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would be much more applicable to the Rhynchosaurus; for although a more striking approach to the class of birds is made by the pectoral extremity, which endowed the Pterodactyle with the power of flight, it is, the professor observes, precisely in the structure of the cranium that it adheres most closely to the Saurian type of structure.
Dr. Buckland accounts for the discordance of opinion above noticed, respecting the nature of a creature whose fossil skeleton was almost entire, by alluding to the presence of characters in it, apparently belonging to each of the three classes to which it was referred. There were the birdlike neck and head, the wing approaching in form and proportion to that of the bat, and a body and tail approximating to that of the mammal.
"These characters," says Dr. Buckland, "connected with the small skull, as is usual among reptiles, and a beak furnished with not less than sixty pointed teeth, presented a combination of apparent anomalies which it was reserved for the genius of Cuvier to reconcile. In his hands, this apparently monstrous production of the ancient world, has been converted into one of the most beautiful examples ever afforded by comparative anatomy of the harmony that pervades all nature in the adaptation of the same parts of the animal frame, to infinitely varied conditions of existence."*
Although the cervical vertebræ of the Pterodactyles were lengthened in form, their number falls short of that of birds. Not more than six or seven have been found in the extinct flying Saurians, whilst they are numerous in the plumed bipeds; the neck of the swan consists of no less than twenty-three. The thin slender lizardlike ribs of the Pterodactyle form a strong contrast to the flat and broad costal apparatus of birds; and in the pelvic bones of the extinct Saurian, the lacertian type is followed. The metatarsal bones of the foot are distinct in the Pterodactyle, but consolidated in the bird.
It is in the bones of the forefoot, however, that the modification of the reptile, for the medium in which it was sustained, is most striking. There is no difference in the number, and but little in proportion between the bones of a living lizard's forefoot, and those of a Pterodactyle's anterior or pectoral extremity; but the latter are so arranged as to fit them for expanding the membranous wing which was to enable that strange-looking dragon to steer its flight through the heavy atmosphere,
Aloft, incumbent on the dusky air,
an operation which its low organization, and comparatively weak
muscular irritability, would have rendered far more difficult in the rarer and purer fluid that now surrounds our earth. This wing differed much in the arrangement of its bones from that of the bat.
The eye of the Pterodactyl was very large, and the animal was probably noctivagous as well as diurnal.
Of these anomalous creatures no less than seven species have been described and named; nor is there reason for doubting that more remain to be discovered: an eighth undescribed species has been found at Stonesfield. Two of these are British, both brought to notice by Dr. Buckland; and the most perfect of these, the head of which, however, is wanting, is the Pterodactylus macronyx, Buckl., from Lyme Regis in Dorsetshire.
Dr. Buckland is of opinion that these Pterodactyles did not suspend themselves, when at rest, with their heads downward, like the bats; but he relies on the size and form of the thigh, leg, and foot, for the inference that they had the power of standing firmly on the ground, (where they possibly moved with folded wings, after the manner of birds,) and of perching on trees, and climbing on rocks and cliffs, by the joint aid of their anterior and posterior extremities, like bats and lizards.
With submission to an authority worthy of the greatest respect, we cannot subscribe to the whole of this inference. The smallness and weakness of the pelvis forbids us to agree with Dr. Buckland, when he infers that the Pterodactyle stood firmly on the ground, and probably moved thereon with folded wings, after the fashion of a bird. The hooks on the anterior extremities would not only have enabled this Saurian to suspend itself when it wished to rest, but to drag itself along prone on the earth, on which the structure of the pelvic organization forbad it to walk like a bird.
A careful examination of the whole osseous fabric conducts us to the conclusion that the Pterodactyle shuffled along upon the ground, after the manner of a bat, and scuttled through the water when it had occasion to swim; nor do we see why it might not, when at rest, have suspended itself by the hind-legs, like the volatile quadruped. The general hue of the body was probably lurid, and the texture of the skin shagreen-like, resembling in some degree the external tegument of a chameleon or guana, excepting the smooth membrane of the wing.
Insects, such as the large fossil dragon-flies (Libellulæ), disinterred with them from the Solenhofen quarries, and Coleoptera, whose elytra are found with the bones of the Stonesfield species in the oolitic slate there, contributed, doubtless, to their food,
but Dr. Buckland well observes that the head and teeth of some species are so much larger and stronger than would be required for insect capture, that the greater Pterodactyles may possibly have fed on fishes, darting upon them from the air, after the manner of Terns or Solan geese. The enormous size and strength of the head and teeth of Pterodactylus crassirostris, he adds, would not only have enabled it to catch fish, but also to kill and devour the few small marsupial animals which then existed upon land.
Such were the heteroclite animals to which nothing modern can in the slightest approach be comparable, except perhaps the pictorial dragons of a Chinese screen, and such in all probability were their habits when thousands of years ago they flitted heavily above
"The pois'nous fields with rank luxuriance crown'd,”
where the wholesome air now refreshes the well-cultivated land white to harvest, and the healthy civilized race of men, whose holy and happy day of rest is announced by the sabbath bell.
If the ploughshare, brightened by the fertile soil which it now divides, brings before us, when it turns up from the furrow some ancient Italian coin, the march of the Roman legions over our hills, plains, and valleys, what visions does the petrified bone of one of these Preadamite Saurians call forth!
Look at the reptilian relic in the stone which helps to form that cottage wall. As we gaze, the wall disappears; and, to the mind's eye, its place is occupied by a vast sea, which, when circulation animated that bone, covered its site. Through the waters of this sea, Ichthyosaurs, Plesiosaurs, Mosasaurs, and Cetiosaurs dart, swim, and gambol. If we turn landward, the sluggish river, the marshy jungle and the dreary plain seem peopled by ancient Crocodilians, Iguanodons and Megalosaurs, while Pterodactyles appear to hover in the murky atmosphere of the old dragon times.
Now, how changed the scene! Instead of animals of a low grade of organization, which then were the highest and predominant forms, the most elaborate and perfect of the animated works of the Creator abound.
Pterodactyles have been succeeded by birds-Ichthyosaurs, Plesiosaurs, Mosasaurs, and the like, by whales, dolphins, and great fishes. Where the herbivorous Iguanodon revelled, the ox, the deer, and the sheep, quietly crop the fragrant herbage; whilst in place of the destructive Megalosaur, the carnivorous mammalia keep down the excessive multiplication of the ruminants;
and MAN has the dominion over all. In future ages his remains will fill the bosom of the earth; and the traveller in some far distant century will feel the full force of Byron's lines wherever he sets his foot: