When in Rio de Janeiro last October, Dr. Orville A. Derby gave me for publication in the GEOLOGICAL MAGAZINE the photograph of a fine new specimen of Stereosternum tumidum, reproduced in the accompanying Plate V. Like the type-specimens discovered by Dr. Derby, it was obtained from a light-grey limestone in a quarry on the estate of Senhor Antonio Machado de Campos, near the town of Limeira, in the State of San Paulo, Brazil. It is interesting as showing for the first time the general proportions of the trunk and tail of this strange extinct reptile; and it also permits the identification of another fossil from the same formation, now in the British Museum, which has hitherto escaped notice.

The shell to which I have given the above name is at present unique. It was found, a few years ago, in a quarry at Clane, in the county of Kildare, where I had for some time been in search of Cephalopod shells. It was associated with characteristic species of Carboniferous Limestone fossils, among which the following Nautiloid shells may be mentioned, viz. Solenocheilus dorsalis, Phil., sp., Asymptoceras cyclostomus, Phil., sp., A. Foordi, Hyatt, and an undescribed species allied to the last-named one. The marginal spines, at first obscurely seen in the matrix, at once attracted attention; and although one was broken off and lost in the quarry débris, the other was fortunately found in the fragment of rock struck off from the shell, and was then carefully developed and attached to the latter. Naturally very diligent search has been made since its discovery, and a sharp look-out kept for any further specimens of this interesting species, but so far without any result.

A Small series of rocks collected at several localities in the Tonga Islands by Lieutenant J. A. Waugb, R.N., during the voyage of the “Penguin” in 1895, has been forwarded to the Geological Survey for examination, by Admiral Wharton, R.N., F.R.S., Hydrographer to the Admiralty. As in some particulars these rocks supplement those already described by Mr. A. Harker (GKOL. MAG. 1891, p. 250), from the same group of islands, it seems desirable that a short account of them should be placed on record.

Following in the wake of that admirable institution the Boulder Committee of the British Association, whose work ought to have been done by the Geological Surveyors, we may divide the districts from which the foreign boulders (that is, boulders extraneous to the immediate district) have come to Eastern England into four, namely, Charnwood Forest, the Hills of Derbyshire, Durham and Cleveland, and lastly Norway.

The correlation of the various series of Carboniferous rocks which occur in different districts of Great Britain according to the fourfold subdivision proposed by the late Professor Phillips, has always presented great difficulties, on account of the marked changes in sequence, thickness, and lithological character which occur in districts only a few miles apart. The consideration of this difficulty was the subject of a special Sub-Committee of the International Geological Congress of 1888. The Report, however, indicated only a difference of opinion, and consisted chiefly in a series of typical sections showing the local development of Carboniferous rocks, and the schemes of classification proposed by various members of the Sub-Committee.

The recent find by Mr. Stebbing, F.G.S., of two large boulders of granite in the Middle Chalk of Betchworth (Surrey), has called to mind the various discoveries of boulders which had previously been made in the same marine formation by other observers.