Ralph Tate

On some Secondary Fossils from South Africa

I. Introduction As a large number of fossils from the Secondary rocks of South Africa remain undescribed in the Societys Museum, it seems desirable that an account of them should be submitted to the Society, as a sequel to the Monographs on Secondary Fossils from South Africa which have appeared in the Societys Transactions and Quarterly Journal. This paper contains descriptions of the Plants of the Karoo beds, the Reptilian and Molluscan life of which has been made known by the labours of Professors Owen and Huxley, and the late Mr. Daniel Sharpe—of the vegetable remains from the phytiferous beds of Geelhoutboom, and of the fossils from the Jurassic strata of the Zwartkop and Sundays River (the last part being a Supplement to Mr. Daniel Sharpes “Descriptions of Fossils from the Secondary Rocks of South Africa”). The study of the organic remains of the beds enumerated has enabled me to offer, in addition, some generalizations on the affinities of each of the above-mentioned groups of Secondary strata developed in this region. II. Karoo Beds a. Fossil Flora of the Karoo Beds. 1. Glossopteris Browniana, Pl. VI. figs. 5a, 5b, 7a, 7b. The Society is in possession of several impressions of a Glossopteris, in a friable sandstone, obtained by Dr. W.G. Atherstone, F.G.S., from Heald Town, near Fort Beaufort, Eastern Province, South Africa,—and many others of the same form, in a dark shale, from Bloemkop*, collected by Mr. C. J. Powell, of Graaf Reinet, and presented by Dr. R. N. Rubidge,

On the Correlation of the Cretaceous Formations of the North-east of Ireland

In a former communication I described “The Rhætic and Lower Liassic Rocks of the neighbourhood of Belfast”*, and I now propose to continue the subject with a description of the strata which surmount the Liassic series, namely, the Upper Cretaceous rocks in part. An incentive to study these formations was the knowledge that the results of the labours of the late Robert McAdam, Esq., F.G.S., had been anxiously looked for by many geologists†, who hoped that the true relationship of the Irish Cretaceous beds would have been satisfactorily determined by him from the study of his own collection of local fossils. That geologist has passed away from amongst us without having accomplished these researches; and as his collection has not been applied to the furtherance of the much-desired object up to the present time, I have undertaken the task he may have intended to perform. During a residence of two years and a half in Belfast, I have worked assiduously in collecting fossils from the Irish Cretaceous strata, and in studying their lithology and stratigraphical characters, with the hope that these materials would enable me to correlate them satisfactorily; and I shall now endeavour to show that they belong to the so-called Upper Greensand and to the Upper Chalk. The general features of the disposition of the Neozoic rocks in the neighbourhood of Belfast may be understood by reference to the accompanying section. II. Absent Formations. 1. Oolitic Strata.—In the foregoing section, the Cretaceous beds

On the Palæontology of the Junction Beds of the Lower and Middle Lias in Gloucestershire

Previous to the writings of Messrs. Oppel and Wright on the classification of the various members of the Lias, that portion of the system which intervenes between the great limestone series of the Lower Lias below and the Marlstone above was referred to the Lower Lias; but these authors have drawn the line of demarcation between the Lower and Middle Lias through the mass of clays and shales which constitute the median portion of that system, the zone of Ammonites raricostatus being the uppermost member of the Lower Lias, and that of Ammonites Jamesoni the lowermost member of the Middle Lias. Now it has not been shown in any English publication that this separation harmonizes with the distribution of organic remains, and by the superficial reader the boundary-line may well be considered an arbitrary one; it will be my endeavour to establish the division of the Lower and Middle Lias as drawn by Oppel. That the zone of Ammonites capricornius is intimately connected with the Marlstone there cannot be a doubt, and in the Yorkshire Lias it has for many years been grouped with it; but as the zones of Ammonites Jamesoni and A. ibex, in this country, have usually been regarded as imperfectly fossilfferous, the necessary data for comparison being absent, the position of these zones in the Middle Lias has, with some degree of reasonableness, been questioned, more especially because the lithologieal conditions of the upper zones of the Lower Lias (sensu stricto) are repeated in the zone

