Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/401

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1869.] TAWNEY TEREBRATTULA DIPHYA IN THE ALPS. 305


vost's and Dana's theory in explanation, viz. that it is due to the greater contraction of the earth's crust beneath the ocean, which causes it to sink, while the land on either side becomes elevated by lateral pressure, and by both processes necessarily drained.

2. On the Formation of the Chesil Bank, Dorset. By H. W. Bristow, Esq., F.R.S., F.G.S., and Wm. Whitaker, Esq., B.A., F.G.S.

[This paper has been withdrawn by the permission of the Council.]

3. On a Raised Beach at Portland Bill, Dorset. By W. Whitaker, Esq., B.A., F.G.S.

[This paper has been withdrawn by the permission of the Council.]

4. On the Occurrence of Terebratula diphya in the Alps of the Canton De Vaud. By E. Tawney, Esq., F.G.S., Assoc. R. Sch. Mines. With a Note by Thomas Davidson, Esq., F.R.S., F.G.S.

In answer to certain statements of Prof. Hebert as to the probability of the non-occurrence of Terebratula diphya in the Jurassic Series (Bulletin Soc. Geol. de France, vol. xxiii. p. 530, 1866), it may be well to put on record the following discovery of this species in strata in the Alps of the Canton de Vaud, which belong indubitably to the Oxfordian series. This is, I believe, the first time that this species has been found in Jurassic beds in the Canton.

In the summer of 1867, when exploring the geology of the valley of the Sarine, near Chateau d'Oex (Canton de Vaud), I came upon this fossil in a block of Oxfordian limestone, among the "eboulis" around the chalets of Paray Charbon: these blocks, which are nearly all Oxfordian, have fallen from the ridge of the Vanil Noir. This range, from Mont Cray to Dent de Branleire, which forms here the boundary between the Cantons de Vaud and Fribourg, is formed by an arch of Bajocian (Inf. Ool.) dark grey limestones and shales, surmounted by the Oxfordian series at the N.E. end (Dent de Branleire, &c.); but the vault rises higher where the chain becomes lower, so that at the S.W. end the Oxfordian is thrown off only at the sides, and is quite cut away from the top, the summit of Moot Cray being Bajocian.

As our locality is about the middle of the range, the Oxfordian is seen at some height in the precipices above the chalet.

The Bajocian, which contains Zoophycos scoparius (Heer) abundantly here, and Amm. Humphriesianus, consists of dark-coloured limestones and shales, and is in strong contrast to the blocks of Oxfordian limestone which lie upon it; the latter here is a limestone of lithographic texture and conchoidal fracture. It could not be mistaken for the Neocomian, being thicker-bedded and full of