Mr. Sollas had examined sections of the fossils from the Cambridge beds under the microscope, but had failed to find the canals or tuberculated spicules characteristic of Alcyonaria. He had, however, in the sand found numerous indisputable sponge-spicules. He had, moreover, found in sections of the coprolites spicules such as were regarded by Dr. Bowerbank as characteristic of sponges. He hoped, however, to recur to the subject. Both Mr. Fisher and himself concurred in removing these nodules from the category of concretions, and placing them under the head of organic fossils. The transported blocks in the beds bear evidence of glacial action, and, he considered, had been brought from Scotland or Scandinavia. The cold sea then existing at the base of the Scandinavian chain of mountains flowed southward over the bottom of the ocean, carrying with it mineral matter in solution, particularly phosphates; so that in this way, he thought, some portion of the phosphatic matter was derived from the decomposition of the volcanic rocks north of the Lammermuirs, which were rich in this substance, and of which rocks he had found fragments near Cambridge. He considered that, under certain circumstances, the phosphatic matter present in water would combine with animal matter, and hoped at some future time to offer some remarks on this subject to the Society.
June 5, 1872.
Isaac Shone, Esq., of Bersham Hall, near Wrexham, Denbighshire, was elected a Fellow, and Prof. J. D. Whitney, of Cambridge, U.S., a Foreign Correspondent of the Society.
The following communications were read:—
(Communicated by E. Etheridge, Esq.)
Whilst accompanying Mr. T. D. Forsyth to Yarkand in the summer of 1870, we came upon extensive tracts of ground indented with very remarkable circular pits, which I was very much puzzled to account for.
Where first seen, they appeared like the holes made in washing for gold, as practised both in Tibet and Yarkand; but there was none of the excavated material to be seen round their margins, and they were a hundred miles or more from any human habitation; besides, they were much too regular in size and shape to be thus accounted for.
I noted at the time every circumstance which I thought likely to give a clue to the manner of their formation; but, from the rapidity
