In the former notes “On the growth of soil,” I omitted to speak of the labours of the ants—these workers, although such pigmys in this country, and, therefore, compared with the earth-worms, less capable, individually, of work, are so numerous and energetic, that in the special places to which they resort, their yearly work is much more conspicuous than the annual worm-work; but the animals operate in different places, for while the earth-worm luxuriates in rich highly-cultivated land, the hill-building-ant loves a dry, sandy or peaty soil. In the spring the ants may be observed beginning their work, and from that time they carry on their operations all through the summer, to the late autumn, or early winter. On a moor they raise hillocks scattered promiscuously about over the ground, getting closer and closer together as the colonies increase. But where the ants are most useful is in places where crags and large stones are mixed up with patches of sandy peat. In such a locality they will always build on a rock, the foundation of their habitation being at its junction with the soil. These ants seldom raise their structures as high as the moorland ants, but they make up in extent for absence in height, and by this means the rocks are gradually covered with soil and vegetation; for, on account of the season of the year at which they build, the growth of the plants keeps pace with the formation of the ant-soil, and protects it in a great measure from “Meteoric abrasion.” During the winter, however, the shape of the ant-hills is somewhat modified, but the matted roots of the plants preserve the major part of the soil which will thus remain, forming an envelope for the rock.

The August number of the Quaterly Journal of the Geological Society contains a paper on this subject by Dr. J. W. Spencer, who believes that the rocks which were described by us under the head of ‘Raised Coral Reefs’ do not form one continuous succession of Pleistocene reef-rocks, but consist of several different limestone formations. He thinks that there are three such formations, and that each is separated from the other by a break or unconformity.

A new interpretation of a polygonal pattern of ridges in the Marble Hill Dolomitic Limestone, at Ballymore, suggests that it was formed by a soft-bodied, worm-like organism.

Four species of Monograptus are described and the age of the strata shown to be that of the zone of M. nilssoni of the Lower Ludlow of Great Britain.

The Swedish Magellanic Expedition spent some time in the Falkland Islands before proceeding to Tierra del Fuego, where important work is being carried on. The writer utilised his stay in the Falklands to study the geology and collect fossils. The following is a brief note of the work there.

In the first part of this paper an account has been given of the heavy minerals of the northern part of the Leinster Granite and of the contiguous rocks in the Ballycorus district.

The section exposing this stratum was discovered during an excursion made last June by Mr. W. Hill, F.G.S., and the author. It occurs in a quarry near West Row Ferry, about two miles west of Mildenhall;here a band of red marly chalk is seen near the entrance, dipping westward at a low angle, hut soon becoming horizontal and running along the whole face of the quarry, till it is cut off by a fault, which brings up lower beds on the southern side.

3. Third Period of Volcanic Activity in the Lipari Islands.

Although, as we have already seen, the older volcanic formations of the Liparis present us with features of no little interest, yet it is on account of the cones and lava-streams, composed of rocks of singular beauty and almost unique character,—which are the product of the latest developments of igneous action in these islands, that the attention of geologists is most frequently directed to them.

Recently, when examining some weathered fossiliferous limestone shale from the Lower Carboniferous strata of East Kilbride, Lanarkshire, my attention was attracted to some fragments of the valves of Spirifera trigonalis, Martin, in which I noticed, on the hinge-line of the dorsal valve, a row of small, round, hollow pits, and on the hinge-line of the ventral valve, a corresponding row of small, projecting, rounded denticles. These characters I had not noticed before, and on searching further, I found other fragments of the valves showing the same thing. This led to an examination of more perfect specimens of this Spirifera, contained in my own collection, and that of Dr. J. R. S. Hunter, of Braidwood, Carluke, and in one example, where the valves had slightly opened through pressure, on clearing away the shale, I found, on the outer edge of the ventral valve, a distinct row of small projecting denticles, that had evidently fitted into hollow pits or sockets in the dorsal valve, but from the way the valves had shifted in this specimen these were not seen. These denticles, when looked at externally, are nearly as numerous, and much of the same size, as those seen in many of the hinge-lines of shells of the genus Area, only in this genus, the teeth are the same in each valve, and lock into each other.

In a former article I endeavoured to show that the more abrupt inequalities of the earth's surface, so far as they consist of escarpments with their associated phenomena, are chiefly due to the former action of the sea. Before proceeding to consider the origin of Valleys, I find it necessary to refer to a statement I made in the last article about Raised Beaches (page 69). My object was merely to show that the preservation of numerous terraces in the Cretaceous districts of Wilts and Dorset furnished an evidence of limited subaërial denudation since these terraces were formed. The terraces to which I alluded, principally occur at comparatively low levels; and that they are raised beaches can, I think, be clearly proved. But this is not necessary, so far as the present controversy is concerned; for the preservation of terraces in gravel (more easily worn away than chalk, according to the subaërialists), which all admit are either raised sea-beaches, or glacial-lake-beaches (such as those of Glenroy), afford an equally convincing proof of the impotence of rain as a denuding agent.

The descriptions of two of the species enumerated in my paper on the Tertiary Fossils of the West Indies having been accidentally omitted, the defect is now supplied.

A small mass consisting of three intrusions of fine-textured acid rocks occurs within the basaltic agglomerates of the Kilchrist Vent of Tertiary age. One of the intrusions comprises flow-layered rhyolite and ignimbrite. It is thought that the rock-types represent two distinctive eruptive waves. A form of ovoidal structure not seen elsewhere in the Kilchrist area occurs in another rhyolite intrusion.

The specimen herein described was sent me by Mr. T. S. Hall, M.A., of Melbourne University. It was found by Mr. F. P. Spry in a rock of supposed Silurian age, at the Yarra Improvement Works, near Prince's Bridge, Melbourne, in November, 1896. The matrix is a fine-grained micaceous sandstone, of a dark purplegrey, weathering yellowish. It often contains crinoid columnals, such as were long ago noticed by the Geological Survey of Victoria, and were figured by W. Blandowski as “Cyatocrinites (probably)pinnatus”; but neither from here, nor from any other Silurian rock of Australia, has a crinoid crown hitherto been recoi-ded. The remains of the crinoid are in the form of an impression, coloured red by iron-oxide; all calcareous matter has been dissolved away. The counterpart of the impression has not been preserved. The specimen was studied by means of wax squeezes; the drawing (Plate XV) represents such a squeeze; and the description follows the drawing.

Charges of Fe-tremolite, sulphur and water sealed in gold capsules and run at 600°C and 1 kb confining pressure for one month yielded talc, anhydrite, pyrite and quartz as principal mineral phases. It is concluded that in a S-rich environment talc is stabilized rather than diopside by the strong preference of Ca to form anhydrite.

Small species of Chonetes are frequently found crowding the limestones in the lower part of the Avonian Succession round Bristol and in the Mendips. Of these Ch. cf. hardrensis (Phill.) is the most persistently abundant throughout its range Km-Zl, but the two other species, Ch.failmulensis sp. nov. and Ch. stoddarti, Vaughan, here mentioned, occur in equally large numbers at particular levels within that horizon. The following notes are the outcome of the study of the material recently collected by Professor S. H. Reynolds, and myself, at St. Monica's Home of Rest, Westbury-on-Trym, but this has been considerably supplemented by specimens obtained from other localities in the district.