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The list of Caithness shells combines Mr. Peach's two lists (for which see 'Brit. Assoc. Report' for 1862, Trans. of the Sections, p. 83, ibid. for 1864, p. 61), and also some additional species enumerated in a paper lately communicated by him to the Physical Society of Edinburgh.

For the Fort William list see Jeffreys in the Brit. Assoc. Report' for 1862, Trans. of the Sections, p. 73. For that from Elie see the Rev. Thomas Brown in the 'Proceedings of the Royal Society of Edinburgh' for March 2nd, 1863. The others will be found in the Appendix to my paper in the Quart. Journ. Geol. Soc.' vol. xxi. p. 161, 1865.

In the two following Tables

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Southern means species living on the west coast of Europe, to the south of lat. 50°.

British means species living on the coasts of Britain.

Northern means species living on the west coast of Europe, south of lat. 60° and the Arctic circle.

Arctic means species living within the Arctic circle.

N. E. American means species living on the east coast of North America.

TABLE I.—List of Mollusca whose Shells are found in the Glacial Drift of Caithness.

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Norvegicum

14 Cerithiopsis costulata=Turritella? costulata, Möller.

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Of the above shells the Turritella and Cyprina are probably the most common. Astarte, Natica, Tellina, Saxicava, and Mya are also pretty frequent, and so likewise are Dentalium entalis, Leda pernula, Cardium echinatum, and Mangelia turricula. The scale of frequency, however, differs in different localities. Some of the species have been determined from single fragments, as, for example, Venus ovata and Trochus zizyphinus.

Patella vulgata is a shell I have never myself found in any of our Scotch glacial beds, but Mr. Peach informs me he got one pretty perfect specimen, besides two or three fragments. Mr. Dick also told me he had found it. In regard to some of the other species Mr. Peach has supplied me with the following information :-" Pecten maximus and opercularis, in fragments, occur frequently. Cardium Norvegicum, two or three hinge-pieces. Fusus antiquus, two pillarlips. Ostrea edulis, one pretty large shell and several fragments"; and he says there can be no doubt whatever that these occur in the very same deposits as the more Arctic forms.

TABLE II.—Showing the Geographical relations of groups of Mollusca whose Shells occur in some of the Scottish Glacial beds.

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Some interesting information may be gathered from the foregoing Table.

The Errol and Elie groups, it will be seen, are intensely Arctic; the shells are just such as we might find in the sea of Spitzbergen at the present day, many of the species not ranging south of the Arctic circle. In them the proportion of British species is less than 50 per cent., while that of the Southern has dwindled down to a very small fraction. These two groups I take to represent an early stage of the glacial-marine beds when the rigour of the climate was at its height.

The groups from King-Edward, Paisley, Kilchattan, and Gamrie probably belong to a somewhat later stage, for although the general character is still Arctic, yet it is less strictly so than in the two preceding. The proportion of Southern forms is far greater, and the British exceed 50 per cent.

The Fort William group is probably the latest of all; it is no longer Arctic but Northern, and the British species exceed 80 per

cent.

The Caithness group seems to be a mixture of species from glacial beds of both earlier and later date.

The high percentage of North American forms in all the groups, but more especially in the first six, is a feature of much interest.

February 21, 1866.

William Henry Corfield, Esq., B.A., Fellow of Pembroke College, Oxford, University College Hospital, Gower Street, W.C.; Henry Lee, Esq., The Waldrons, Croydon; Henry Skiffington Poole, Esq., B.A., Cape Breton, Nova Scotia; Alexander Ramsay, jun., Esq., 45 Norland Square, Notting Hill, W.; Charles Pearce Serscold, Esq., Taplow Hill, and 24 Oxford Square; George Suche, Esq., 77 Grosvenor Street, W.; and James Maurice Wilson, Esq., M.A., Fellow of St. John's College, Cambridge, Rugby School, were elected Fellows.

The following communications were read:

1. On the TERTIARY MOLLUSCA of JAMAICA.

By R. J. LECHMERE GUPPY, Esq., Civil Service, Trinidad.
(Communicated by Henry Woodward, Esq., F.G.S., F.Z.S.)
[PLATES XVI-XVIII.]

