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.

At the heart of Africa lies a vast area, so remote, so inaccessible, and hence so little known, that for the explorer it possesses a fascination all its own. The interests of the geologist have perhaps received less recognition than those of his fellow-scientists from the pen of the traveller; and there must be much that he would wish to know lying hidden in these distant regions awaiting discovery and publication. There is thus an encouragement to make known any facts which may throw light upon the geological structure of those parts, however small the contribution may be.

While serving recently with the Anglo-French Boundary Commission (Niger-Chad) we found an outcrop of a fossil-bearing stratum in the region of the Sokoto, having, as shown in the accompanying map, giving its latitude and longitude, a position near the verge of the Great Sahara Desert. On my return, the specimens secured were submitted to the palæontologists of the British Museum, one of whom, Dr. F. A. Bather, has kindly drawn up the description which follows in a separate paper. For me it only remains to give a few particulars of the general and localized formation to supplement his account.

Generally, the country consists of sandy plains, roughly estimated as lying some 500 or 600 feet above sea-level. These plains are traversed by watercourses, which contain running water only for some five or six weeks in the year, the rainfall of 535 mm. lasting during three months. A permanent water-supply is obtained by deep wells, which in some places reach a depth of 400 feet before tapping a constant source.

The study of Egyptian geology during the last few years has thrown a flood of light on the former extension of the Mediterranean southward in Miocene times. Th. Fuchs, in examining the rich collections from the Cairo-Suez desert and the oasis of Siwah, recognized that the Miocene strata had a close resemblance to those of the Vienna Basin, and corresponded to the Grunder Beds at the base of the second Mediterranean stage, or the lower portion of the Middle Miocene. Later L. H. Mitchell, when studying the neighbourhood of Ras Jemsa and Jebel Zeit in 1887, obtained a number of large oysters, which Meyer-Eyinar recognized as Ostrea crassissima and Ostrea giganlea, and which were regarded as proving the existence of strata of Upper Miocene age along the western border of the Suez Gulf. From these results Blanckenhorn concluded that the Gulf of Suez must have been a Mediterranean bay in Miocene times, and further noted (Zeitsch. Deutsch. Geol. Gesell., Band liii, 1901, p. 79) that characteristic Miocene Pectens, viz. Pecten Sub-Malvinœ, occurred in the collection made by Barron at Abu Sha'ar. He further formed the opinion that all the marine Miocene strata in Egypt were of the age assigned to them by Fuchs (see also Barron & Hume, “Miocene Rocks in Eastern Desert,” Memoir of Egypt. Geol. Surv., 1902, pp. 159–165).

In the Geological Magazine, August, 1904, pp. 392–403, Dr. Wheelton Hind describes the Lower Culm beds of North Devon and assigns them to the ‘Pendleside’ series.

From the original paper dealing with that series I gather that in the North of England the ‘Pendleside’ beds lie above the uppermost zone of the Carboniferous Limestone, and are the equivalents of the Millstone Grit of the South Wales and Mendip areas. Dr. Hind's contention is, then, that the Lower Culm of North Devon was laid down at a time subsequent to the deposition of the whole of the Carboniferous Limestone of the Mendips and South Wales.

In the broad Alluvial tract which borders the Ouse between Oakley and Clapham, north of Bedford, there is a gravel-pit in which a small anticline of the Great Oolite was abruptly encountered amidst the regularly stratified river-deposits. The pit is situated immediately north of the Oakley road and east of the Midland Railway.

I am glad that my paper on the Coddon Hill beds, published in the Geological Magazine, August, 1904, pp. 392–403, has aroused criticism, and could only have wished that Dr. Vaughan had been familiar with the Carboniferous sequence of the Pennine area and Belgium. The matter is not one to be solved by the casual appearance in any definite bed of a few Brachiopods, at one only of the many horizons at which they are known to occur in other localities, for the whole of the fossils, which are quoted by Dr. Vaughan as the foundation for his argument that the Coddon Hill Beds are low down in the Carboniferous sequence, are equivocal as far as their value as zone indices goes. And on the other hand, Dr. Vaughan completely ignores those fossils which are unequivocal and which denote a well-recognised horizon, and curiously enough, too, correspond with a marked change in lithological character of the Carboniferous sequence. In the first place, I do not see where Dr. Vaughan found any statement in Mr. Howe's and my paper on the Pendleside group at Pendle Hill (Q. J. G. S., vol. lvii) that the Pendleside series are the equivalents of the Millstone Grit of South Wales and the Mendip areas. The table on the page quoted (p. 388) distinctly shows that we consider the Pendleside series to lie universally below beds equivalent to Millstone Grit, and we do not mention the series of the Bristol and Mendip area because we were not well enough acquainted with that district to do so.

