Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/246

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132
PROCEEDINGS OF THE GEOLOGICAL SOCIETY.

other parts of the Lowest or White Crag of Suffolk, as far as our collections serve, we have got a somewhat similar fauna, not only greatly reduced in number of individuals and variety of form, but composed of dwarfs in contrast with those of Sutton, except in the case of some of those that inhabit shallow water, as Rotalia Beccarii and Polystomella crispa, and even these are but feeble. Hence we may suppose that the Foraminiferal deposit at Sutton was formed either in deeper or in warmer water than other portions of the Crag were. Some of our sources of these less luxuriant growths are specimens of Crag full of Cyprina and Cardita; and as the former shells live in the British seas at from 5 to 80 fathoms, a depth similar to that affected by the Atlantic and Mediterranean groups of Foraminifera above alluded to, we must suppose that some deteriorating influence, either cold currents, floating ice, or cold climate, was at work locally, at least, in the Crag, excepting possibly the Sutton area."

Fish-remains.—A sea like that of the Coralline Crag doubtless contained its due proportion of fishes. Their remains nevertheless are scarce. This can in part be accounted for by the fact that a proportion of them were probably cartilaginous fishes. Small vertebrae of fishes and otoliths are not so scarce. The subject, however, has received little attention, and requires further investigation. Mr. Higgins states that all the Crag otoliths which have passed through his hands belong to Gadoid fishes. The species which he has been able to recognize are:—

(Morrhua.) Common Cod.
probably identical.
(Morrhua.) Green Cod.
(Morrhua.) Power Cod.
(Merlangus.) Pollack.
nearly allied, but not identical.
(Merlangus.) Whiting.
(Merlangus.) Whiting-pout.

Large teeth of the extraneous Carcharodon megalodon with those of Otodus, and remains of Platax Woodwardi, of Raia antiqua, and Zygobatis Woodwardi are common in this as they are in the Red Crag.

Mammalian Remains.—The term "Mammaliferous Crag" was especially applied to the Norwich Crag by Mr. Charlesworth, to indicate the common occurrence of mammalian remains in that Crag, in contradistinction to their scarcity in the Crags of Suffolk. The extensive workings of the Red Crag have since shown that it also is rich in such remains; but they present this difference from the fossils of the Norwich Crag, that whilst the latter are in greater part or in whole those of animals living at the time of the Norwich Crag, those found in the Red Crag are, on the contrary, in great part, if not altogether, those of animals which lived at previous times and are derived from older strata. Of this we shall have to speak more fully when on the subject of the Red Crag. Whilst, however, these two Crags were known to contain mammalian remains, no land Mammalia were known in the Coralline Crag. A few remains of Cetaceans