EXTRANEOUS FOSSILS.
The fossil remains of animals not now in existence, entombed and preserved in solid rocks, present us with durable monuments of the great changes which our planet has undergone in former ages. We are led to a period when the waters of the primitive ocean must have covered the summits of our highest mountains, and are irresistibly compelled to admit one of two conclusions: either that the sea has retired, and sunk beneath its former level; or that some power, operating from beneath, has lifted up the islands and continents, with all their hills and mountains, from the watery abyss to their present elevation above its surface.
The calcareous, or limestone mountains in Derbyshire, and at Craven, in Yorkshire, having an elevation of about two thousand feet above the present level of the sea, contain, in a greater or less abundance, and throughout their whole extent, fossil remains of zoophytes, shell-fish, and marine animals. No remains of vegetables have been found in the calcareous mountains of England; but, in the thick beds of shale and gritstone lying upon them, are found various vegetable impressions, and above these regular beds of coal, with strata, containing shells of fresh-water mussels[mussels]. In the earthy limestone of the upper strata are sometimes found fossil flat-fish, with the impression of the scales and bones quite distinct. The mountains of the Pyrenees are covered in the highest part, at Mont Perdu, with calcareous rocks, containing impressions of marine animals; and, even where the impressions are not visible in the limestone, it yields a fetid cadaverous odor, when dissolved in acids, owing, in all probability, to the animal matters it contains. Mont Perdu, which rises ten thousand five hundred feet, or about two miles above the level of the sea, is the highest situation in which any marine remains have been found in Europe. In the Andes they have been observed by Humboldt at the hight of fourteen thousand feet, more than two miles and a half. Lastly, in southern countries, in and under beds of clay-covering chalk, the bones of the elephant, and of the rhinoceros are frequently found.
These bones, as they have been brought from different parts of the world, have been examined with the utmost attention by the sagacious naturalist Cuvier. He has observed characteristic variations of structure, which prove that they belong to animals not now existing on our globe: nor have many of the various zoöphytes and shell-fish, found in calcareous rocks, been discovered in our present seas. From these very curious facts he makes the following deductions.
“These bones are buried, almost everywhere, in nearly similar beds: they are often blended with some other animals resembling those of the present day. The beds are generally loose, either sandy or marly; and always neighboring, more or less, to the surface. It is, then, probable that these bones have been enveloped by the last, or by one of the last, catastrophes of this globe. In a great number of places they are accompanied by the accumulated remains of marine animals; but in some places, which are less numerous, there are none of these remains: sometimes the sand or marl, which covers them, contains only fresh-water shells. No well authenticated account proves that they have been covered by regular beds of stone, filled with sea-shells; and, consequently, that the sea has remained on them undisturbed, for a long period. The catastrophe which covered them was, therefore, a great, but transient, inundation of the sea. This inundation did not rise above the high mountains; for we find no analogous deposits covering the bones, nor are the bones themselves there met with, not even in the high valleys, unless in some of the warmer parts of America. These bones are neither rolled nor joined in a skeleton, but scattered, and in part fractured. They have not, then, been brought from afar by inundation, but found by it in places where it has covered them, as might be expected, if the animals to which they belonged had dwelt in these places, and had there successively died. Before this catastrophe, these animals lived, therefore, in the climates in which we now dig up their bones: it was this catastrophe which destroyed them there; and, as we no longer find them, it is evident that it has annihilated those species. The northern parts of the globe, therefore, nourished formerly, species belonging to the genus elephant, hippopotamus, rhinoceros, and tapir, as well as to that of the mastodon; genera of which the four first have no longer any species existing, except in the torrid zone; and the last, none in any part.”
The researches of Dr. Buckland, connected with the kind of relics of which we are speaking, have given them additional interest, especially as connected with certain points of diluvial geology, and with their assemblage in caverns. In these caverns, the bones are usually found mixed with mud, stones and fragments; and circumstances seem to show that the animals resided in them for a great length of time. The celebrated Kirkdale cavern, in Yorkshire, discovered in 1821, contains the remains of the hyena, tiger, bear, wolf, fox, weasel, elephant, rhinoceros, hippopotamus, horse, ox, deer, hare, rabbit, rat, mouse, raven, pigeon, lark, thrush, and a species of duck. From the mode in which these remains were strewed over the bottom of the cavern, from the great proportion of hyenas’ teeth over those of other animals, and from the manner in which many of the bones were gnawed and fractured, Dr. Buckland infers that this cavern was the den of hyenas for a long succession of years; that they brought in as their prey, the animals whose remains are thus mixed with their own; and that this state of things was suddenly terminated by an irruption of turbid water into the cave, which buried the whole in the mud in which they are now intermingled. In other cases, the bones of other animals have been found, indicating the same general facts as to the existence of animals now no longer known in the same latitudes.
That every part of the dry land was once covered by the ocean, is a fact on which all geologists agree; and the discovery, noticed above, of the fossil remains of many genera of quadrupeds, once existing, but which have now disappeared from the earth, leads to another fact, not less interesting, and which is at the same time coincident with the oldest records or traditions of the human race, namely, that at the period when these great changes took place, man was not an inhabitant of the planet. These fossil remains, now about to be particularized, are among the most surprising of nature’s phenomena, and irresistibly lead to most interesting speculations respecting the past and future condition of the terrestrial globe.