16 Hart Street, Bloomsbury
Square, London 

My dear Sir,

            I employed myself last summer in examining the Crag of Norfolk and Suffolk, and I am sure that the conclusions at which I have arrived will be interesting to you, as they coincide for the most part with some of your opinions which I formerly controverted. I have no space in this note to give you an account of my observations, and it is unnecessary as you will shortly see an abstract of them in the next number of the Proceedings of the Geol. Soc. I shall therefore merely say that I find in the Crag of Norfolk, which is a fluvis-marine deposit, & containing many bones of mammalia, 60 per cent of recent species (Older Pliocene); in the Red Crag of Suffolk which is purely marine, only 30 per cent (Miocene); in the coralline crag which you saw at Aldborough, and from which we have more than 300 species of shells, only 19 per cent of living species, which I therefore consider Miocene. After carefully examining the collection of Touraine shells which I obtained from M. Dujardin, consisting of 236 species exclusive of some imperfect ones, I find 26 per cent of recent species. In all these identifications I have been assisted by Mr. George Sowerby, and we have had a very large collection of recent shells to compare with the fossil. Being now therefore induced not only on the ground of the proportional number of recent shells, but also from several other considerations to refer the older crag of Suffolk and the faluns of Touraine to the same Miocene period, I am at a loss to understand how two contemporaneous fauna so near each other as Touraine & Suffolk could contain so few species in common, for I find scarcely any common to both. You say (Bulletin E.8. p.210) that on going north most of the large species of the

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faluns disappear; which species rare wanting in Brittany & the Contentin for example. Could you send me a list of the fossils of the more northern patches of your Touraine formulation that I may see whether the fauna approaches nearer to the Crag in the ensemble of its species; or still better could you send me a collection of the shells & corals of your more northern localities all of which I would return to you after examination. I have always said that it was a great loss for our science when you quitted geology for history, & I have been more than ever sensible of the fact on finding that your original view respecting the age of the Crag of Aldborough was the most correct. On the recommendation of a common friend, M. Pratt, F.G.S. - I wrote lately to M. Le Conte de Vibraye, 10 Rue Verneuil, St. Germains, a Paris, begging him to procure for me some shells from Touraine. I forgot to tell him that corals would be equally interesting and useful. Pray tell him so if you are acquainted with him & should see him – I hope your wife & family are quite well & that you can give us good news of the Prevosts – My wife desires her remembrances & believes us ever most truly yrs ChaLyell 16 Hart Street London May 30-39

P.S. I forgot to ask you whether you do not think that as we have 3 ages of Crag in Norfolk % Suffolk, two Miocene & one Older Pliocene periods, so there may be some shades of chronological difference in the faluns of the Contentin, Brittany & Touraine?