The mass called Jebel Ahmar or the Red Mountain near Cairo, whose slopes consist of an immense accumulation of quarry rubbish, is composed of hard brown, reddish and white sandstone and siliceous conglomerate. In many parts it has the characters of a perfect quartzite, and appears at first sight extremely unlike a member of the Tertiary series, newer than the comparatively soft and unaltered Eocene beds on which it rests, apparently in a conformable manner, though its dip to the N.E. is somewhat irregular, and apparently affected by false bedding. The induration of the beds seems to be local, and to be connected with certain fumarole-like openings which have probably been outlets of geysers or hot siliceous springs, contemporaneous with the deposition of the sand. Zittel I believe first gave this explanation, which suggested itself to me before noticing it in his memoir.

The group of shells figured on Plate VIII. (excepting Fig. 12, whose position is doubtful) constitute a natural section of turbinate or trochiform species, which should be classed under one and the same genus, or at most only separated subgenerically. They are characterized, for the most part, by a conical spire, having a rather wide angle; are few whorled, separated by a widish suture, and imperforate. The sculpture is rich, consisting of spiral bands of more or less prominence, which sometimes constitute varices, single or double, as the case may be. These spiral bands are usually granulated or tuberculated, and are continued into the base of the shell, which is convex and much produced. Between these spiral bands is a fine system of axial (radial) lines or striæ, sometimes bifid, and probably forming crenulations in connection with the more prominent spiral ornaments.

We are now in a position to indicate the succession of geological events in Egypt, and to compare them with those of neigh-bouring regions.

As in the case of Nerinœa, so also in this genus, we are dealing with its earliest representatives in so far as this district is concerned, since Tate and Blake make no mention of the occurrence of Alaria in the Yorkshire Lias. Piette, who accepts with modification Morris and Lycett's genus for this section of the winged shells, is of opinion that no truly winged shell has ever been found in the Lower Lias of France, though he describes species from the Middle and Upper Lias, none of which, according to his views, pass upwards. It was in the Lower Oolites that the genus Alaria first began to flourish, and we find in most places that it became tolerably well represented as low down as the Inferior Oolite or Bajocian subdivision.

The subject of the identity of the great shell (or rather cast), which occurs in the Scarborough Limestone, with the Corallian P. striata, was partly discussed in the “Corallian Gasteropoda.” The considerable abundance of this form on certain horizons in the Oolites, both of the north and south of England, and its complete absence from other horizons, has attracted considerable attention. Thus it appears alike in the Humphresianus-zone of Scarborough and of Cheltenham, but not, as far as I know, in lower beds. The Yorkshire specimens are not good enough to warrant any conclusions as to the specific difference between this and the Corallian forms; therefore it seems safer to follow the authors of the Great Oolite Mollusca in referring the White Nab fossils to Sowerby's species. Moreover, I have less doubt as to the propriety of this course after reading the very interesting remarks of MM. Terquem and Jourdy with reference to Bourguetia striata.

It is well known that the slates of the Borrowdale series in the Lake District furnish beautiful illustrations of faulting on a small scale; but so far as I am aware, no description of them, from this point of view, has as yet appeared. The accompanying Plate has been produced in Autotype from one of these slates, the surface of which was first most carefully smoothed and afterwards varnished. Every detail of the faulting is shown in the most perfect manner, and the general tint of the slate is also reproduced. The specimen was purchased at the village of Rosthwaite in Borrowdale; but I was not able to learn the exact locality from which it was obtained. I have little doubt, however, that it came from the Honister quarries. Mr. De Rance tells me that similar slates occur at Tilberthwaite, near Coniston. The plate is of the natural size. The face represented is a cleavage plane, and neither the bedding nor the fault planes are at right angles to this face. The bedding planes make with it an angle of about 40°.

The remains of many genera and species of the Order Carnivora have been discovered in the Lower and Middle Tertiaries of the European Continent, and have been described and figured in numerous valuable palæontological works and memoirs by Continental authors. That these remains are exceedingly rare in the older Tertiaries of England is proved by the fact, that only one Carnivore, the Hyœnodon, has been placed on record as occurring in them.

This widely-spread, and, on the whole, well-marked species, has been in so many cases, as it appears to me, confounded with Alaria bispinosa, that it would be a task of no small difficulty to trace out the mistakes that have arisen in consequence. The imperfect figures of Phillips have, no doubt, been the principal cause of thus confounding the two species. Deslongchamps queried the identification, but yet was inclined to adopt it. Morris and Lycett seem to have had no doubt on the subject. “Having had the advantage of examining a large number of specimens, comprising every variety both in form and stage of growth, we feel no hesitation in uniting the two species here indicated.” It is extremely probable that the Great Oolite specimens of Alaria trifida present varietal differences from the Oxfordian types, and they may also in some cases have assumed forms having only one lateral digitation; but higher up in the Jurassic rocks they seem to be very fairly separable for such a genus as Alaria, which is so prone to effect changes in its shell. Such was doubtless the opinion of Morris, who quotes Al. bispinosa from the Lower Calc. Grit and Kel. Rock, whilst Al. trifida is quoted as a distinct species from the Oxford Clay and Kel. Rock of Yorkshire, the Great Oolite form being referred to a variety.

Nearly ten years ago it was my privilege to describe the British Cretaceous forms of this Family in the Geological Magazine. The Family was seen to be capable of subdivision into at least five well-marked genera, and to these a sixth very singular and remarkable one from Aix-la-Chapelle, and also represented at Blackdown, may be added. It was then that the Family reached its zenith, and in the still later Cretaceous rocks of Europe, as a flame burns brightest near its end, so some species suddenly assumed relatively gigantic proportions, and as suddenly became extinct. A few survived in America down to that much later period, the close of the so-called Cretaceous series on that continent. Only two types lived on to the present day and only one of these has ever since Cretaceous times been represented in our area.

