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If anywhere, the received aphorism which refuses to separate what does not appear from what does not exist, seems to apply here. “There are many dark places in the field of human knowledge, which even the researches of ages may fail wholly to enlighten; but no one derives a right, from that circumstance, to people them with chimeras and phantoms. They belong to the philosophers of the future, not to the visionaries of the present.” 36 Of land-animals, indeed, the chance of preservation is comparatively very small. Yet even their remains, when the species existed to have remains to bequeath, are often found in extraordinary abundance. Witness the “ivory quarries” of Siberia, or the tusks representing hundred of mammoths fished up by the oyster-dredgers of the Norfolk coast, in the course of a few years of the present century. This even of landanimals; but what of the giants of the sea ? Cetacean petrified teeth and skeletons are found in such quantities “as to constitute a great part of that source of phosphate of lime for which the Red Crag of the eastein counties of England is worked, for the manufacture of artificial manure." 37 Now, keeping in mind, as we have just been warned, that every year is tending to tone down those sharp demarcation-lines which parted system from system in the conception of the earlier geologists, let us steadily contemplate the gigantic reptileclass swarming multitudinous in the seas of the Oolite,
when the gigantic whale-class as yet was not; next survey the Cetacea, tempesting the waters of the Pliocene, when their reptile predecessors had passed away ; and then calmly ask how natural selection will build us a bridge across the chasm ? Did this agency convert a fish-lizard into a porpoise, or extemporize the faculty of giving suck to its young in a reptile “passing through the paths of the sea”? What scope for natural selection, bursting into the group of huge marine mammalia, amidst the monotonous and equable conditions of oceanic life? What creature led up to the whale or the dolphin? The saurians emerge on the geological stage, distinct, sharply defined : sharply defined they disappear, to emerge no more. They are like the bird in the old story, coming out of the winter darkness into the king's feasting-chamber, and passing through its light. and warmth into the winter darkness again.38 And then the sea-sucklers supplant them, not so to pass away. There is an old solution of this vivid apparition of species on the platform of the past. It supposes a voice, not of Natural Law, but of Supernatural Will, which says, Let saurians be! and there are saurians; and, again, Let whales be! and there are whales. Species, on this view, come and go at the bidding of the breath of God. “When Thou hidest Thy face, they are troubled: they die, and are turned to their dust. Again, Thou sendest forth Thy breath, and they are created : Thou renewest the face of the earth."
23. That these successions have not been ruled on the purely competitive principle is one clear lesson of geology. Not always has the battle been to the strong ; not always have the "favoured races” thriven best. Extinction, we are told, is the rigidly exacted penalty that is laid on the laggard in the race of life. And yet, as has been proved by a most laborious induction, throughout the immense Molluscan family, the higher the rank the lower the range: the headless bivalve, with an equal start, has distanced and dispossessed the highly endowed cephalopod. 39 No living stag brandishes an antler comparable to that of the great Irish elk; and the hugest shark now swimming in the seas is a dwarf by the side of its congener of the Miocene, measuring some sixty feet long.40 Fishes take their place in ancient nature in four septs or squadrons, the two first separated from the two last by a prodigious interval ; but, notwithstanding their fierce instincts and their prescriptive occupancy, the cuirassed Placoids and Ganoids give way, and the unwarlike Ctenoids and Cycloids take possession of the field. Physical causes, of themselves, scarcely solve the phenomena of extinction and replacement on so significant a scale ; and the critical unpeopling as well as peopling of the waters throws new and purer light on that study of nature which introduced a Divine Destroyer into the Hindoo Triad. Why are not the saurians, and the monster shark, still scouring our contemporary seas ? Food could never have failed them in so stintless a storehouse, nor climate made war on them, nor rivals exterminated them. And yet they are gone. All that can be said is, that it was necessary to remove them, and -- they are removed. If the Enaliosauria, or the fossil Carcharodon, were living gladiators of the ocean, it could not be so fit a home for their mammalian superiors, and would even be blockaded against man. On seas teeming with these monsters, Arion could not have sailed, nor could the dolphin have disported beside his vessel. But the mammalia have not been left to fight it out with such foes. The animal competition has been modulated into consistency with the unfolding scheme of the Creative Providence. Obedient to no merely physical necessity, defeated in no pitched battle for the sovereignty of the seas, the fossil monsters shrank at another signal from disturbance of that new and higher order for which the appointed time had come, with which their co-presence was clearly incompatible, and which their brute strength, let loose, would infallibly have destroyed.
24. If it be one distinct lesson of the stony archives that the battle is not always to the strong, they teach with at least equal clearness that the race did not start with the weak. It is a vital postulate in all schemes of development-as vital to Mr. Darwin's doctrine as to that of Lamarck, of Oken, or of the “Vestiges” --that precedence is another name for embryotic immaturity and extreme lowness in the scale. Not only must the lower divisions ante-date the higher, for that simply