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PALÆONTOLOGICAL NOTES.
By Thomas Davidson, Esq., F.R.S., F.G.S.
I. ON SCOTTISH JURASSIC BRACHIOPODA.
So little is known of Scottish Jurassic Brachiopoda, that any additional information cannot fail to prove interesting. Professor Nicol wrote me on the 16th of April, 1860, that out of a pretty large collection of the fossils of this period sent up to the Aberdeen meeting of the British Association, he found only two species and specimens of Brachiopoda, and both imperfect. That in Sunderland they are most common in the Dunrobin Reefs (by some thought to be Oxford clay, by others Lias), but that the stone is so friable, that the specimens fall to pieces almost at the slightest touch; and that in the sandstone at Braambury Hill, are casts of a large shell, like Terebratula perovalis, but often crushed and distorted.
In 1850, the late A. Robertson, of Elgin, sent me two beautifully preserved Rhynchonellæ (B. lacunosa?), from Dunrobin, and which will be found figured and described in my monograph ; and about the same period, the late Hugh Miller sent me a specimen of T. numismalis, from the Lias of Shendwick, and another of Rhynchonella Bouchardii, from the Lias of Cromarty. Mr. Geikie recorded likewise a Rhynchonella tetrahedra, from the Middle Lias of the island of Pabba.
It would result from the above statement, that about six species of Brachiopoda have, up to the present period, been mentioned as having been found in Scottish Jurassic strata.
On the 9th of April, 1860, Captain E. J. Bedford, R.N., informed me that while surveying the island of Mull, he discovered a great number of fossils in the Middle Lias of Caisaig Bay; these he kindly forwarded for my examination, and I found among many other Mollusca, eight or nine species of Brachiopoda, two of which being new to Scotland, and one even so to Great Britain.
I was informed, at the same time, that these fossils had been all cut out of a hardened kind of black clay, uncovered at low water; that this clay lay in laminæ, which he lifted up with a little bar, and in which he found all the specimens sent up, with the exception of Terebratula punctata and some other species of Mollusca, which he obtained from hard masses of limestone scattered about the shore.
The following is a list of the Mollusca from the Middle Lias of the island of Mull, which Mr. Etheridge and myself were able to determine:—
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Terebratula punctata. |
Rhynchonella rimosa. |
