The Tilgate beds of the Wealden series, just mentioned, have yielded numerous fragments of the most remarkable reptilian fossils yet discovered, and whose wonderful forms denote them to have thronged the shallow seas and bays and lagoons of the period. In the grounds of the Crystal Palace at Sydenham the reader will find restorations of these animals sufficiently perfect to illustrate this reptilian epoch. They include the iguanodon, an herbivorous lizard exceeding in size the largest elephant, and accompanied by the equally gigantic and carnivorous megalosaurus (great saurian), and by the two yet more curious reptiles, the pylæosaurus (forest, or weald, saurian) and the pterodactyl (from pteron, ‘wing,’ and dactylus, ‘a finger’), an enormous bat-like creature, now running upon the ground like a bird; its elevated body and long neck not covered with feathers, but with skin, naked, or resplendent with glittering scales; its head like that of a lizard or crocodile, and of a size almost preposterous compared with that of the body, with its long fore extremities stretched out, and connected by a membrane with the body and hind legs.
Suddenly this mailed creature rose in the air, and realised or even surpassed in strangeness the flying dragon of fable: its fore-arms and its elongated wing-finger furnished with claws; hand and fingers extended, and the interspace filled up by a tough membrane; and its head and neck stretched out like that of the heron in its flight. When stationary, its wings were probably folded back like those of a bird; though perhaps, by the claws attached to its fingers, it might suspend itself from the branches of trees.
MAMMALIA IN SECONDARY ROCKS.
It was supposed till very lately that few if any Mammalia were to be found below the Tertiary rocks, i. e. those above the chalk; and this supposed fact was very comfortable to those who support the doctrine of “progressive development,” and hold, with the notorious Vestiges of Creation, that a fish by mere length of time became a reptile, a lemur an ape, and finally an ape a man. But here, as in a hundred other cases, facts, when duly investigated, are against their theory. A mammal jaw had been already discovered by Mr. Brodie on the shore at the back of Swanage Point, in Dorsetshire, when Mr. Beckles, F.G.S., traced the vein from which this jaw had been procured, and found it to be a stratum about five inches thick, at the base of the Middle Purbeck beds; and after removing many thousand tons of rock, and laying bare an area of nearly 7000 square feet (the largest cutting ever made for purely scientific purposes), he found reptiles (tortoises and lizards) in hundreds; but the most important discovery was that of the jaws of at least fourteen different species of mammalia. Some of these were herbivorous, some carnivorous, connected with our modern shrews, moles, hedgehogs, &c.; but all of them perfectly developed and highly-organised quadrupeds. Ten years ago, no remains of quadrupeds were believed to exist in the Secondary strata. “Even in 1854,” says Sir Charles Lyell (in a supplement to the fifth edition of his Manual of Elementary Geology), “only six species of mammals from rocks older than the Tertiary were known in the whole world.” We now possess evidence of the existence of fourteen species, belonging to eight or nine genera, from the fresh-water strata of the Middle Purbeck Oolite. It would be rash now to fix a limit in past time to the existence of quadrupeds.—The Rev. C. Kingsley.
FOSSIL HUMAN BONES.
In the paleontological collection in the British Museum is preserved a considerable portion of a human skeleton imbedded in a slab of rock, brought from Guadaloupe, and often referred to in opposition to the statement that hitherto no fossil human hones have been found. The presence of these bones, however, has been explained by the circumstance of a battle and the massacre of a tribe of Galtibis by the Caribs, which took place near the spot in which the bones were found about 130 years ago; for as the bodies of the slain were interred on the seashore, their skeletons may have been subsequently covered by sand-drift, which has since consolidated into limestone.
It will be seen by reference to the Philosophical Transactions, that on the reading of the paper upon this discovery to the Royal Society, in 1814, Sir Joseph Banks, the president, considered the “fossil” to be of very modern formation, and that probably, from the contiguity of a volcano, the temperature of the water may have been raised at some time, and dissolving carbonate of lime readily, may have deposited about the skeleton in a comparatively short period hard and solid stone. Every person may be convinced of the rapidity of the formation and of the hardness of such stone by inspecting the inside of tea-kettles in which hard water is boiled.
Descriptions of petrifactions of human bodies appear to refer to the conversion of bodies into adipocere, and not into stone. All the supposed cases of petrifaction are probably of this nature. The change occurs only when the coffin becomes filled with water. The body, converted into adipocere, floats on the water. The supposed cases of changes of position in the grave, bursting open the coffin-lids, turning over, crossing of limbs, &c., formerly attributed to the coming to life of persons buried who were not dead, is now ascertained to be due to the same cause. The chemical change into adipocere, and the evolution of gases, produce these movements of dead bodies.—Mr. Trail Green.
THE MOST ANCIENT FISHES.
Among the important results of Sir Roderick Murchison’s establishment of the Silurian system is the following: