Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/711

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Plate XXXIV.

Figs. 1-4. New Mastodon from the Suffolk Bone-bed.

Fig. 1. Enamel crown of a left upper penultimate molar of a Trilophodont Mastodon, with simple valleys between the primary ridges, from the Suffolk Bone-bed. Diestien matrix fills up the valleys. In the collection of Mr. Baker, of Woodbridge.

Fig. 2. Side view of the same tooth.

Fig. 3. Fragment consisting of two terminal ridges of a similar tooth, probably a lower molar, from the Suffolk Bone-bed. In the collection of the Rev. H. Canham, of Waldringfield.

Fig. 4. Fragment of another tooth, exhibiting a slightly oblique secondary transverse ridge or fold of enamel (t r) crossing the valley, and hence similar to Mastodon (Trilophodon) tapiroides. In the collection of the Rev. H. Canham.

Fig. 5. Conus, sp. A gutta-percha pressing from a concave cast in one of the Suffolk Box-stones. The nodule is in the collection of the Rev. H. Canham ; the pressing is in the Society's cabinet.

Fig. 6. Voluta auris-leporis. A natural cast in Diestien sandstone from the Suffolk Bone-bed. In the collection of the Rev. H. Canham.

Fig. 7. A large and flat Venus, from a gutta-percha pressing taken from a concave cast, in a Suffolk Box-stone. The nodule is in the Rev. H. Canham's collection ; the pressing is placed in the Society's cabinet.

Fig. 8. Natural cast of the interior of a small species of Cassidaria, occurring in a Suffolk Box-stone. In Mr. Canham's collection.

Fig. 9. Gutta-percha pressing from the concave cast of a similar shell, showing the form of the apex of the shell and its surface-markings. In a Box- stone belonging to the Rev. H. Canham.

Fig. 10. Isocardia lunulata. An abundant form in the Belgian Black Crag, not uncommon in the Suffolk Box-stones. Gutta-percha pressing from a nodule belonging to the Rev. H. Canham.

Discussion.

Mr. Boyd Dawkins had arrived at a different conclusion from the author, though the discoveries recorded in works on palaeontology showed a marked difference between the Suffolk and Norfolk Crag-faunas, such as was not borne out by an examination of collections. He considered that the forms of Ruminants showed a contemporaneity between them. The supposed Cervus dicranoceros of Owen was, in fact, another form of deer, which was common to the base of both the Suffolk and Norfolk crags. The Elephas meridionalis and Mastodon arvernensis had been found side by side in Norfolk, at Montpellier, and in the Val d'Arno, and were therefore probably contemporary. The different lithological character in the two counties was probably due to the different nature of the underlying beds — London Clay and Chalk.

Sir Charles Lyell was much struck with the perfect identity between the box-stones of Suffolk and some exceptional Antwerp beds which he had seen at Berchem, and considered that this was sufficient to prove they belonged to the same deposit. He thought that the area between Belgium and England might have contained a large number of terrestrial beds which eventually left a certain number of their contents to be mingled together in the lower beds of the later marine deposits.

The Rev. J. Gunn produced from the Red Crag at Waldringfield