This authority pointed out an unusual provision for giving support and power of movement to the large head at the extremity of a rather long neck, namely, the occurrence of fine long tendons running parallel to the neck-vertebræ. This does not occur in any modern lizards, whose necks are short, and require no such aid to support the head. They are a compensation for weakness that would otherwise arise from the elongation of the neck, supporting, as it did, such a large head. The neck-vertebræ in this species are large and strong, and capable of great flexibility forwards and backwards, so that the creature, by bending its neck during flight into the shape of an S, could throw its head back towards the centre of gravity. The restoration of the skeleton seen in the figure is by Professor Owen. It is probable that this Pterodactyl could walk on the ground with its wings folded, and perhaps it was also capable of perching on trees, by clinging on to their branches with its feet and toes. When the flying membrane was stretched out it must, on account of the long tail to which it was also attached, have presented a triangular shape, somewhat like a boy's kite. [Illustration: Fig. 33.--Skeleton of _Scaphognathus crassirostris_. 1/3 natural size.] Another genus, also from the lithographic slate of Bavaria, namely, Scaphognathus crassirostris (so called on account of its large beak and jaws), had a very short tail, and its skeleton looks somewhat clumsy for a creature adapted to fly through the air (Fig. 33). Pterodactylus spectabilis, from the same strata, also possessed a very short tail, but has a more elegant and bird-like skull. This pretty little flying dragon was only about as large as a sparrow (see Fig. 34). Its neck is comparatively short, with but few joints. The long slender beak was probably sheathed in horn, and the skull in several ways approaches that of a bird. Since there are no teeth in the jaws, we may suppose that it devoured dragon-flies or other insects, such as we know were in existence during the period when the lithographic stone of Bavaria was being deposited. Those forms that were provided with teeth probably devoured such fishes as they could catch by swooping down upon the surface of the water. [Illustration: Fig. 34.--Skeleton of _Pterodactylus spectabilis_.] Cuvier thought, from the magnitude of their eyes, that Pterodactyls were of nocturnal habits. "With flocks of such creatures flying in the air, and shoals of no less monstrous Ichthyosauri and Plesiosauri swarming in the ocean, and gigantic crocodiles and tortoises crawling on the shores of the primæval lakes and rivers--air, sea, and land must have been strangely tenanted in these early periods of our infant world."[31] [31] Buckland, _Bridgewater Treatise_.