Omphalos: An Attempt to Untie the Geological Knot

by Philip Henry Gosse

In the first place, the great size of the tooth indicates maturity; and is in keeping with the dimensions of the animal,—some twenty feet or so,—which are those of an adult, if not a full-grown individual. But adult age implies previous youth and infancy, and a gradual growth from the length of a few inches to this formidable size. The teeth are found in the embryo Shark when not more than a foot long; and it is evident that many successive generations of teeth have passed away between those pristine lancets of a line in diameter, and these of an inch and a half.

But stay; there is a peculiarity in the structure of these present teeth, which surely indicates their place to be far on in the succession. Each is seen to be finely serrated on its two outer edges,—a provision which, of course, makes them more effective dividers of flesh and bone. But this structure is not found in the teeth of young individuals, which up to a period comparatively advanced, have simply cutting edges.

Hence we are compelled by the phenomena to infer a long past existence to this animal, which yet has been called into being within an hour.

On yonder twig sits a beautiful little Tree-frog, which you would be ready to mistake for a leaf of more than usually emerald hue, but for the glittering eye, and the line of yellow edged with purple that passes down the side. Do you notice the frequent gulpings of the throat? Those are the periodic inspirations Of air, by which the creature breathes; for, having no ribs, by means of which to depress, and so to expand, the thoracic cavity, the Frog swallows the air by a voluntary action. These air-gulps afford us another example of the sort of evidence we are searching for; they are so many proofs of a past history. For the Tree-frog has not always swallowed air; there was a period in its life when it had no lungs; when it was an aquatic animal, as exclusively a water-breather as any fish. Fish-like in form it was then, as well as in habit; it was a tadpole with a long compressed muscular tail, and with external gills of several branches, but as destitute of lungs as it was of limbs. Any physiologist, looking at our little green Tree-frog, would pronounce without hesitation on the stages through which it has passed; and would describe with the most perfect confidence the order in which they took place; the gradual absorption of the branchiæ, the development of the lungs, the shrinking up and final disappearance of the tail, the budding forth of the tiny rudimentary limbs, the hinder pair first, then the fore pair, and the subsequent division of their extremities into toes;—the metamorphosis of the little fish into a little batrachian, and the gradual growth and maturation of the latter,—these are facts,—the physiologist would say,—as sure both as to their actuality and as to their order, as that the Frog is a Frog.

Ah! but the physiologist is not aware of a fact, which invalidates all his conclusions based upon experience,—the fact that the little Tree-frog has been created but this very instant.

Hark! that rattling noise is an admonition to us to tread circumspectly. It is the vibration of the horny caudal appendages of a Rattlesnake. And I see the reptile coiled up under yonder shadowing leaf. But our presence is a privileged presence, and so we may handle and examine him with impunity. The organ which produces this sound is composed of a number of hollow horny capsules, each one fitting into the next, in which it is retained loosely by a protuberance of its surface. These, being agitated at the will of the animal, produce that sound which we just now heard. The capsules are developed periodically, one being added to the number already existing every year, until as many as forty are accumulated.[82] This individual, therefore, having five-and-twenty rattles, must be five-and-twenty years old.

This Snake, however, has had no past years; it has had no yesterday. Its existence commenced this hour.

Here crouches, among the thick reeds, the Leviathan of the rivers, the mailed Crocodile. His body, invested with bony ridged plates, that rise into strong serrations along the tail, seems clothed with power; and his long rows of interlocking teeth, unveiled by lips, appear grinning with perpetual rage. An experienced herpetologist would not fail to find many evidences of age in this huge reptile. First of all, he would point to its monstrous size; then to the breadth and massive thickness of the dermal plates. "The head," he would say, "in the ruggedness of its surface, shows the same thing, for in youth it was comparatively smooth; and also in the form of its outline; for in this example its length is double its breadth, whereas in youth, these measurements were nearly equal. These conical teeth, too, are by no means the same individual teeth which existed at first. If you look at the base of one, you will see that it is hollow, and that the sides of this portion are already in process of absorption; that this hollow cone is a sheath for another tooth beneath, which is destined to replace it; as this has itself replaced its predecessor. The large size of the teeth which we see, therefore, which accords with the dimensions of the jaws, is not a condition induced by gradual growth, but by a succession of sloughings and replacements; and hence the present teeth, in their size, point conclusively to others which have preceded them, but which have disappeared."

Yet nothing can be more certain, than that, in this Crocodile, which has been created to-day, the successive teeth thus witnessed to, are but ideal, that is prochronic, teeth; and that all the other indications of the lapse of time, in the development of this individual, are liable to the same exception.

See this solemn, slow-going Tortoise, shut up in his high-domed house of bones. It is the beautiful Testudo pardalis, well named from the plates being elegantly spotted and splashed with black on a pale-yellow ground, like the fur of the panther. This is a rather large individual, and the number of concentric lines on the plates of his armour,—or may I not rather say the tiles wherewith his house is roofed?—is commensurately great. You see what I mean. Each of the angular plates has a small nuclear lamina, not in the centre of the area, for the development has been one-sided, but on the highest part. This was the plate in its earliest form, or at least the earliest of which any trace is left; for probably there were others yet earlier and smaller, which, on account of their thinness, have been rubbed away in the travels of the old wanderer. From this nucleus, the plate has been successively enlarged, to correspond with the general growth of the animal, by repeated additions of new laminæ to the inferior surface; each new lamina being a little wider in every direction than that which preceded it, though not equally on all the margins; and thus the plates assumed the form of a very low cone, as you see, always preserving the specific outline, and manifesting the stages of increase, by the projecting edges of the successive laminæ, exactly as we saw lately in the scales of the fish.