The Rev. A. Irving, in the January Number of the Geological Magazine, p. 46, writes: “The argument then in favour of the retention of the name ‘Permian’ (as against e.g. that of ‘Dyas’) is based on no logical consistency with established geological nomenclature. It is an excellent local name for the Russian series, but as a general term for the European series it is highly misleading.”

I Am indebted to R. L. Jack, Esq., F.G.S., the Government Geologist of North Queensland, for permission to examine the remains of a Neuropterous wing (figured on Plate XI. Fig. 1), and which forms one of a collection of Cretaceous fossils transmitted by him to my colleague Mr. Robert Etheridge, jun., for description.

Shortly after my arrival in Cairo, Dr. Schweinfurth, of that city, was so kind as to conduct me to a remarkable sea-terrace at the foot of the Mokattam hill, behind the tombs of the Caliphs, and stated, on the authority of Col. Ardagb, R.E., to be at an elevation of about 200 feet above the level of the sea, and which, I believe, was first described by Oscar Fraas. At this place a cliff of hard Eocene limestone, about 30 feet in height, has been perforated by Lithodomi, whose burrows are now filled with a grey calcareous deposit, and valves of a small species of oyster are also attached to the surface of the rock. The burrows resemble those of an ordinary Mediterranean species of Lithodomus, but I did not see the shells. The oyster has been described by Fuchs as a new species, under the name O. pseudo-cucullata; but, according to Dr. Schweinfurth, it does not seem distinguishable, except as a variety, from O. cucullata, Born. (=O. Forskali, Chemn.), of the Red Sea. Since the locality was observed by Fraas, Dr. Schweinfurth has discovered other shells in the crevices of the rock, more especially a Pecten, a Terebratula, and a Balanus, all modern species. The recent character of these shells and their mode of occurrence and state of preservation, oblige us, I think, to assign them to the Pleistocene, or at farthest the later Pliocene period, though I am aware that they have been regarded as Miocene.

Since the appearance of my paper in the Geological Magazine, 1883, Decade II. Vol. X. pp. 534–542, the following species have been added to the list of British Carboniferous Limestone Trilobites, and will form a part of the forthcoming volume of the Palæontographical Society for the present year.

A Sudden and great change takes place in the geology of the Nile valley in approaching the First Cataract, where we pass from the unaltered and nearly flat Nubian sandstones to rocks highly crystalline, greatly disturbed, and penetrated with multitudes of igneous veins.

In 1863 Professor James Hall described and figured three abdominal segments, with the telson and its appendages, of a Ceratiocaridal Crustacean, characterized by its relatively large size (about 100 mm. long, and from 10 to 15 broad) and by the presence of strong spines on the distal upper edge of each segment [see annexed Plate, Fig. 2]. This form, from the shales of the Hamilton group (Devonian) of Ontario County, N.Y., he referred with doubt to Ceratiocaris, and gave it the specific name “armatus.” At the same time Prof. Hall described and figured some separate caudal spines, from the Genessee Slate, Ontario Co., as C. ? longicaudus, of which his figs. 4, 5 and 6 may be the same as those of C. ? armatus; whilst fig. 7 seems to be two small body-segements and caudal spines of some other Phyllopod. To these Prof. Hall added, in the same plate, the figure of a relatively large Leperditioid carapacevalve, doubtfully referred to Ceratiocaris as C. ? punctatus, from the Hamilton Group, east shore of Cayuga Lake, N.Y.

The Sauropoda are now generally recognized by anatomists as a well-marked order of the Sub-class Dinosauria. In the previous articles of this series, the main characters of the two families of this order (Atlantosauridæ and Morosauridæ) already named by the writer have been given.3 A third family is represented by the genus Diplodocus, a study of which, more especially of the skull, throws light on the whole group of Dinosaurian reptiles.

The molluscan fossils figured on Plate XI. were transmitted to the Editor by Mr. Hy. Y. Lyell Brown, F.G.S., Government Geologist for South Australia. They are from two localities in that Colony, one near Mount Hamilton, 20 miles S.W. of Lake Eyre, but the greater part came from 40 S.W. of the Peak. There is nothing in the collection which could be quoted as absolutely decisive of their age, though we may fairly regard them as Mesozoic. The conditions of fossilization remind us of the Jurassic fossils of this country, and the general facies is not dissimilar. But these resemblances should not be taken for more than they are worth, the more so since we fail to trace absolute specific identity.

The following propositions respecting faults apply to strata, which are either horizontal, or which have a uniform dip. If they have a uniform dip, the country, faults and all, may be supposed turned back through the angle of dip, and the strata will become again horizontal. We need then only think of horizontal strata, if we bear in mind that “horizontal” and “vertical” really mean only, parallel and perpendicular to the bedding. This artifice will simplify the subject; but it does not imply that the faulting took place before the beds were tilted, which may, or may not, have been the case.

Several trochiform shells found in the Jurassic rocks, which were formerly referred either to Trochus or to Solarium, have in more recent years been regarded as related to the genus Onustus. I am not aware who was the first author to adopt this view, but we find Hébert and Deslongchamps (1860) recognizing the genus in the Callovian of Montrueil Bellay. Subsequently Lycett (Suppl. to the Great Ool. Moll. p. 103) gave a diagnosis, more especially as applicable to the Jurassic species, and described Onustus Burtonensis from the Forest Marble of Burton Bradstock.

I Have recently obtained from the Borough Lee Ironstone several specimens of a Selachian spine, apparently new, and showing several features of a very interesting character.