Non-marine Bivalves Research Articles

XI.— The Upper Carboniferous Rocks of Arran

The Upper Carboniferous rocks of Arran are confined to a few small scattered exposures. Although these have been adequately mapped by Gunn,1 no detailed correlation of the various sections with each other or with the sequence recognised in the Midland Valley has yet been attempted. 1. Distribution. The best exposures are seen at the following localities:— 1. Corrie foreshore. 2. Locherim Burn, Corrie. 3. Merkland Burn, to the north of Brodick Castle. 4. Benlister Burn, west of Lamlash. 5. Headstreams of the Sliddery Water. 6. North-east coast, south of the Cock of Arran. (1) Corrie Foreshore. Here Upper Carboniferous rocks occupy the bay in front of the new Post Office, south of the Hotel. The succession is shown in tabular form below:— Gunn (1903, p. 41 and 1928, p. 66) classed the beds in this bay with the Coal Measures, as they contained organic remains (plants and non-marine lamellibranchs) of Upper Carboniferous facies, but added that “they and the equivalent beds elsewhere may possibly be Millstone Grit.” The faunal evidence obtained by the present writer is sufficient, however, not only to confirm the Coal Measures age of the sediments but also to establish the zonal position of at least the upper part of the succession. ‘Mussels’ have been collected from three bands, roughly 25, 35, and 60 feet respectively below the junction with the New Red Sandstone. The lowest of these has yielded Carbonicola os-lancis Wright (Fig. 1, c, d) and C. cf. rhomboidalis Hind, and, although lithogically it bears no resemblance to the Kiltongue Musselband This 250-word extract was created in the absence of an abstract The writer wishes to make the following acknowledgments: to Professor A. E. Trueman, Dr. J. Weir, Dr. G. W. Tyrrell and Mr. B. H. Barrett, for helpful advice and criticism; to the Geological Survey for the loan of palaeontological material; and to the Council of the Edinburgh Geological Society for a grant from the Clough Research Fund towards meeting expenses in the field.

XVI.— Naiadites from the Lower Carboniferous of Scotland : a Variation Study

The following is the first of a series of detailed variation studies of the non-marine lamellibranchs of the Lower Carboniferous of Scotland. Most of the forms have already been described by R. Etheridge, Jun. (1878), Hind (1894-5), and others. In the light, however, of more comprehensive methods in the revision of the Coal Measures species it has become essential to revise the Lower Carboniferous forms, and by statistics and illustration to define the course of variation within each species. The Lower Carboniferous rocks of Scotland differ from those of much of Southern Britain in the occurrence of thick series of estuarine deposits (the Calciferous Sandstone Series and the Limestone Coal Group): the non-marine faunas which they yield are thus of particular importance in relation to these investigations. Naiadites obesa and N. tumida (both R. Etheridge, Jun.) are by far the most abundant forms in the Lower Carboniferous. N. obesa occurs in great numbers on several horizons in the Calciferous Sandstone Series, while N. tumida is confined to the Limestone Coal Group. They are considered together, because, although Etheridge described them as separate species, Hind considered that he was dealing with one species, N. obesa. The writer agrees that they are closely related and in fact belong to one species-group, but considers that Hind's statement that Etheridge's descriptions offer no real point of distinction cannot be accepted, for the two types are easily distinguished and the distinguishing characters are stated in Etheridge's descriptions. In the following descriptions the conventional directions of This 250-word extract was created in the absence of an abstract The writer wishes to thank Professor D. I. Innes and Dr. G. A. Cumming of St. Andrews University for assistance in the field, and Professor A. E. Trueman, F.R.S. and Dr. J. Weir for advice and criticism. Thanks are also due to the Geological Survey for the loan of specimens. It should be recorded that the work was begun during the tenure of a Carnegie Teaching Fellowship in the University of Glasgow.

The Lamellibranch Zones of the South Staffordshire Coalfield

Scarcely any information has been published regarding the palaeontological sequence in the Coal Measures of South Staffordshire. Some marine bands have been recorded (summarized in Whitehead, 1927, p. 31) and there are isolated records of non-marine lamellibranchs, including a number which were figured by Wheelton Hind (1894–6). Practically nothing is known, however, concerning the zonal succession of either the shells or plants in that area. Recently, through the kindness of Dr. C. J. Stubblefield, the writer has had an opportunity to study a small collection of shells obtained in South Staffordshire by the late H. W. Hughes and now in the Museum of the Geological Survey. The specimens have been collected from known horizons and have proved to be sufficient to enable the writer to fix zonal boundaries and thus to make some suggestions regarding the correlation of the marine horizons.

