Play wanton, every moment, every spot."
Thickets of tall reeds rose out of the water, with stems massive as those of our forest-trees, encircled at regular distances by wreaths of pointed leaflets, and bearing on their summits club-like catkins. Far away, the distant hills lay shaggy with pine-woods, and nursed in their solitudes the springs and rivulets that worked a devious course through forest, and glen, and valley, until, united into one broad river, they crept through the rich foliage of the delta and finally passed away out to sea, bearing with them a varied burden of drift-wood, pine-trees from the hills, and stray leaves and cones from the lower grounds.
How different such a scene from that now presented by the very same areas of country! These old delta lands are now our coal-fields, and have exchanged the deep stillness of primeval nature for the din and turmoil of modern mining districts. In these ancient times, not only was man uncreated, but the earth as yet lacked all the higher types of vertebrated being. None of the animals that we see around us existed then; there were no sheep, nor oxen, horses, deer, nor dogs. Neither were the quadrupeds of other lands represented; the forests nourished no lions or tigers, no wolves or bears, no opossums or kangaroos. In truth, the land must have been a very silent one, for we know as yet of no animated existence that could break the stillness, save perchance some chirping grasshopper, or droning beetle, or quivering dragon-fly. No bee hummed along on errands of industry; it is doubtful, indeed, whether honey-yielding flowers formed part of the carboniferous flora; no lark carolled blithely in the sky, nor rook croaked among the woods. All was still; and one might, perhaps, have stood on some of those tree-crested islets, and heard no sound but the rippling of the water along the reedy and sedgy banks, and the rustling of the gloomy branches overhead.
To one who muses on these bygone ages it is no unimpressive situation to stand in the midst of a large coal district and mark its smoking chimneys, clanking engines, and screaming locomotives, its squalid villages and still more squalid inhabitants, and its mingled air of commercial activity, physical wretchedness, and moral degradation. It is from such a point of view that we receive the most forcible illustration of those great changes whereof every country has been the scene, and which are so tersely expressed by one who has gazed on the revelations of geology with the eye of a true poet—
"There rolls the deep where grew the tree.
O earth, what changes hast thou seen!
There where the long street roars, bath been
The stillness of the central sea."
But the lifelessness of the carboniferous forests was amply compensated by the activity that reigned in river, lagoon, and sea. Coral groves gleamed white beneath the waves, fishes of many a shape disported in stream and lake, and the bulkier forms, armed in massive plates of bone, ascended the rivers or haunted the deeper recesses of the open sea. In some beds of rock the remains of these various animals lie crowded together like drifted tangle on the sea-shore, and the whole reminds us of a vast cemetery or charnel-house. The bones lie at all angles, many of them broken and disjointed as though the owner had died at a distance, and his remains, sadly mutilated on the way, had been borne to their last resting-place by the shifting currents; others lie all in place, covered with their armature of scales, as though the creature, conscious of approaching dissolution, had sought out a sheltered nook and there lain down and died. It is not uninteresting or uninstructive to tract; out in an old quarry stratum above stratum, each with its groups of once living things. I know of few employments more pleasant than to sit there, amid the calm stillness of a summer evening, when the shadows are beginning to steal along the valleys and creep up the hill-sides, and in that dim fading light to try in fancy to clothe these dry bones with life, to picture the time when they lived and moved in the glassy depths of lakes and seas, or amid the solitudes of jungles and forests, and so to spend a pleasant hour in reverie, till roused at last by the vesper song of the lark, or the low meanings of the night wind as it sighs mournfully through the woods.
The study of fossil animals embraces a much greater range of subject than that of fossil plants. The fauna of any particular geological formation, that is to say, its embedded animal remains, for the most part vastly exceeds in number its flora, or vegetable remains, and is likewise usually better preserved. About the nature and affinities of several tribes of fossil plants there hangs an amount of uncertainty which renders them a dubious guide to the climatal and other conditions of the period and locality in which they lived. Generic distinctions among living plants often rest on the character of those parts which are the most perishable, such as flowers and seed-vessels. These delicate structures we, of course, can hardly look to find preserved in the rocks, and we have in place of them only detached leaflets, twigs, branches, and stems, often sorely mutilated in outward form, and presenting no trace of internal organization. But the tribes of the animal kingdom have, for the most part, harder frameworks. The minute infusoria, which by their accumulated remains help to choke up the delta of the Nile, and swarm by millions in every ocean of the globe, have their silicious or calcareous shells so minute that Ehrenberg has estimated a cubic inch of tripoli to contain forty-one thousand millions of them. The polypi have their internal calcareous skeletons, which abound in all the older limestones, and form the coral reefs of the present day. The mollusca, too, though, as their name imports, they have perishable bodies, are yet, in most cases, furnished with hard calcareous shells, that indicate by their various modifications of form and structure, the character of the animal that lived within them. They are found in all the formations from the earliest upwards, and as they vastly exceed in numbers all the other classes with which the geologist has to deal, they form the larger part of that basis of evidence from which he interprets the past history of organized existence. Hugh Miller loved to talk of them as the "shell alphabet," out of which the language of palæontological history should be compiled. The vertebrata, too, all have their hard skeletons, easily capable of preservation, whether it be in the form of the massive exo-skeleton of bone that characterized the older ganoidal fishes, or the compact endo-skeleton of the reptiles and mammals. A greater amount of attention is, therefore, due to the study of fossil animals, since they thus not only far exceed fossil plants in number, but possess a higher value as evidence of ancient physical conditions.