It is fortunate that Captain Lelean not merely discovered these fossils at Garadimi in Sokoto, but that he had enough sense of their importance to spend some time and trouble in their collection, and that now he has generously presented them to the British Museum. The collection includes four echinoid tests, five natural casts of Mollusca, and a few rock-specimens containing Operculina and other Foraminifera. The Mollusca, so far as their state of preservation admits, have been determined by Mr. R. Bullen Newton as: 3 Lucina cf. gigantea Deshayes, 1 Voluta cf. cithara Lamarck, and 1 undetermined Gastropod. The Echinoidea were partly covered by an impure limestone closely adherent to the test. The portions not so covered were in many places considerably worn, and the calcite was split by cracks, probably due to alternations of temperature, and rendering it very difficult to follow the course of the sutures. The appearance of these and the other specimens shows clearly that they have been lying on the surface of the ground for some time, and, in fact, Captain Lelean informs me that they were not picked out of the solid rock, but from the talus at the foot of the cliff. The notable variations in the matrix of the different specimens are thus accounted for. None the less it will be seen in the sequel that all the specimens are consistent with the ascription of a Middle Eocene age to the mass of limestone from which they were derived. Of the four echinoids, two have been determined as belonging to the genus Plesiolampas and two to the genus Hemiaster.

In the paper on the Pendleside group at Pendle Hill, Q.J.G.S., vol. lvii, p. 377, I said, “The further facts of the distribution of Glyphioceras spirale and Posidonomya Becheri set forth in the fore-going pages open up the wide question of the age of the Culm beds of Devon and Germany.” Since then I have had the great advantage of examining suites of fossils from the Lower Culm of Devonshire, collected by Mr. Hamling, of Barnstaple, and Mr. Coom´rasw´my, from the Coddon Hill Beds and other localities in North Devon. I was so interested in the fossils that I found it necessary to go down and examine the beds in which they occurred, and Mr. Hamling gave me the inestimable advantage of his guidance. In this way we examined the Lower Culm and the underlying Pilton Beds in detail from West Leigh to Fremington, and the so-called Middle Culm of Bideford and other places. I was able to see the Hall collection of fossils at Barnstaple, and again to renew my acquaintance with Mr. Hamling's collection. This visit to Devonshire, it seems to me, was fortunately planned after a visit last Summer to the Devono-Carbonif'erous succession in the south-west of Ireland, and a study of the fauna in the collection of the Geological Survey at Dublin and in the Museum of Queen's College, Cork.

Among the collections now in Cairo I find several new mammals, the remains of which have been collected by Mr. Beadnell, for the most part during the last few months. Brief descriptions of these new forms are now given in order that the names may be included in the lists in Mr. Beadnell's forthcoming report on the geology of the Fayûm area.

Pterodon macrognathus, sp. nov.

This creodont is known from the nearly complete left ramus of the mandible. The last molar, the first premolar, and the incisors are represented by the alveoli only, but the other teeth, with the exception of the canine, the crown of which is broken off, are in fairly good condition. The mandible is long and narrow from above downwards, the distance between the last tooth and the condyle being remarkably great. The transversely elongated cylindrical condyle is about on a level with the alveolar border, and is separated from the prominent angle by a deep notch; the coronoid region is imperfect.

During the last few months I have been engaged in examining the remains of the fossil Vertebrates from the Middle and Upper Eocene of the Fay ûm district of Egypt, with a view to the preparation of the detailed monograph which it is proposed to publish on this subject. As it will be some months before this can appear, it seems desirable to give a brief account of some of the more important results arrived at, and preliminary descriptions of such new forms as have come to light in the course of the work. The collections examined include all the material belonging to the British Museum, as well as many of the more important specimens from the Geological Museum of Cairo. There still remains in Cairo a large collection of bones, which I hope to have an opportunity of working out during the next few weeks.

As is well known, all pterodactyls have three small, unguiculate fingers on the radial side of the patagial finger, evidently used in the support of the body, possibly also in prehension and ambulation. In the older forms these fingers were relatively much better developed than in the later ones, the metacarpals of the former, of considerable strength, all articulating with the carpus, whereas in the more specialized forms of later geological age the proximal ends of these bones had become either greatly attenuated or entirely lost. In Nyctosaurus, for instance, the very small anterior metacarpals were not more than one-eighth of the length of the wing-metacarpal, and were in life loosely attached by the soft parts only to the distal part of that bone.

The object of this communication is to record some recently-made notes on the Rhætic beds of the neighbourhood of Charfield.