§ 1. THE RELATIONSHIPS OF THE MIOCENE OF JAMAICA. IN 1862 Mr. Lucas Barrett, Director of the Geological Survey of the West Indies, brought over from Jamaica and deposited in the British Museum a collection of Miocene fossils. In 1863 Mr. Carrick Moore communicated to the Geological Society the results of his examination of the shells, Dr. Duncan described the corals, and Prof. Rupert Jones gave an account of the Foraminifera *. In 1864 Dr. Duncan and Mr. Wall gave a sketch of the geology of a part of Jamaica, showing the relations of the Cretaceous and Tertiary formations exposed in that island +. In the same communication Dr. Duncan described several new and interesting corals from the Cretaceous, Eocene, and Miocene strata; but beyond the general results given in Mr. Carrick Moore's paper above referred to, the shells have remained untouched. It was, I believe, the intention of Mr. Barrett to have worked out this portion of the subject, and, indeed, he had already had one plate engraved, which has since been destroyed for want of instructions; but as his untimely and lamented death has intervened to prevent our receiving the benefit of his illustration of the fossils alluded to, I have undertaken to furnish an account of these remains ‡. * Quart. Journ. Geol. Soc., vol xix. p. 510.

+ Ibid., vol. xxi. p. 1.

The following extract from a letter of Mr. Barrett was published by Dr. Woodward in an obituary notice of that naturalist: "The Tertiary system of

VOL. XXII.-PART I.

X

In the paper by Dr. Duncan and Mr. Wall, before cited, the relations of the various strata are so well and succinctly described, that it is unnecessary for me to do more in this place than to allude to the fact that the formation whence the mollusca to be described were derived consists of shales, sands, and marls exposed in several parts of Jamaica, and that it has suffered great disturbance, in common with the Tertiary strata of other parts of the West Indies, and is frequently found in a position approaching to the vertical. The identity of many of the species found in these rocks with forms from San Domingo, Cuba, Cumana, Antigua, Anguilla, and Trinidad, shows the very extended development of Miocene formations in the Caribean The period appears to have been one of exuberant development of marine life, and the conditions seem on the whole to have been favourable to the preservation of the shells and other remains.

area.

The general remarks made by Mr. Carrick Moore in his papers on the San Domingan Tertiary fossils are as a rule applicable to those of Jamaica; and many of those observations have been confirmed by Dr. Duncan's investigations of the corals, and those of Prof. Rupert Jones of the Rhizopoda. Among the new facts brought to light is the very remarkable resemblance of a portion of the West Indian Miocene fauna to that of the Maltese beds.

The great difference between the Miocene faunas of the American and Caribean areas is particularly remarkable when we take into consideration the alliances of the latter with the European Mid-tertiaries, and the more we investigate the subject, the more we find to confirm the conclusions already arrived at on this head. Still, there is a certain amount of resemblance, and, upon examination, I find that the Petaloconchus Domingensis of Sowerby, appears identical with P. sculpturatus of Lea, from the Miocene of Virginia.

From my examination of the Jamaican fossils, I am of opinion that, with the Middle Tertiary beds of San Domingo and Cuba, those of Cumana, and the Caroni series in Trinidad, the Miocene of Jamaica is to be considered as representing the upper or later part of the West Indian Miocene as at present known; while the Chert-formation in Antigua, the Anguilla beds, and the beds exposed at San Fernando in Trinidad, belong to the lower and older part of the Miocene.

In Jamaica the Miocene strata consist of highly inclined marls and shales, which are especially characterized by Conus, Strombi, and large Pleurotoma, with small Nummuline and Orbitoides, as well as corals. At Cumana we have a fauna almost identical with that of Jamaica, including similar foraminifera and corals; among the latter is Flabellum exaratum, Dunc. The beds consist in part of

Jamaica is very interesting, though I have not been able to separate it into Sir Charles Lyell's divisions. I must first study the recent shells of Jamaica. The newer Tertiary strata contain a Terebratula (with a short loop) a Terebratulina (like caput-serpentis) and an Argiope. There is a marl-bed, probably formed in the deep sea, containing abundance of Pteropods (Cleodora, "Creseis, Cuvieria).” -Critic,' February 1, 1863.

* Quart. Journ. Geol. Soc. vol. vi. p. 39, and vol. ix. p. 129.

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