A BOREHOLE SECTION IN THE CARBONIFEROUS AT FAIRWEATHER GREEN, BRADFORD

During 1939 and 1940 a boring for water was put down by Messrs. T. Matthews & Co. Ltd. at Sydney Works (Messrs. Illingworth, Wood & Co. Ltd.), Fairweather Green, Bradford. The boring was sited 467 yds. W. 43°S. of O.S. Bench Mark 461 ft., at Four Lane Ends, Bradford at about 445 ft. O.D. Percussion drilling was employed to 50 ft. The boring started in the Lower Coal Measures near the base of the Elland Flags and was continued to a depth of 1244 ft. 6 ins., ending in the Middle Grit Group of the Millstone Grit. Only specimens of the flagstones and sandstones were seen down to 505 ft. but below that depth the core was completely examined. The thanks of the authors are due to Mr. J. W. Adams of Woolcombers Ltd., who granted every facility for the examination of the cores and who also gave permission for the publication of the results and to Mr. D. Rumble of Messrs. Matthews & Co. who placed the borers’ log at the disposal of the authors. Professor A. E. Trueman named the non-marine lamellibranchs and to him especially the authors record their grateful thanks. SECTION OF BOREHOLE AT SYDNEY WORKS, FAIRWEATHER GREEN, BRADFORD. | | | | | | Thickness | Depth | |:------------------------ | --------------- | -- | -- | -- | --------- | ----- | --- | | | | | | | ft. | in. | ft. | in. | | | Made ground | .. | .. | .. | 4 | | 4 | | | Drift{ | Brown clay | | .. | .. | 6 | | 10 | | | Fine-grained bedded sand | .. | .. | .. | 1 | | 11 | | | Boulder Clay | .. | .. | .. | 1 | | 12 | | | | Shaly flagstone | .. | .. | | | | | |

A BORING IN THE LOWER COAL MEASURES AND MILLSTONE GRIT AT BRADFORD

The site of the boring is the works of the Sandoz Chemical Company Ltd. at Canal Road, Bradford, at about 205 ft. O.D. Drilling was carried out in 1938 and early 1939. Percussion drilling was employed to a depth of 42 ft. The core was examined at Easter, 1939. The boring was started in the measures near the base of the Elland Flags and, passing through the Lower Coal Measures to a depth of 356 ft., it was continued through Millstone Grit into the Guiseley Grit at a depth of 715 ft. The main interest in the strata passed through is the occurrence in the Lower Coal Measures of several horizons with Carbonicola faunas and the occurrence in the measures between the Rough Rock Flags and the Guiseley Grit of the various well-known marine bands with faunas which differ in some respects from those previously recorded from these horizons. The authors were granted every facility to examine the cores by Mr. J. E. Hills of C. Isler and Co. Ltd. and the Sandoz Chemical Company who have also given permission for the publication of the details of the bore. Professor A. E. Trueman named most of the non-marine lamellibranchs and Mr. W. S. Bisat gave considerable assistance with the naming of the goniatites. To both, the authors record their grateful thanks. BORING AT SANDOZ CHEMICAL WORKS, CANAL ROAD, BRADFORD. | | | Thickness | Depth | |:------------------------ | ------------------------ | --------- | ----- | --- | | | | ft. | in. | ft. | in. | | | Made Ground | 2 | | 2 | | | Subsoil and Boulder Clay | Stony clay with boulders | 22 | | | |

Prof. A. E. Trueman

THE chair of geology in the University of Glasgow, rendered vacant through the resignation of Prof. E. B. Bailey on his appointment as director of the Geological Survey of Great Britain, is to be filled by Prof. A. E. Trueman of the University of Bristol. Prof. Trueman was educated at High Pavement School and University College, Nottingham, and he received the degree of D.Sc. in geology from the University of London in 1918. He was appointed assistant lecturer in geology at Cardiff in 1917, and head of the Department of Geology in University College, Swansea, in 1920. In 1933 he succeeded Prof. S. H. Reynolds as Chaning Wills professor of geology in the University of Bristol. Prof. Trueman is best known by his researches in problems of Coal Measures Geology. In particular, he has taken an important part in the zoning of the Coal Measures of South Wales by means of non-marine lamelli-branchs, and in their correlation with other areas. He has also co-operated in research work carried out on dust from coal mines, in connexion with its bearing on the problem of silicosis among miners. In addition to his purely scientific work, Prof. Trueman has interested himself especially in the Workers Educational Association and other university extension activities. He is also a member of a committee appointed at Blackpool last year by Section C of the British Association to study the position of geology in the present educational system.

