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order to hand down important events to posterity, so has nature given in the fossils a sign to geologists which enables them to estimate the comparative age of strata whose boundaries and order cannot be calculated with certainty from the condition of the rocks alone, whether they be of clay, chalk, or sand. A German savant—Naumann—has compared fossils to inscriptions, and says that as the Punic, Greek, or Roman inscriptions teach the antiquarian that monuments are Carthaginian, Greek, or Roman, so the geologist may ascertain from the presence of certain fossils at what period in the earth's history the separate strata were deposited. Without this aid, geology would not have been able in our time to ascertain accurately and surely so much about the history of the earth in the early ages, long before the beginning of man's history.

But palaeontology has become important to natural science in another way also. It teaches us about plants and animals, which for the most part no longer exist, but which have existed, on the earth. The history of the present animal and vegetable world is supplemented by that of the flora and fauna of the primaeval world; and natural history thus becomes complete, because it embraces the two great classes of organic beings, those which still exist and those which are extinct . Of course in many of the fossils, parts only of the plants and animals have been preserved, usually the harder, more solid parts; but science has been able by means of careful and comprehensive comparisons to reconstruct with tolerable accuracy the whole form of the animal or the plant, even from the scanty remains which are found.1

1 Vogt, Lehrb. der Geol. ii. 604. Pfaff, Schopfungsgesch. p. 615.

I may mention here1 that one of the results of the more thorough investigations in this province has been to show how erroneous is the belief that the primaeval fauna and flora differed generally from the present fauna and flora, in being of a gigantic and grotesque character. This was much insisted on formerly, and the theory may still be found in the popular expositions of some superficial writers, who prefer what is wonderful to what is true. No doubt primaeval plants and animals of this description are found; but it is by no means generally or universally the case. Strange forms occur among the petrified remains; for instance, among the reptiles we find various saurians, or species of flying and swimming lizards, as the plesiosaurus and the pterodactylus;2 and among the mammalia, the

1 Cf. Wagner, Geseh. der Urwelt, i. 378; Natur und Ofenbarung, iii. 462. Fraas, Vor der Siindjluth, p. 59. Giebel, Tagesfragen, p. 107, "Die Wunderthiere der Vorwelt."

* "As Cuvier said, the plesioeaurii are perhaps the most striking inhabitants of the earlier world. They possessed the head of a lizard and the teeth of a crocodile, an enormous serpent-like neck, the tail of an ordinary mammal, the ribs of a chameleon, and the webbed feet of a whale. The animal probably swam like a swan with its neck bent in the shape of an S, and lived on fish like the ichthyosaurus. We know this from the examination of the coprolites, which contain the scales and bones of fish which formed the food of these animals." Noggerath, Ges. Natura, iii. 266. Fraas, p. 241. "It was formerly uncertain whether the pterodactylus was a mammal, a bird, or a reptile; now it is known to belong undoubtedly to the last class. The head is large, the mouth filled with long spiky teeth, the neck long and thick, the body short and weak, the shoulder-blades very strong, the forearm short and tolerably thick, the bone of the lower part of the arm more than twice as long as the upper bone. Attached to the former by some small metacarpal bones is the most extraordinary hand in the whole animal world; it consisted of four thin claw-like fingers, to which was added one enormously long, thick, sword-like finger, which alone was about as long as the neck and body put together." Noggerath, p. 269. Fraas, p. 297. This finger was used for stretching out the bat-like skin, which, however, was not intended for flying, but as a kind of parachute when the animals, like our flying dinotherium giganteum ;1 but strange forms exist also in the present da)-,—I may mention the ornithorhynchus, ant-eater, sloth, flying dragons, and as a rule they were just as rare formerly as they are now. The same holds good as to the size of the organisms. The present equisetaceae or horsetails are usually hardly a foot, and at most four feet high, and they are about the thickness of one's thumb; and our lycopodiaceae or mosses consist of tendrils with thin branching stems, which wind along the ground between the heather; now we find petrified equisetaceae which are as thick as one's arm or leg, and lycopodiaceae which were trees of a considerable size. But then we find nothing in the petrified plants corresponding to our oaks, palms, and other giant trees; there is no instance known in which a fossil tree of more than four feet in diameter has been found. And if we are told of the colossal ichthyosaurus, dinotherium, and others among the fossil animals,—the mammoth, or elephas primogenius, was not materially larger than the present Asiatic elephants,—we can show that our seas hide in their depths gigantic kinds of whales, which exceed

dragons, threw themselves from a height on to the ground or low branches of trees. The pterodactyls were small animals. Cf. Giebel, Op. ext. p. 117.

