, with the lowest and earliest known vegetable forms. It is possible, barely probable, that the primal forms of life have been preserved in some primitive fossils. From the layers of crystalline charcoal (graphite), and crystalline limestone (marble), found in the metamorphic rocks, we conclude that vegetable and animal life existed side by side in earlier times. Certainly, animal life did not wait till vegetation was perfected; the lower forms soon appeared, and grew contemporaneously with plants, both advancing till land and sea were replenished. Plants, as a class, exhaling oxygen, and animals, respiring carbonic acid, are necessary to one another; nor can the highest forms of either exist without the presence of both in the earth plants building up themselves with the carbonic acid given out by animals, and animals inspiring the oxygen which plants exhale. The balance of the gases and elements is thus beneficially maintained by the antagonistic compensating actions of the two kingdoms, whose continuous adjustment of internal relations to external relations necessitates

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and comprehends all the activities of vegetable and animal life.

Finding relics of both in the oldest rocks; that both are needed for the highest forms of either to exist; and that, viewed in their earliest forms, the animal arises as the plant; for, so far as form and substance can be ascertained, they are not separable; the primordial cell of a nettle and the first germ of man being undistinguishable from one another, even by the aid of a powerful microscope, we might conclude that their nature is the same. Nevertheless, they have not the same birth-day, do not live after the same manner, nor upon the same substance. The following twofold fact proves that animals and plants are essentially distinct and wide apart. Plants can form protoplasm,—that is, support themselves by means of inorganic substances; animals cannot. Carbon and oxygen unite to form carbonic acid, hydrogen and oxygen produce water, nitrogen and hydrogen give rise to ammonia. These are all lifeless; on these a plant lives and thrives, but an animal famishes and dies. The animal's highest feat of constructive chemistry is to raise dead protoplasm to a higher form of living protoplasm; but plants form protoplasm of that which is not protoplasm, even from carbonic acid water and ammonia. They, and they alone, build up that matter of life which is the vital substance of the universe. We can hardly think that Moses was accurately acquainted with the discoveries of modern chemical science; nevertheless, he records that plants preceded animals.

iii. Were plants of Divine origination?

The Power by which matter organises itself, grows into shape, and assumes definite forms in obedience to the definite actions of energy, is a manifestation of that great Unknown whom all phenomena reveal; otherwise, the molecules themselves are creators; and we have no end of little gods. The celebrated Robert Boyle regarded the universe as a machine -a machine may be defined as an organism with life and direction from outside. Thomas Carlyle prefers regarding it as a tree-a tree may be defined as an organism with life and direction within. We, in a degree, may adopt both conceptions, for both imply the interdependence and harmonious

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