The non-Marine Lamellibranchs of the North Wales Coalfield

In the recent correlation of the Upper Carboniferous of England and Wales published by Professor A. E. Trueman (1933) the most obvious omission was a consideration of the North Wales coalfield. At that time, indeed, only three lamellibranch species had been reported from the area. In the present paper knowledge of the fauna is extended and the modern zonal scheme is applied to the coalfield. The floral zones recently introduced by Dr. E. Dix (1934) can be partially distinguished in the area, but these form the subject of a separate paper (Wood 1936b). The results are in accord with those based on the lamellibranchs. The area dealt with is shown on the map (Fig. 1), while the relationship of the lamellibranch zones and the coal-seams can be seen from Fig. 8. The Geological Survey memoirs dealing with the coalfield (Wedd & King 1924; Wedd & others 1923, 1927) contain little account of the fauna of the Coal Measures. The shell Carbonicola robusta (J. de C. Sowerby) (sic) was recorded from above the Main Coal at Mancot, near Hawarden, and was considered to indicate the Lower Coal Measure age of this seam. Anthracomya calcifera Hind was collected from the Upper Coal Measures to the south of Ruabon, while this shell and A. phillipsi (Williamson) were found in the Upper Coal Measures south of the Dee, outside the limits of the area dealt with in this paper. No other records were published, and shells were stated to be rare in the Coal Measures

XV.—The Basal Fauna of the Zone of Anthracomya modiolaris in the Coal Measures of South Ayrshire

In a recent paper on ‘The Zonal Distribution of the Non-marine Lamellibranchs in the Coal Measures of Scotland,’ Weir and Leitch (1936, pp. 725-726) were unable to record in South Ayrshire the musselband fauna which marks the base of the modiolaris zone in North Ayrshire and the Central Coalfield. The base of the zone was therefore taken provisionally at the Low Camlarg Coal (Fig. 1), following the final occurrence of Carbonicola pseudorobusta in the Beoch Musselband. The lowest modiolaris -fauna, studied by these authors in South Ayrshire was obtained from the roof of the Pennyvenie Two Foot Three Inch Coal which lies 170 ft. above the Beoch Musselband. The dominance of C. aquilina in this fauna suggests a fairly high horizon in the zone. Since the publication of the above paper two significant mussel horizons have been discovered in Auldnaw Glen, 4 miles N.E. of Dalmellington, South Ayrshire (six-inch Sheet 47 N.W.). The lower occurs between the Low Camlarg Coal and the Beoch Musselband and has already been recorded in a bore by the Geological Survey ( see Vertical Sections of the Scottish Coalfields, Sheet 20, 1932, Section 12). The upper horizon is a new record and occurs 24 ft. above the Low Camlarg Coal. These two faunas mark the sudden termination of the Carbonicola pseudorobusia sub-zone and the incoming of Anthracomyae related to A. modiolaris, C. os-lancis and Naiadites of the producta-triangularis group. We may therefore definitely place the lower boundary of the modiolaris zone just below the lower of these This 250-word extract was created in the absence of an abstract

XIV.—The Carbonicola Fauna of the Midlothian Fifteen Foot Coal: a Study in Variation

The purpose of the following paper is to describe an assemblage of non-marine lamellibranchs found above the Fifteen Foot Coal, one of the lower seams of the Coal Measures in the Edinburgh district. Reference has already been made to this musselband (Weir and Leitch, 1936, pp. 731-732), but, owing to the great diversity of forms present, it was considered advisable to defer the detailed description to a separate paper when adequate illustration could be given. The specimens were collected from several localities in the Midlothian Coalfield, in all cases from above the Fifteen Foot Coal; the majority were collected from Newcraighall Colliery, Niddrie, where they occur in great numbers in blaes with ironstone nodules. Specimens have also been collected by H.M. Geological Survey from the Joppa shore, and from the outlier of Coal Measures at Port Seton Harbour, but these exposures have since been covered up. Most of the fossils are internal moulds, but in many specimens, notably those which resemble C. pseudorobusta Trueman, the shell has been preserved; in these cases the shelly matter is extremely thick, with deep growth furrows. The assemblage shows great variation and, on first examination, might be thought to include several species of Carbonicola and Anthracomya , some of them new, others resembling shells from higher horizons. When viewed as a whole, however, it can be seen that these widely varying forms have a definite relationship to each other, and that all of them can be linked by intergrades to a centre or focus of This 250-word extract was created in the absence of an abstract

