CHAPTER XXIX. THE MALVERN AND ABBERLEY HILLS, AND THE LEDBURY DISTRICT. By THEODORE GROOM, M.A., D.Se., F.G.S., F.R.G.S. PART I. PHYSICAL FEATURES AND COMPONENT ROCKS. HE geographical centre of and Wales is the heart T of the English Midlands. This central area may be described as a relatively low-lying, undulating plain, from which, like islands, rise the more elevated tracts of South Staf­ fordshire, Warwickshire, Leicestershire, and Northamptonshire. The greater part of the plain is formed by gently rolling beds of Trias, but towards the south and east by the Lias. Here and there the plain is diversified by minor scarps and ridges formed by the more durable beds of the Lias and Trias. Its western boundary is the more elevated and hilly tract of the Welsh borderland, which comprises some of the higher parts of Shrop­ shire, , and Gloucestershire. The elevation of this tract is due, partly to the durability of the Palseozoic and Archrean rocks of which it is composed, and partly to upheaval. Much of its surface is occupied by the Old Red Sandstone, but along the eastern border, which runs nearly north and south, emerge the harder Lower Palaeozoic and Archeean rocks of May Hill, the Malverns, and the Abberley Hills. The scenery on the two sides of the Malvern-Abberley range differs appreciably. On the east lies the southern extension of the Midland plain, here narrow and bounded on the east by the Cotteswolds. Watered by the Severn, much of it forms pasture or arable land, dotted with villages and towns. The Malverns rise up abruptly from this plain in a manner suggestive of an ancient coast line. On the western side of the range is the hilly tract of the Old Red Sandstone, with its rich hop lands and orchards, and occasional park lands of fine oak. The population is appreciably less dense than to the east, and towns of even fair size are scarce. The strata are thrown into folds, which towards the Mal­ verns are much more marked than those of the Trias on the east. The Silurian cores of some of the more marked anticlines rise up to form the picturesque wooded heights of the Ledbury and Woolhope Hills. Viewing broadly the disposition of the strata between the Mal­ vern and Abberley Hills on the east, and the hills of Radnor­ shire and South Shropshire on the north-west, the area is seen to be formed by a syncline with a flat or gently undulating base THE MALVERN AND ABBERLEY HILLS. and more sharply recurved edges. In the lap of the syncline where denudation has been less effective stand the Clee Hills with their remnants of Carboniferous Limestone, Millstone Grit, and Coal Measures. The Malvern and Abberley Hills constitute a part of the eastern rim of this basin. The Malverns form a chain of heights extending from Chase on the south to North Hill; the highest summit is the Beacon. The county boundary between Herefordshire and Worcestershire follows the crest of the range. Continuing the line to the north is a chain of lower and less striking heights, to which the general name of Abberley Hills has been given. The formations represented in the two ranges and their im­ mediate neighbourhood are the following: Archsean, Cambrian, Ordovician (Tremadoc), Silurian, Old Red Sandstone, Car­ boniferous, "Permian" (Midland type), Trias, and Pleistocene. The Carboniferous is represented by certain Coal Measures alone, but at no great distance, in the Forest of Dean and in the Clee Hills, occur the Carboniferous Limestone and Millstone Grit. The Lias and Rhretic are also within easy reach. The outcrop of these formations in the Malvern district is indicated on the map (Plate XXIII, Fig. I). The sequence is interrupted by a number of unconformities, as shown in the following table:

PLEISTOCENE. Unconformity. JURASSIC Lias. ~~:; ~~ " Probable unconformity. TRIAS. Upper Bunter Sandstone. Probable unconformity. 1 Bunter Pebble Bed. Lower Bunter Sandstone. Probable unconformity. PERMIAN (?) Haffield Breccia. Unconformity. Coal Measures. CARBONIFEROUS. Unconformity . { Coal Measures. Unconformity, OLD RED SANDSTONE. Ledbury Beds. Downtonian.{Downton Sandstone. Upper Ludlow Shales. Aymestry Limestone. r ( Lower Ludlow Shales. SILURIAN. .\ Salopian, -Ii wenlo.Ck Limestone. Wenlock Shale. . Woolhope Limestone. . j Woolhope Shales. "ValentJan. 1 May Hill Sandstone. Unconformity, 700 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME.

ORDOVICIAN. Tremadoc. Bronsil Shales. (Uppe! White-leaved Oak Shales, CAMBRIAN. Middle. { Hollvbush Sandstone. i Lower. Malvern Quartzite. Probable unconformity. ARCH£AN. Malvernian and Warren House Series.

ARCHlEAN ROCKS. The Archaean rocks* are seen chiefly in the , the core and highest parts of which they form. Small patches are also found in Cowleigh Park and near Martley in the Abber­ ley Range. The rocks include two apparently distinct series:

2. Warren House Series. 1. Malvernian Series. No trace of a sedimentary series comparable with the Long­ myndian of Shropshire and May Hill has been detected. The M aluernian comprises a series of schists and gneisses in which hornblende, chlorite, white mica, felspar and quartz are the dominant minerals. Associated with these rocks are red binary granites, diorites of medium or fine grain, felsites, and occasionally other rocks, such as syenite and olivine diabase. The complex thus formed has not hitherto been mapped in detail, though the rocks are admirably exposed in many places, more particularly in the fine quarries near the northern end of the hills, and in the Hollvbush Pass. So extensive, indeed, has been the quarrying that permanent injury to the picturesqueness of the neighbourhood is feared. The Warren House Seriest (Fig. 120) is found only on the easternside of the , and in the neigh­ bouring part of Castlemorton Common. It is stated to consist of rhyolites, andesites, basalts and tuffs, but the assemblage awaits detailed description. The prevailing dip seems to be easterly, as though the series overlay the adjoining Malvernian. The junction not improbably dips in the same direction, but it is not clear that the two series are not separated by a fault. There can be little doubt that the Malvernian and Warren House Series are of pre-Cambrian Age. The chief considerations bearing on this question are the following: (I) Although the Cambrian can in no place be observed to rest directly on either, its general dip is away from them. (2) The very considerable metamorphism of these rocks, especially of the Malvernian, suggests an age much greater than that of the slightly altered Cambrian. (3) The rocks cannot be readily paralleled lithologically with any post-Archzean rocks in the country.

