Fig. 35.—Skeleton of Rhamphorhynchus phyllurus, with delicate impressions of the flying membranes. (After Marsh.)
In the year 1873 was discovered, in the lithographic stone of Bavaria, at Eichstädt, a very beautiful new form of Pterodactyl. This was the Rhamphorhynchus phyllurus. The specimen is in a remarkable state of preservation; for the bones of the skeleton are nearly all in position, while those of both wings show very perfect impressions of the membranes attached to them. Its long tail supported another small leaf-like membrane, which was evidently used as a rudder in flight (see [Fig. 35]). The discovery of this valuable specimen attracted much attention at the time. It was bought, by telegram, for Professor Marsh, and so secured for the Yale College Museum; but a cast may be seen at South Kensington (Wall-case, No. 1, Gallery IV. on plan).
Any one who looks carefully at the beautiful impressions of the wings of this specimen can see that they must have been produced by a thin smooth membrane, very similar to that of bats. When this elegant little creature was covered up by the fine soft mud that now forms the lithographic stone, its wings were partly folded, so that the membranes were more or less contracted into folds, like an umbrella only partly open. These appear to have been attached all along the arm and to the end of the long finger. They then made a graceful curve backward to the hind foot, and probably were continued beyond the latter so as to join the tail. With its graceful pointed wings and long tail, this little flying saurian must have been a beautiful object, as it slowly mounted upwards from some cliff overlooking the Jurassic seas. (See [Plate XII.])
Like those already described, it was provided with four short-clawed fingers, as well as the one which mainly supported its wing. Some of the Continental museums contain good collections of fossil Pterodactyls; but the largest collection in the world is that of Yale College, where Professor Marsh declares there are the remains of six hundred individuals from the American Cretaceous rocks alone!
Fig. 36.—Skull of Pteranodon. 1. Side view. 2. Top view. (After Marsh.)
Some of the fragmentary remains from our Cambridge Greensand formation indicate Pterodactyls of enormous size. Thus the neck-vertebræ of one species measure two inches in length, while portions of arm-bones are three inches broad. It is probable that the creatures to which these bones once belonged measured eighteen or twenty feet from tip to tip of the wings. Other also fragmentary remains from the chalk of Kent testify to the existence of Pterodactyls during that period fully equal in size.
But the largest Pterodactyls hail, like so many other big things, from America. Professor Marsh tells us of monsters in his famous collection with a spread of wings of twenty to twenty-five feet! These large forms had no teeth in their jaws, and their skulls are of a peculiar form. The long-pointed jaws were probably sheathed in horn during life, as in birds (see [Fig. 36]). According to Marsh, these toothless forms (which he calls Pteranodonts) were mostly of gigantic size. With regard to their food it is almost vain to speculate; but if they did prey upon fishes, they must have had a capacious mouth and gullet, and must have swallowed their prey whole, after the fashion of pelicans. But we doubt if they had the peculiar pouch possessed by those birds. In the absence of more complete accounts of the large forms the artist has only attempted to restore the small ones. (See [Plate XII.], showing four different kinds.)