In 1876 Mr. H. B. Woodward, F. R. S., wrote: “Turning to the esearpment of Penarth beds between Tites Point and Wickwar, we find them exposed in many places. Long ago Sir Roderick Murchison stated that ‘passages from the Lias into the underlying New Red Sandstone can be observed in the sides of Whitecliff Park Hills, south of Berkeley; but the clearest and best instances are to the east of Wickwar, near Sturt Bridge, on the sides of the new road ascending to Wotton.'” This is all that has been written on the area now under consideration. As is well known, the junction of the Rhætic and Keuper Series is usually marked by a low but distinct escarpment. Between Tites Point and Berkeley Road Station this physical feature is not pronounced, but becomes gradually more prominent to the south of the Junction.

The old question of the proper interpretation of these names, which was raised by Professors Nikitin and Pavlov, after their visit to this country for the Geological Congress in 1888 to whom no reply was made, for their conclusions could scarcely be denied, has been raised again by Miss Healy in a communication to the Quart. Journ. Geol. Soc., Feb. 1904. As these conclusions do not appear to be well known, it may be as well to quote them. Nikitin says: “Having found in the British Museum the original of Am. biplex, Sow. (tab. 293, fig. 1), I assured myself that that original presented absolutely the Oxfordian form of Perisphinctes of the group of P. plieatilis, by the character of its numerous straight rounded ribs, by the mode of enrolment, by the constriction of its perfectly visible whorls, and lastly by the matrix; it showed no resemblance to the Kimmeridgian and Portlandian forms described in France and England under this name… Mr. Loriol had not seen the original of Sowerby… but having received from England, under the name of A. biplex, Sow., the Portlandian forms, he was justified in giving this name to the same form from Boulogne. On studying the English Kimmeridgian forms placed in the museums of England under the name of A. biplex I found amongst them the typical form of A. Pallasi, D'Orb.’

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.

Through the great kindness of Professor Suess I have received the full text of his paper on Hot Springs, read before the Congress of Naturforscher und Aerzte held last year in Karlsbad, in which he adduces very strong arguments in favour of their being due to vapours given off from the molten interior of the earth as it gradually cools. I have for a long time been observing the hot springs that occur in the Cape Colony, and had come to the conclusion that they were surface-waters that had sunk deep into the earth's crust, and were returned heated in consequence of their having been in the neighbourhood of potential fusion of the rocks. This latter view I alluded to in a recent paper, and I do not like to have to give up a long-cherished idea before submitting to the public a statement of the reasons that led me to my view of the subject.

On hearing that Mr. G. E. Dibley, F.G.S., had exhibited at the June meeting of the Geologists' Association some test-plates of Marsupites from the Chalk of a new road near Russell Hill, I made inquiries of him, and he most kindly told me the particular locality where he and others had obtained these fossils. As the place was within an easy walk of my home, I visited it, in company with the younger members of my family, on an evening in June, and found, as Mr. Dibley had told me, that the greater part of the Chalk had been refilled into the sewer-trench, and the residue had been spread over the roadway and was now partly trodden down by the traffic. We patiently broke a number of the remaining blocks of chalk, and, in spite of the fact that Mr. Dibley had already carefully worked at the place, succeeded in finding not only a couple of plates of Marsupites with Echinocorys scutatus, etc., but also some smaller inconspicuous plates which, when cleaned from the matrix, proved to be test-plates of the unstalked, free-swimming crinoid, Uintacrinus, Grinnell. These showed the existence at this place of the lower portion of the Marsupites-zone, which has been designated by Dr. Rowe the “Band of Uintacrinus.”

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.

According to Professor Blanford the only example of this species in the Straehey Collection was the fragment which he figured. This is now in the British Museum collection [No. C. 5045]; it was transferred from the Museum of Practical Geology, labelled with one of that Museum's labels “Oolitic: Niti Pass. Ammonites scriptus (Stra.). Coll. by Col. Strachey.” The figures, which are all reversed, are not good. The portion of the fossil that is figured is entirely septate; the anterior part of the specimen that formed the base of the body-chamber is not included in the figure, nor does the figure show the shorter intermediate ribs which extend over the outer half of the lateral area of the whorl.

Mr. Alexander Somervail has been so good as to send me lately a paper read by him before Section C of the British Association at Southport, September, 1903, and printed in the Geological Magazine, Dec. IV, Vol. X, No. 472, October, 1903. The paper contains certain criticisms on the published work of Professor Hull, F.R.S., and myself among the Bed Rocks of the South Devon coast, with especial reference to “ the Base of the Keuper iu South Devon.” I desire to reply here to Mr. Somervail, and in so doing shall have to refer frequently to the three papers of my own published in the Quarterly Journal of the Geological Society in the years 1888, 1892, 1893, and to the paper by Professor Hull in the same Journal in the year 1892. For the sake of convenience and brevity I will refer to these papers by certain letters, as below.