Geology and Inhabitants of the Ancient World

by Richard Owen

As the thigh-bone (femur) and leg-bone (tibia) measure each nearly three feet, the entire hind-leg, allowing for the cartilages of the joints, must have attained a length of two yards: a bone of the foot (metatarsal) thirteen inches long, indicates that part, with the toes and claws entire, to have been at least three feet in length. The form of the teeth shows the Megalosaurus to have been strictly carnivorous, and viewed as instruments for providing food for so enormous a reptile, the teeth were fearfully fitted to the destructive office for which they were designed. They have compressed conical sharp-pointed crowns, with cutting and finely serrated anterior and posterior edges; they appear straight, as seen when they had just protruded from the socket, but become bent slightly backwards in the progress of growth, and the fore part of the crown, below the summit, becomes thick and convex.

A minute and interesting description of these teeth will be found in Dr. Buckland’s admirable “Bridgewater Treatise” (vol. i. p. 238), from which he concludes that the teeth of the Megalosaurus present “a combination of contrivances analogous to those which human ingenuity has adopted in the construction of the knife, the sabre, and the saw.” The fossils which brought to light the former existence of this most formidable reptile, were discovered in 1823, in the oolitic slate of Stonesfield, near Oxford, and were described by Dr. Buckland, in the volume of the “Geological Transactions” for the year 1824.

Remains of the Megalosaurus have since been discovered in the “Bath oolite,” which is immediately below the Stonesfield slate, and in the “Cornbrash,” which lies above it. Vertebræ, teeth, and some bones of the extremities have been discovered in the Wealden of Tilgate Forest, Kent, and in the ferruginous sand, of the same age, near Cuckfield, in Sussex. Remains of the Megalosaurus also occur in the Purbeck limestone at Swanage Bay, and in the oolite in the neighbourhood of Malton, in Yorkshire.

Mr. Waterhouse Hawkins’s restoration, according to the proportions calculated from the largest portions of fossil bones of the Megalosaurus hitherto obtained, yields a total length of the animal, from the muzzle to the end of the tail, of thirty-seven feet; the length of the head being five feet, the length of the tail fifteen feet; and the greatest girth of the body twenty-two feet six inches.

Nos. 8 & 9.—Pterodactyles of the Oolite.

To the right of the Hylæosaurus, on the rock representing the greater oolite formation, are restorations of species of Pterodactyle (Pterodactylus Bucklandi, No. 9), smaller than and distinct from those of the chalk formations. The remains of Buckland’s Pterodactyle are found pretty abundantly in the oolitic slate of Stonesfield, near Oxford.

Nos. 10 & 11.—Teleosaurus.

On the shore beneath the overhanging cliff of oolitic rock are two restorations, Nos. 10 and 11, of a large extinct kind of crocodile, to which the long and slender-jawed crocodile of the Ganges, called “Gaviàl” or “Gharriàl” by the Hindoos, offers the nearest resemblance at the present day. Remains of the ancient extinct British gavials have been found in most of the localities where the oolitic formations occur, and very abundantly in the lias cliffs near Whitby, in Yorkshire. The name Teleosaurus (telos, the end, sauros, a lizard), was compounded from the Greek by Professor Geoffroy St. Hilaire, for a species of these fossil gavials, found by him in the oolite stone at Caen, in Normandy, and has reference to his belief that they formed one—the earliest—extreme of the crocodilian series, as this series has been successively developed in the course of time on our planet.

The jaws are armed with numerous long, slender, sharp-pointed, slightly curved teeth, indicating that they preyed on fishes, and the young or weaker individuals of co-existing reptiles. The nostril is situated more at the end of the upper jaw than in the modern gavial: the fore-limbs are shorter, and the hind ones longer and stronger than in the gavial, which indicates that the Teleosaur was a better swimmer; the vertebræ or bones of the back are united by slightly concave surfaces, not interlocked by cup and ball joints as in the modern crocodiles, whence it would seem that the Teleosaur lived more habitually in the water, and less seldom moved on dry land; and, as its fossil remains have been hitherto found only in the sedimentary deposits from the sea, it may be inferred that it was more strictly marine than the crocodile of the Ganges.

The first specimen of a Teleosaur that was brought to light was from the “alum-schale” which forms one layer of the lofty lias cliffs of the Yorkshire coast, near Whitby. A brief description, and figures, of this incomplete fossil skeleton were published by Messrs. Wooller and Chapman, in separate communications, in the 50th volume of the “Philosophical Transactions,” in 1758. Captain Chapman observes, “it seems to have been an alligator;” and Mr. Wooller thought “it resembled in every respect the Gangetic gavial.” Thus, nearly a century ago, the true nature of the fossil was almost rightly understood, and various were the theories then broached to account for the occurrence of a supposed Gangetic reptile in a petrified state in the cliffs of Yorkshire. It has required the subsequent progress of comparative anatomy to determine, as by the characters above defined, the essential distinction of the Teleosaur from all known existing forms of crocodilian reptiles.