1 It had, what is the case with no other animal, in the lower jaw two large teeth, bent downwards and backward. It is supposed that it lived mostly in island seas and rivers, that it dragged out the roots and plants from the bottom of the water with its tusks, and then conveyed the food to its mouth by means of the trunk We need not discuss whether, as some people think, it used the tusks as a weapon and also as an anchor; so that the animal could fasten itself to the shore by them while it floated on the water, and so sleep and breathe without danger, or could draw itself up on to the land with more ease. Cf. Noggerath, p. 288. Of course the description of these animals given here rests partly on mere conjecture.

in size all the types of fossil fauna.1 Generally speaking, although many of the giant forms of the primaeval world do not exist in the present condition of things, yet their place has been filled by other gigantic shapes, so that the present state of nature is not inferior to the earlier state in respect to the size of the organic forms. On the other hand, animals of middle-sized and small, even microscopic dimensions are not wanting in the fossil fauna.2

1 The mammoth (according to some the name is corrupted from the Behemoth of the Bible, according to others from the Russian " mammont") did not exceed the largest living elephant in size; on the contrary, it hail a smaller head, weaker chest bones, and shorter, thicker legs. When we are told that fossil tusks of 12 feet long and more are found, it must be remembered that the tusks of elephants grow on till the animal dies, no matter how great its age is; and as the mammoth was neither tamed nor hunted for the sake of ivory, it could grow on, and reach the advanced age which was natural to it much oftener [than our elephants do. (Fraas, p. 410.) The body of the northern whale is sometimes 66 feet long, and at the fins reaches the immense size of 40 feet in circumference; the body of the sperm whale is sometimes 75 feet long and 88 feet round; and lastly, the fin-backed whale exceeds all other animals in length, and is 100 feet long by 10 round. We look in vain for these monsters of the deep in the earlier periods of creation. . . . The largest crocodiles are on an average 20 to 80 feet long. This was supposed to be too little for the fantastic giants of the primaeval world. When the bones of the iguanodon were first found, its length was immediately reckoned to be 160 feet; R. Owen reduced it to 28 feet, of which 3 were for the head, 12 for the body, and 13 for the tail. The hylaeosaurus and megalosaurus are often supposed to reach a length of from 60 to 80 feet; and the size and massive form of their separate bones astound all who are not familiar with their organization; but the massive form of a single bone does not determine the whole size of the body. Owen's trustworthy computation puts the length of the hylaeosaurus at most at 25, and the megalosaurus at 30 feet. These are the most colossal land saurians; the longest ichthyosaurus did not attain to more than 30 feet. Giebel, Op. eit. p. 128. It is generally supposed that the dinotherium was from 18 to 20 feet long.

* I am able to refute the theory that the primaeval world only produced gigantic animals, and that no vertebrate as small as the present ones existed, by adducing a species of sorex from the Molosse formation at Mainz, which is smaller than the smallest existing shrew mouse, and that is saying a great deaL H. v. Meyer, Ueber die Reptilien, etc., p. 111. Many deposits several hundred feet thick in the chalk strata have been

Yet one more question: Do fossil men, or remains of men, exist? If by fossils we mean the remains of organic beings which are found in a more or less altered condition in the strata of the earth's crust, this question must undoubtedly be answered in the affirmative. For human remains have been repeatedly found in the same place and in the same condition as the fossil bones of animals; for instance, a whole skeleton was found in a limestone stratum on the coast of Guadeloupe.1 The formation of limestone strata is going on still, so that it does not follow that any deposit found in them is of ancient date; and in fact the fossil man of Guadeloupe has been proved to be at most a few centuries old.

But the word "fossil" often conveys to our minds another idea: the remains of plants and animals belonging to the primaeval world are called fossils, in contradistinction to those of the present world, so that the bones of species of animals now existing, as, e.g., the present races of dogs, sheep, and cattle, would not be called fossils, even if they were found petrified or buried in strata.2 This strict distinction between the primaeval and the present world is connected with the theory that the plants and animals which are supposed to belong to the earlier periods of the earth's history all

formed of the smaller shell animals, which are called foraminifera or polythalamaceae; millions of their bodies were required in order to form one cubic foot of chalk. (Vogt, Lehrb. der Geol. i. 560.) In the limestone which is used for building in Paris, there are such enormous masses of foraminifera of the size of a grain of millet, that we may say that Paris is, in great part, built of these Crustacea. (Wagner, Gesch. der Urwelt, ii. 510. Cf. Lyell, Geology, i. 35.)

1 Leonhard, Geologie, iii. p. 520. Fraas, p. 448.

a Fraas, p. 450. Marcel de Serres suggests that the name "Humatiliae" be used instead of fossils for petrifactions of this latter kind.

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