The bones of the carapace and plastron from which this species has been determined were discovered in a thin seam of grey sand intercalated in the Mammalian band of the Lower Headon Beds at Hordwell, Hampshire. They were lying scattered over an area of about four feet. The broken edge of the entoplastral and right hyoplastral were sticking out of the cliff face. The sea had carried away the missing portions of these bones and probably those lost of the carapace and plastron.

The structures described in this note occur in a large chalk-pit close to Hensting Farm, by Owlesbury, near Winchester. The east face is vertical, about forty feet high; near the bottom, along a well-marked bed of the Chalk, some deposits of gravel and clay are exposed at varying distances from each other; three of these are small, two rather larger. On the south face there is a similar deposit near the top of the pit, but this is inaccessible, and no special structure can be seen in the surrounding Chalk owing to its conversion into subsoil.

This important Coal-measure zonal Lamellibranch has already been recorded from the Yorkshire and Nottingham Coalfield (Cadeby and Gedling Colliery respectively), the Lancashire Coal-field (Ardwick, Manchester), the North Staffordshire Coalfield generally, the Forest of Dean and Bristol Coalfields, the South Wales Coalfield; and in all these widely separated districts it is found at the top of that portion of the Coal-measures characterised by the presence of the most valuable seams of coal.

The family of Trilobites termed Phacopidæ has been defined by Beecher as follows:—“Glabella tumid, widest in front. Free cheeks continuous, united anteriorly. Suture extending from in front of the genal angles inward to the eyes, and thence forward around the glabella. Eyes generally large, always with distinct facets, schizochroal. Thorax of eleven segments with grooved pleura. Pygidium usually large and of many segments; limb ribbed; margin entire or dentate.”

The term ‘earth-shake’ has been applied to local disturbances of the earth which owe their origin, either in part or wholly, to artificial causes. Typical examples of earth-shakes are those which are occasionally felt at Sunderland and other places on the magnesian limestone of the Durham coast, and which have been attributed by Prof. Lebour to rock-falls in underground channels, enlarged no doubt by pumping in connection with the local water-supply. Other examples are the shocks frequently felt in mining districts, and either caused or precipitated by mining operations. Earth-shakes of this class have occurred in the Rhondda Valley in Glamorganshire on June 22, 1889, April 11 and May 2, 1894, and October 16,1896; in the neighbourhood of Camborne on June 4 and 10, 1902; at Pendleton, near Manchester, on February 27, 1899, and April 7, 1900; at Kilsyth in Stirlingshire on February 16, 1898, and in various other districts.

In 1895 the author visited the Prince Albert Goldfields, and later the Millwood Goldfields in Knysna, and has had the subject constantly before him till quite recently, when, in reviewing the whole question in connection with the geology of the region, which he has now worked out under the auspices of the Geological Commission of the Colony of the Cape of Good Hope, he was able to come to some definite conclusions. The gradual building up of convictions on a subject like this, as facts became clearer with increased knowledge derived from the reports of prospectors, the progress of the Survey, and the access to literature bearing on kindred questions, led to the acceptance of certain general principles, which the author has thought worth while to state in definite form for criticism. The peculiar points in the occurrence of the precious metal in these localities cause them to rank high as fields for research, if not for general enrichment of the inhabitants of the Cape Colony.

Unsolved geological problems, or what perhaps may be better described as obscure points in geological history round which conflicting hypotheses have arisen, are to be found in many parts of our Islands, but Devonshire seems to be an usually prolific field for them. Mr. W. H. Hudleston, F.R.S., in his presidential address to the Devonshire Association in 1889, enumerates nine questions propounded by Pengelly in 1868 as still requiring special consideration in the future. Of these possibly three may be said to have nearly or quite got beyond the controversial stage, but in the meantime others have arisen, and it would thus appear that the undecided position of numerous points demanding further investigation is the normal condition of a science in the developmental stage.

Kuchavelli is twenty-two miles north of Trincomalee on the JV. east coast of Ceylon. Two miles south of Kuchavelli is the mouth of the Salape aru. On the right bank of this river, near the mouth, raised beach, consisting of shelly sandstone, is exposed. The sandstone is often full of marine shells, and there are also thick growths of oysters attached to upstanding masses of rock. The bed is from 6inches to 2 feet in thickness, and is exposed about 1 foot above high-water mark, and stretches down the sloping bank between tide-marks. This is the ordinary raised beach of Ceylon, a deposit usuallyoccurring at or below high-water mark, and now being continually eroded at numerous points on the coast of Ceylon where it is exposed (e.g. Bentota). This deposit will not now be further spoken of.

The Salape aru is really the name of the estuary of several rivers; proceeding up the river inland, the Matti aru is reached, a shallow river with alluvial banks eight or ten feet above the water on either side. Extensive sandbanks are found on one side or the other of the river, alternating on the meanders with places where erosion is in progress. These banks are covered with marine shells, the large flat Placunas being most common. There are also found clayey nodules including marine shells, crabs, and it is said sometimes tortoises and fishes. The crabs are collected for use as medicine, being powdered and mixed with milk or water as a specific for diabetes.

In North and South America and in South Africa there is a considerable variety of types of the Dalmaniles-branch in the Devonian period which have in many cases received distinctive subgeneric names; but species retaining the typical characters of the Silurian forms persist at any rate in North America. Many of these Devonian forms show incomplete second lateral furrows on the glabella, these furrows not reaching the axial furrows and causing a partial coalescence of the two middle lateral lobes. This tendency towards the fusion of the first and second lateral lobes of the glabella is a departure from the perfect segmentation found in typical Silurian members of Dalmanites, and has caused Clarke to group all such forms together into the subgenus or section Synphoria. This type of structure, as Van Ingen has recently shown, is not unknown amongst the Silurian species of Dalmanites in America, but it finds its most pronounced development in Devonian time and occurs in the groups Coronura, Corycephalus, Odontocephalus, and Probolium, all of which are put by Clarke in the section Synphoria. The marginal ornamentation and different processes on the pygidium and head-shield on which these four groups have been founded are scarcely of the same structural importance as the modifications of the glabellar segmentation. As in other families, the spinosity of these forms is the symbol of a last expiring effort before extinction.

Since the year 1871 I have been much impressed with the interest and importance of one of the byways of science, the problem of the Geological Physios of the Shallow Seas. Recent discoveries in raised beaches have brought this subject again to the front, and the object of the present paper is to plead for further inquiry by specialists.

I may briefly mention my own now antiquated papers, viz., “Notes on Torbay” (Trans. Dev. Assoc., 1878); “The Formation of Ripple-mark” (Proc. Roy. Soc., 1882); “The Action of Waves on Sea Beaches and Sea Bottoms” (Roy. Dublin Soc., 1885); and “On the Influence of Wave-currents on the Fauna inhabiting Shallow Seas” (Journ. Linn. Soc., 1884). With the exception of the Dublin paper, the MSS. were, as a matter of fact, perused by eminent mathematicians, who kindly guarded me against any conflict between observation and theory.