Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/476

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(1) White chalk about 40 feet seen.

(2) Pale- red chalk, with red-clay partings. Crowded

                                                     thickness uncertain, 

with specimens of Belemnites minimus, List.

(3) Dark-blue clay, full of fossils.

According to the concurrent testimony of a number of reliable witnesses, this pit yielded immense numbers of beautiful Ammonites, mineralized by pyrites, with many Belemnites, and other shells, and was the source of the numerous fossils which found their way to the various Yorkshire museums and were labelled as Knapton fossils. From a consideration of all the evidence on the subject, I think there can be no doubt that this pit was opened in the highly fossiliferous zone of Ammonites speetonensis. The pit is now completely closed, and the bottom planted with trees.

A mile further to the west, and about half a mile south of the village of East Knapton, are found two other very interesting pits. The most easterly of these exhibits the following succession of beds : —

(1) Hard white chalk with a few flints.

(2) Red chalk, crowded with Belemnites minimus, List.

(3) Black shaly clay with dark-coloured septaria, containing numerous veins of calc-spar ; this clay was formerly dug to a very considerable depth.

In the clay itself, which is badly exposed at the present time, no fossils could be detected ; but in the septaria, thrown out from this pit when it was worked, numerous specimens of Ammonites were obtained. These were all Lower-Neocomian species, Ammonites fascicularis, D'Orb. (a shell known locally under the manuscript name of A. evalidus, Bean), being especially abundant. In my memoir on the Speeton section, I have not introduced this Ammonite into my lists, not having found it in situ ; but my friend Mr. Leckenby assures me that the numerous specimens of this shell in his own and other collections were all obtained from argillaceous nodules in the beds exposed at low water on Speeton shore, and but very little above the beds containing the Portlandian species.

In the second pit at Knapton, which is only about 100 yards to the westward of the former, we find the following beds : —

(1) Hard white chalk with a few flints.

(2) Light-red chalk full of Belemnites minimus, List.

(3) Dark-blue clays, very pyritous, containing many small brown fragments of ironstone.

This clay, from its pyritous character and long exposure to atmospheric influences, is now crowded with beautiful crystals of selenite. I could find no fossils here ; but if such originally existed in the beds, they must long since have perished, owing to the quantity of pyrites in the clay.

The most interesting circumstance, however, in connexion with this pit is, that at some little distance from the surface a layer of phosphatic nodules, about 6 inches thick, was discovered by the late Mr. Tyndall, of Knapton Hall. The value and importance of this discovery were not lost upon William Smith, who, then a resident