On the Lias about Radstock

A recent writer* states that the geological history of Somersetshire has yet to be written; if this be true (and it is not for me to decide), what a marvellous tale will have to be told! if we may judge from the deeply interesting portions of that history already made known to us by Mr. C. Moore, some of the results of whose labours, which cover many years, are embodied in two communications to this Society†, and are illustrated by a most extensive and exquisite suite of fossils deposited in the Bath Museum. Without seeking to disparage the larger views set forth in the last-mentioned papers, yet I consider a modified interpretation of some of the phenomena is required; and calling to my aid an extended acquaintance with Liassic species and their distribution, I believe that I am in position to give a more complete account of the sequence of deposits, so far as relates to the Liassic rocks in the neighbourhood of Badstock, than has yet been done. Wherever the Lias has been critically studied, it is found that there is a parallelism in the succession of life, most especially in regard to the species of Ammonites—so much so that the strata admit of a grouping after their palæontological characteristics, and further into regions of Ammonites, a classification as much in harmony with facts as that of the Oolitic rocks into formations. The recognized divisions of the Lower and Middle Lias as follows:— Middle Lias. Zones of Ammonites spinatus

Appendix.-On the Palæontology of Skye and Raasay

I. Palæontology Horizons, Skye, &c., and Lists of Fossils. Rhætic? The conglomerates, quartzitic sandstones, and brick-red and greyish sandstones, forming the cliff Ru-na-Leac, may be of this age. No fossils observed. Lower Lias. Hettangian Series(=zones of Ammonites p1anorbis and A. angulatus).—The blue argillaceous limestones and indurated shales constituting the under cliff on the north side of Ru-na-Leac Bay, I regard as the basal portion of the Lower Lias. Beds 1 to 4, Geikies section, may probably belong here. The fossil evidence, however, is inconclusive, the coral being peculiar, and the other two species recorded from these beds occurring elsewhere in the zones of A. angulatus and A..Bucklandi, and even higher. A sandstone on the north slope of Ben Glamaig, yielded me impressions of Terquemia arietis, Quenst. Zone of Ammonites Bucklandi.-The rocks of this series present the characteristics of the Yorkshire type of the Lima or Bucklandi beds of the south of England, consisting chiefly of shales with shelly tops and thin earthy limestones, contrasting with the compact blue limestones of the underlying series. The section opposite exhibits the lithological variations of this horizon in the Waterfall Cliff, Hallaig, Raasay. Order ascending. The greyish and yellowish-coloured calciferous sandstones which form the remaining portion of the cliff, contain throughout scattered Gryphæa arcuata; no other fossils observed. I place here beds 5 to 11 of Geikies section, as a few characteristic fossils of this horizon were obtained from beds 5, 6, 8, and 10; they are given in the subjoined Table. The limestone

On the Age of the Nubian Sandstone

Mr. Bauerman, in a recent number of the Quarterly Journal of this Society (vol. xxv. p. 27), has discussed at some length the opinions advanced respecting the age of the sandstone strata underlying the Cretaceous limestones, and resting upon the granitic and schistose rocks, in Sinai. These rocks belong to the same series of sandstones described by Russegger as occurring in Egypt, Nubia, and Arabia Petræa, under the name of “Nubian Sandstone.” Though the facts that I have the honour to submit to the Society may be stated in a few words, yet it seems desirable to recapitulate briefly the views that have been advanced as to the period of deposition of the strata in question, the better to explain away those inferences which are so much at variance with my own. In the first place, it appears, from the circumstance of the Nubian Sandstone being overlain conformably by approximately horizontal strata of Cretaceous age, that this formation has been regarded, in the absence of palæontological evidence to the contrary, as forming part of the Mesozoic group of rocks. Thus Russegger colours and describes it as Lower Cretaceous in his maps ; and Bauerman, guided by the lithologieal similarity of its strata to the Lower New Red Sandstone about Chester, has placed it on the horizon of the Trias ; whilst Figari Bey seems to have regarded the tripartite arrangement and lithological features of the series as suflleient tests by which to assign the whole to the Trias, “taking the