Societies and Academies

EDINBURGH Royal Society, December 2. J. WEIR and D. LEITCH: Zonal distribution of the non-marine lamellibranchs in the coal measures of Scotland. All zones from ovalis to tennis are represented in the Scottish Coal Measures, although they cannot all be delimited. The Productive Coal Measures fall within the ovalis, modiolaris and lower similis-pulchra zones, and are therefore homotaxially equivalent to the lower part of the Middle Coal Measures of Lancashire. In the Central Coalfield the boundary between ovalis and modiolaris zones is taken at the Kiltongue Musselband, and between modiolaris and similis-pulchra zones at the Musselband Coal. Correlations between Central, Douglas and Ayrshire coalfields are deduced. S. CHAPMAN: The lunar atmospheric tide at Glasgow. Reasons are given for believing that the lunar hourly inequalities of barometric pressure at Glasgow recently determined by Robb and Tannahill are substantially not of lunar origin at all (see NATURE, Nov. 16, p. 801). An earlier determination of the lunar atmospheric tide at Glasgow made in 1926 by Robb is now published with his permission, and appears to be a true lunar effect. It indicates that at Glasgow the lunar atmospheric tide is abnormally small for the latitude; the phase seems normal, and corresponds to a lag of high tide in the atmosphere of about one hour after lunar transit. ENID CHARLES: The effect of present trends in fertility and mortality upon the future population of Scotland and upon its age composition. Excluding the effects of migration, estimates of the population of Scotland during the next hundred years have been made on two assumptions, (a) that fertility and mortality remain at their present level, and (6) that they continue to decline at the rate shown in the past decade. According to (a), the population will begin to decline slowly about 1970, being 94 per cent of its present size in a hundred years. According to (6) the population will begin to decline about 1950 and thereafter will diminish rapidly, being 19 per cent of its present size in a hundred years. The effects of past declining fertility and of present low fertility will be seen in a continually decreasing proportion of children and increasing proportion of persons aged sixty years and more. The excess of females due to war losses will be replaced by an excess of males in 1960 by both estimates. In fifty years the increasing proportion of the older age groups will result in a higher crude death rate, between 18 and 21 per thousand. A. C. AITKEN and H. T. GONIN: Fourfold sampling with and without replacement. The correlation is examined of characters in a sample drawn at random from a limited population, the individuals of which are classed in four categories, as possessing two characters or their alternatives. In the cases both of replacement and of non-replacement of sampled individuals, the probability is found to be expressible as a terminating series in orthogonal polynomials. These are briefly studied, and applications are made to problems of regression and moments.

The Flora of the Upper Portion of the Coal Measures of North Staffordshire

The stratigraphy of the Coal Measures of North Staffordshire is, perhaps, better known than that of any other coalfield in this country. This is undoubtedly due to the detailed work carried out by pioneer workers such as Wheelton Hind, John Ward and Mr. J. T. Stobbs, and also to the fact that this coalfield offers remarkable facilities for the study of the various horizons in the Coal Measure sequence. The upper portion of the Middle Coal Measures and the lower part of the Upper Coal Measures, in particular, are (owing to the economic value of the pottery clays and the Black Band Ironstones) admirably exposed in quarries and excavations. These sections give an almost complete succession from the Ash Coal to the Keele Series. The present paper deals with the distribution of plants in the Coal Measures above the horizon of the Ash Coal. Most of the species here recorded were collected in the course of investigations chiefly concerned with the non-marine lamellibranchs in those measures, and undertaken while I was acting as research assistant to Prof. A. E. Trueman. A grant in aid of this work was received from the Department of Scientific and Industrial Research. I desire to acknowledge the assistance which has been given by all owners and officials of mines and marl pits in North Staffordshire. They not only allowed access to sections, but also gave facilities for collecting both above and below ground. As a result, the original records given in this paper refer to

