The site of Barnwell Abbey has long been excavated for gravel. The pits have been easily accessible to collectors, and have for many years yielded large numbers of Mammalian bones, Mollusca, and a few plant-remains.

These gravels were noticed by the Rev. P. B. Brodie and Prof Sedgwick in 1838. Prof. Seeley gave a sketch of them in the Q. J. G. S. 1866, in which there was a list of the land and freshwater shells drawn up by Mr. Dewick. They were described by Mr. Jukes-Browne in his essay on the Post-Tertiary deposits of Cambridgeshire, 1878, and in the Memoir of the Geological Survey.

During the interval of ten years which has elapsed since my paper on Liassic Madreporaria was read at one of the meetings of the Geological Society, a great many specimens of Liassic Isastrææ and Septastrææ, chiefly from the Vale of Evesham, have come into my hands, and with this abundance of material I have examined a new the several species, and have arrived at the results contained in the present communication. When making these examinations, I have been invariably struck with the absence of a distinct and well defined basal wall and epitheca. Further observation also showed that these Liassic forms differed from other Isastrææ in having occasional elongated calices, like those of Latimæandra.

During Professor Hughes' annual geological excursion, which was last Easter conducted to Ilfracombe, I was much struck with certain structures exhibited by the ordinary Devonian sediments, and some of these are, I think, worthy of a short notice. Most of them are exhibited on the beach close to Ilfracombe, at the bathing place, where there is also seen the folded grit band rendered classical through Dr. Sorby's writings.

Mynydd Mawr, about three miles west of Snowdon, is an abrupt rounded hill, 2300 feet high, separating the valleys of Nantlle and Cwellyn. A reference to the maps of the Geological Survey (75 N.E. and N.W.) shows it to be due to an isolated boss of “intrusive hornblende-porphyry ” in the form of a rounded parallelogram, a mile and a half in its longest diagonal. Dr. Hicks has mapped this patch as Pre-Cambrian, and included it in his Arvonian system; but apart from its position, breaking through a regular succession of Cambrian (or Ordovician) rocks, an examination of the junction affords convincing proof of its intrusive character. On the northern flanks of the hill the relations are well exhibited, and the induration and extensive mineralogical alteration of the slate in the vicinity of the boss are very marked. It is indeed by no means easy to determine on the ground the precise point where the hardened, semicrystalline slate gives place to the porphyry.

In “The Palæozoic Fossils of Canada,” vol. i. p. 3, the late Mr. Billings stated that by treating a silicified specimen of Archæocyathus Minganensis with acid, he ascertained that it contained numerous siliceous spicula—slender, fusiform, slightly curved, acute at both extremities—and that these fossils must therefore be classified among the extinct tribes of sponges. Referring again to this species in the latter part of the same volume (pp. 354–357), this author states that he had found the same spicula present in great numbers in another large species, Trichospongia sericea, and that it therefore remained an open question whether they actually form part of the structure of Archæocyathus, or belonged to Trichospongia.