The completion of the 40th volume of the Geological Magazine, and the commencement of its Fifth Decade under the Editorship of one who has been responsibly associated with the undertaking since 1864, and has been Editor-in-chief since July, 1865, furnishes a fit opportunity for a retrospect.

In the opening pages of this Magazine Professor Rupert Jones dealt with “ The Past and Present Aspects of Geology.” He remarked on the tendency to encroach upon the theory of Uniformity, upon the right “to call in the agency of forces which, though not seen in operation in nature, may be evoked in the laboratory.” He further referred to “recent discussions respecting the origin of granite, the mode of formation of river-valleys, the excavation of lake-basins, the doctrine of ‘homotaxis,’ and the origin of species.” At that time, owing to the teachings of Huxley, there was more scepticism than there is now as to the exact truth of “the contemporaneity of strata which contain the same or similar fossils, and which are geographically far apart.”

One of the most striking objects exhibited in the Gallery of Fossil Plant remains in the Geological Department of the British Museum (Natural History) is a large trunk of a Coniferous tree from Tasmania, of which a photograph is reproduced on Plate I. This specimen is one of the largest in the gallery, being nearly nine feet in height, and three feet in diameter. The woody tissues are in excellent preservation, the specimen being silicified, and in part opalized.

In the course of repeated visits to Corsica I have been much struck by the extraordinary erosion, not only of cliffs, but even more so of detached masses or boulders, from near sea-level to heights of 5,000 to 6,000 feet; and, having taken some photographs last January of specimens of the kind last referred to, I sent them to my friend Professor Bonney, who informed me that he had never met with any instances of erosion of such a peculiar and unusual character, and asked whether I could furnish him with a fragment of the rock.

It may be of interest to note the occurrence of a somewhat rare and interesting rock, named keratophyre, at two easily accessible localities in a district where it has been hitherto unknown—at Moel-y-Golfa, in the Breidden Hills, and in the Berwyn Hills.

The Breidden Hills.

Moel-y-Golfa was visited by me in 1899, and I collected a few specimens, which, however, remained unexamined until a few days ago when I needed one for teaching purposes. On examination of a thin section the plagioclase proved to be albite, idiomorphic and tabular in form, set in a matrix of chloritic decomposition products, doubtless the remains of pyroxene. The ratio of albite to pyroxene must have been about two or three to one. This composition is sufficient to place the rock in the keratophyre group, but confirmation was obtained by comparison with a slide of the well-known keratophyre of Hüttenrode, in the Harz, the rocks proving almost identical both in structure and composition. The determination of the felspar was made by Becke's bright line method, which proved its refractive index to be everywhere slightly lower than that of balsam.

The occurrence of small quantities of chert and opal, usually in or near exposures of crystalline limestone, but very often in fragments or boulders not quite in sitû, is not unusual in Ceylon. For some time the origin of these siliceous rocks remained obscure; observations made within the present year (1903), however, enable me to give a more detailed account of their mode of occurrence. I have had the advantage of my colleague Mr. James Parsons' company in examining many of the exposures, and have been able to discuss with him the problems raised.

On the top of the cliff between Headon Hill and Widdick Chine, in Totland Bay, there is a Recent tufaceous deposit containing land and fresh-water shells. It extends along the cliff for nearly 350 yards in a north-easterly direction from the base of Headon Hill, and is about 60 feet above the sea-level.

It was first described by Mr. Joshua Trimmer, and subsequently by Professor Edward Forbes and Mr. H. W. Bristow. In the more recent memoir on the Isle of Wight the earlier descriptions are quoted, but the section is described as being then almost entirely overgrown.

Four articles in the Biarritz Association Bulletin, and a series in the last publications of the Soc. Géol. de Fiance, discuss the problem of Pyrenean ophite by conjectures regarding the obscure points of greenstone in the shifting sands of the Biarritz coast. When first seeking new facts at Biarritz, I discovered the red marls and gypsum that accompany the ophite to be recurrent in the undisputed Upper Cretaceous of Croix d'Ahetze, and I followed the Biarritz rocks to Zumaya and Loyola in the attempt to trace their relations. Having subsequently proved that the other red clays mapped as Trias are brick clay of post-Glacial origin, contemporary with a tooth of Elephas primigenius and anterior to flint implements described as Pliocene, and having vainly demonstrated the continuity of the rocks of the Spanish coast by both maps and fossils, I would invite geologists to profit by the light railways and other advantages which to-day enable the fundamental section of Pyrenean geology to be easily studied in its unmistakable continuation.

In criticising my paper Professor Hull “regrets very much to have found it necessary to make these remarks.” I regret it too, because he only raises issues whioh have been discussed, and, I hoped, settled years ago. But I fear that Professor Hull has not given attention to modern Jurassic literature. He says that Midford Sands is “a name unknown to geologists in general.” Whereas, as the Editor points out, Professor Phillips was the author who amused himself with inventing this fanciful name, to adopt my critic's language. And in the 1879 edition of Sheet 44, at the foot of which appears the name E. Hull, there is on the margin this legend, “G 4, Midford Sand.”

In 1844, in his “Synopsis of the Carboniferous Fossils of Ireland,” F. M'Coy described and figured the species Goniatites fasciculatus (p. 13, pl. ii, fig. 8), a Goniatite referable to the genus Pericyclus, Mojsisovics. The type-specimen is preserved in the “Griffith Collection” in the Museum of Science and Art, Dublin, and has been re-figured (as Pericyclus fasciculatus) by Dr. A. H. Foord in his “Monograph on the Carboniferous Cephalopoda of Ireland” (pt. iv, 1901, pl. xxxvii, figs. 5a, b); where its locality is given as Millicent, Clane, county of Kildare.