While, therefore, all agree in considering the mammalian remains generally to be extraneous fossils, there is a difference of opinion, but not a great one, with respect to their age and origin. Some small portion of these fossils are doubtless of the age of the Red Crag. Unlike the great proportion of the Mammalian and Cetacean remains, which possess so peculiar a fossilization, are so dense and so worn that they show at once their extraneous origin, some of the large Whale-vertebrae and some of the small fish-vertebra? are so little mineralized and worn that they cannot be considered derived fossils*. At the same time the very circumstance that a portion of the Cetacean remains are, like the land Mammalian remains, heavily mineralized and worn, makes one cautious how far that mineralization and that wear should be construed as a proof of extraneous origin.
The discovery by Mr. Colchester (ante, p. 117), in the pit which he opened at Sutton, of teeth of Mastodon, Rhinoceros, &c, with Cetacean remains, all of the same species as those found in the Red Crag, and, like the latter, in a shingle-bed at the very base of the Coralline Crag, shows that some of these remains of the Red Crag may have been derived directly from the Coralline Crag, although they may have to be carried yet further back in the geological series†; while I consider it probable that some will be found to be of the age of the Coralline Crag itself.
Mr. Darwin describes‡ eight species of Cirripedia from the Red Crag, of which six are living and two supposed to be extinct.
Edward Forbes § described six species of Echinoderms, one of which only he identified with a living species ; but one is probably derived from the Coralline Crag ; Echinocyamus suffolcensis is probably only a variety of the E. pusillus ; and Echinus Henslowii he thought might be related to an undescribed species from Iceland. This would give one extinct to three living species.
Land.
Tapirus priscus, Kaup.
Ursus arvernensis, Cr. & Job.
Megaceros hibernicus ?
To these I would add
Elephas (meridionalis ?).
Marine.
Lamna.
Otodus.
Phocaena.
Squalodon (antverpiensis?).
Trichecodon Huxleyi, Lank.
Ziphius angulatus, Ow.
— angustatus, Ow.
— compressus, Ow.
— gibbus, Ow.
— medilineatus, Ow.
— planus, Ow.
— tenuirostris, Ow.
- The finest series of the extraneous fossils of Red Crag I know of is that forming part of the valuable collection of Red-Crag fossils in the possession of Mr.
Whincopp, of Woodbridge, who has devoted much time and care to secure the many rare specimens brought to light by the Coprolite-diggings which for the last few years have been carried on so actively in the neighbourhood of Sutton and Woodbridge.
† In the same way it is probable that the dark sandstone nodules, with casts and impressions of shells, so common in the Red Crag at Bawdsey, Sutton, &c., may have been derived indirectly through the Coralline Crag.
‡ Pal. Soc. 1854.
§ Ibid. 1852.