Some Non-Marine Lamellibranchs from the Upper Part of the Coal Measures

The present paper deals with those non-marine shells which occur in the upper part of the Coal Measures: namely, in the Phillipsi and Tenuis Zones and in the higher portion of the Pulchra Zone. Those studies of the non-marine Lamellibranchs of the Coal Measures which have recently been published, have been directed chiefly to shells from the lower portion of the Coal Measures (Davies & Trueman, 1927; Wright, 1929; Clift & Trueman, 1929; and Hopkins, 1928, 1929). The shells which occur in the upper portion of the Coal Measures are mostly species of the genus Anthracomya, which have hitherto afforded evidence for no more than a broad classification of those measures; in the following pages we have attempted to define with greater precision the characters and ranges of these species. These investigations have been carried out with the assistance of grants from the Department of Scientific and Industrial Research, and we are particularly grateful for the generous way in which the Council of that Department has supported the work. One of us (A. E. T.) also wishes to acknowledge a grant from the Royal Society, which has defrayed certain expenses incurred during the early stages of the investigation. Most of the material described in the paper we have ourselves collected, and we wish to express our indebtedness to mine-owners and others for the cordiality with which we have been assisted in the various coalfields where collecting has been done. We have also had the advantage, through the kindness of Dr.

The Zone of Anthracomya tenuis in the Somerset Coalfield

The paucity of animal remains in the Coal-measures of Somerset has been recognized for many years. More recently Dr. H. Bolton has described fossils from various horizons in the coalfield, but his records relate chiefly to insects and marine fossils, while non-marine Lamellibranchs appear to be unusually rare at most horizons. A number of species of non-marine Lamellibranchs have been recorded by various authors, but in view of the wide interpretation formerly given to the various species, many of these records cannot be used for zonal purposes.

The Sequence of Non-Marine Lamellibranchs in the Coal Measures of Nottinghamshire and Derbyshire

I. I ntroduction . This paper gives an account of the succession of the non-marine Lamellibranchs of the genera Carbonicola, Anthracomya , and Naiadites in the Coal Measures of the southern portion of the Nottinghamshire, Derbyshire, and Yorkshire Coalfield. Much collecting was done in the area by Mr. R. D. Vernon (1911), who compiled a valuable account of the non-marine fauna, including lists of the fossils collected at many horizons. Twenty species of Lamellibranchs were recorded, and it was shown that certain of them are somewhat restricted in vertical distribution. Further records were noted by Mr. A. R. Horwood (1912, p. 108). Later, the late Dr. L. Moysey (1913) summarized existing knowledge of the distribution of fossils in the Coal Measures of Nottinghamshire and Derbyshire; a full bibliography of the palæontology of the Coal Measures of the area was compiled by Dr. Moysey, and it is, therefore, unnecessary here to deal fully with the progress of investigation in the area. In the various memoirs of the Geological Survey dealing with portions of the area, the sequence of coal-seams and the geological structure of the coalfield are fully treated. In most of the memoirs some reference is also made to the non-marine Lamellibranchs and other fossils from the Coal Measures. Dr. Walcot Gibson (1908, pp. 99–102) drew attention to the distribution of such forms as Carbonicola robusta and Anthracomya phillipsii , and described the fauna associated with the, chief seams in South Derbyshire. Later, these records were extended over a wider area (Gibson, 1913, p.)

A Revision of the Non-Marine Lamellibranchs of the Coal Measures, and a Discussion of their Zonal Sequence

The present paper deals with those Coal Measure lamellibranchs that are referred to the genera Carbonicola, Anthracomya , and Naiadites . These genera are represented at many horizons in the Coal Measures of Western Europe; they are now generally regarded as being of estuarine or freshwater habit, and it may be considered as established that they are not ordinarily associated with any of the marine forms which are found at certain horizons in the Coal Measures. In this country the most important advances in the study of these shells resulted from the work of the late Dr. Wheelton Hind (1893, 1894–96, 1904), who systematized the classification, and demonstrated the utility of various species in correlating coal-seams and in zoning the Coal Measures, especially of Staffordshire. Wheelton Hind published a critical bibliography of these shells in 1894, and it is therefore unnecessary to repeat here the history of research before that date. Reference is incidentally made to subsequent publications in the following pages, but it may briefly be noted that, apart from notable contributions by the late John Ward (1905), Dr. H. Bolton (1911, 1915), and others, the use of these shells in the correlation of the Coal Measures has been neglected in this country until recent years. It has been suggested that, for various reasons, they are less reliable in zoning than the plants. Owing to the labours of Hind and Ward, the sequence of these mollusca has been better known in the North Staffordshire coalfield than in any other British coalfield;