Note on the Middle Lias in the North-east of Ireland

Portlock in his ‘Survey of Londonderry’ makes no mention of the presence of the Middle Lias in Ireland; and an examination of the species of fossils collected by him proves that no higher member of the Jurassic series than the Lower Lias is represented by them. In a former communication I demonstrated the presence of the whole series of the Lower Lias, and, till recently, was unaware of the occurrence of strata newer than that formation. Mr. William Gray has sent me several blocks of a grey, marly, micaceous sandstone, charged with organic remains of Middle Liassic age; these were obtained near the town of Ballintoy, “in fields and cultivated patches of drift,” and conjectured by the discoverer to have been derived from the immediate vicinity; but up to the present time they have not been referred to their parent site. With the exception of Plicatula spinosa, Avicula novemcostæ, and Rhynchonella variabilis, which range throughout the Lower and Middle Lias, the majority of the determined species indicate an horizon below the Marlstone but above the highest beds of the Lower Lias. The close similarity in lithological composition, and in part in fossiliferous contents, between the Pabba shales and the blocks found at Ballintoy suggests the probability of the latter having been transferred during glacial times from the Hebrides. Nevertheless the sandstone blocks from Ballintoy belong unquestionably to the Middle Lias, and appertain to the lower division, which includes the Jamesoni-bed, the Ibex-bed, and the Capricornus-bed, and are contemporaneous (if not.

On the Fossiliferous Development of the Zone of Ammonites angulatus, Schloth., in Great Britain

I. Introduction. The beds comprised between the Avicula-contorta series and the limestones of the zone of Ammonites Bucklandi vel bisulcatus have been divided into two lithological horizons, the lower of which, that of Ammonites planorbis, presents no marked zoological facies when contrasted with the upper, that of A. angulatus, which has a fauna exceeding in richness of species the remainder of the Lower Lias. The term “Infra-lias” has been given to this group of beds; but as its applicability varies with the classificatory views of individual authors, it seems, therefore, inadmissible; and, in my opinion, that of “Hettangian,” as suggested by Prof. Renevier†, should be used instead. The classification of the members of the Lias would then stand thus:— In England the Hettangian series contains a well-developed zone of Ammonites planorbis, whilst according to: Dr. Wright* “the zone of Ammonites angulatus, so far as it has been exposed, appears to be imperfectly developed in the British Isles; and from the difficulty experienced in separating its beds from the Bueklandi-series, they were grouped with the latter in my memoir.” This difficulty I have been enabled to overcome; and the determination of the zone of Ammonites angulatus with its characteristic fauna, in the localities hereafter to be mantioned, rests on lithological, stratigraphical, or palæontological evidence, or on a combination of two or all of these indices to the age of the horizon in question. II. Occurrences of the Zone of Ammonites angulatus. 1. Ireland—The development of this zone in the neighbourhoods of

On the Lower Lias of the North-east of Ireland

1. Introduction—From a more extended survey of the Liassic strata in the province of Ulster during the summer of 1866 than I had previously made, and from an examination of the fossils of the Lower Lias of that area, I am constrained to make some slight modifications of my views on the correlation of the members of the Lias of Ireland, as given in a paper entitled “The Liassic strata in the neighbourhood of Belfast,” published in the Quarterly Journal of this Society*. In that paper I pointed out the occurrence of beds of Rhætic age, embracing the Avicula-contorta shales and the White Lias, and of beds of the age of the Lower Lias, which I had regarded as equivalent to the zone of Ammonites Bucklandi of the English Liassic series. I have examined every exposure of the Lias in the north-east of Ireland, and have no reason to take exception to Sir Richard Griffiths mapping of this formation—that is, viewing the Rhætic series as a subfbrmation of the Lias. But the principal portion of the Lias belongs to the Avicula-contorta series, which is invariably the underlying stratum to the Lower Lias; however, on the shores of Lough Mourne and Larne Lough, and on the coast at Ballintoy and Portrush, the base of the Lower Lias is not seen. And although the shales of the Avicula-contorta series are usually covered by the Lower Lias, yet, on the other hand, they are the last to disappear in the thinning-out of the

On the Liassic Strata of the Neighbourhood of Belfast

General Portlock, in his Geological Report on Londonderry, Tyrone, and Fermanagh (1843), was the first to direct attention to certain beds linking the Triassic and Liassic formations. In that Report he refers to the occurrence of beds at Colin Glen, Belfast, characterized by the same Shell (Cardium striatulum) as that which occurs in the Lisnagrib section (pp. 49, 56, 107). It is now my purpose to describe in detail the strata thus referred to, and their extension to neighbouring localities. Within the last few years the stratigraphical relations and the fauna of the Lower Liassic and Avicula-contorta series, as developed in England, have been made known by the labours of Dr. Wright and Mr. Charles Moore.