Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/647

Rh

Mr., with reference to the habits of the Walrus, stated, on the authority of Prof. Torell, that it feeds on the Mya truncata, a mollusk which lies buried in gravelly mud. In order to get this raoHusk, it has to grub up the mud with its tusks, and takes up the mud and pebbles along with the Mya into its mouth.

Mr. said he regretted that all the vertebræ of the Saurian had not been brought for exhibition, as the smallest of the cervical vertebræ would have shown more plainly the great dis- proportion existing between them and the vertebræ of the trunk, and thus have given a better idea of the great length of the neck. He remarked that the bones, when in situ, were very fragmentary, and some had oysters adhering to them, showing that they had been long exposed before fossilization. He stated that pebbles were exceedingly rare in the Gault, and suggested that the reptile may have been stranded, and that the pebbles became entangled in its carcass.

Mr. believed, with the author, that the remains indicated a new species of larger size than any previously found in this country. In the long, tapering neck, the lateral position of the articular head of the limb-bones, and the form and structure of the cervical ribs, he noticed resemblances to the large Kimmeridge Plesiosaurus (P. Manselli) which he brought under the notice of the Society several years ago, and which he thought would fall into Prof. Seeley's subgenus Murænosaurus. With regard to the pebbles, he suggested that the animal may not have swallowed them as an aid to the comminution of food in its stomach, but that they were introduced in the stomachs of fish which it had swallowed. The flesh and, subsequently, the bones of these would be digested and absorbed, whilst the indigestible stones, if the stomach of the Plesiosaurus was like that of Crocodiles, would be unable to pass through the small pyloric opening into the intestine, and must permanently remain in the stomach.

The briefly replied.