'~See List of Works on page 738. Nos. 3, 8-13, 16, 19,20,23.24. t List of Works, Nos. 9, II, 19,28. THE MALVE RN AND ABBE RLEY HILLS. 701

(4) The Malvern ian has much in common with the gneissic and schistose rocks of Shropshire believed to be pre-Cambrian, and the Warren H ouse rocks compare well with the Uriconian of the same countv. (5) The conglomeratic beds of the May Hill Sandstone and Mal vern Quartzite include rolled pebb les of alt ered rocks, some of which are very similar to the granites of the Malvernian, and others to the lavas of the Warren H ouse Series. This seems to imply great denudation and pa rtia l alteration of the old rocks before the depo sition of the Cambria n, and probably an un­ confo rmity at the base of the latter. (6) T he plagioclin al structure of the Mal vern s suggests great pre-Cambrian folding and denudation.

C AM BRI AN AND O RD OVICIAN ROCKS :*. The Cambrian consists of : 3. The White-leaved Oak Shales (" Black Shales "). 2. The H ollybush Sandstone. 1. The Malvern Quartzite. The Malvern Quartzite is commonly a grey quartzite of rather fine grain. It is seen only in shattered strips, chiefly towards the southern end of the Malvern s, but small exposures are visible in Cowleigh P ark, and at Martley in the Abberley Hills. T he total thickness may be several hun dreds of fee t. The best ex­ posures are at the northern end of in the Gull et P ass, and in Winter Combe on the Raggedstone. I n the locality first mentioned beds of conglomerate alternate with quartzite. The ground-mass of the conglomerate consists chiefly of grains of quart z, quartz-schist, rhyolite, orthoclase, microcline, plagio­ clase, white or green mica, chlorite, together with epidote, ilmenite, iron pyrites and glau conite. The pebbles are chiefly metamorphic quartzite or quartz-schist, plutonic quartz, rhyo­ lites, granite, orthoclase, microcline, plagioclase, chlorite-schist, and quartzose diorite ; less abundant are mica-schist, diorite, gneissic diorit e, andesite, basalt, sandstones, and clastic quartzite. Of these mat erials, some have evidently been derived fro m a complex resembling the Malvernian, and others from a volcanic series like the Uriconia n ; but a third group, largely repr esented, including such rocks as the quartz schists, are very poorly represented in the Mal vern Hills. The chief fossils foun d in the Quartzite are Kutorgina plzillipsii, Holl., Obolella (?) groomii, Matley, and H yolitllUs prim e-uus, Groom. The H ollybusli Sa nd stone (Fig. II6) is exposed towards the southern end only of the Malverns. In the la rge quarry at White-leaved Oak it ap pears to pass down into the Malvern * List of Works, No . 27. 702 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME.

Quartzite, but only one or two feet of the latter are visible. The Sandstone is prevailingly of a dark-green colour, due to the presence of numerous grains of glauconite, chiefly casts of for­ aminifera. The rock, in fact, is an old greensand. In addi­ tion to the more massive sandstones that appear to consti­ tute the bulk of the formation, grey or black sandstones and quartzites, and thin conglomeratic layers and impure limestone occur. The portion of the formation that appears to form the 1.1.---- base is more flaggy and shaly than the rest. Altogether the sandstone may be 1,000 feet thick, but its faulted condition, the difficulty of re­ cognising - definite horizons, and the insufficiency of the exposures, make an estimate difficul t. u,til Lithologically the o <'i Hollybush Sandstone u -<: closely resembles the z c5 11 Comley Sandstone of o E=: § II Shropshire, and it is u in rJJ to be hoped that the <>l 'O~ rJJ 1'1 I gs. @'u: succession now being \Ci ~ ~ rJJ § worked out there bv M M .8 E5 :;:: dQ Prof. Lapworth and 't:l .; .::r1 1U Mr. Cobbold will 8 .:g"g .:a.~ ~ g; throw much light on ~ ~ t1l~b~~ that in the Malvern ~ -' area. The best ex- ~ :i to ~ __ ~ .~ ~~~~~~~ :r:te ~~ ~~~ Raggedstone and Midsummer Hill. The prevailing constituents of the sandstone, including the conglomeratic layers, are quartz, metamorphic quartzite, and quartz-schist j glau- THE M AL VERN AND ABBERLEY HILLS. 7° 3 conite; orthoclase ; white or green mica ; plagioclase ; sphene and opacite; rhy olite ; calcite ; derived epidote; microcline, brown mica . The materials are usuall y more or less water-worn, and are such as might be largely derived by denudation of an old series of rocks including granite, metamorphic quartzite, quartz­ schists, and rhyolites. The chief fossils are Kutorgina plzillipsii, H oll. , H yolitlzu s fist ula, H oll., H. primaous, Groom, H. mal­ uernen sis, Groom ; but these are rare, and have been found in a fe w local ities only. The W lzi te-l~ a ved Oak S hales (Fig. II6) are exposed only on the western side of the Malverns, south of the Gullet Pass ; but they have been reached in a well sunk on the western side of Nor th H ill. They are soft, fine-grained, very fissile sha les, black in colour where not bleached by intru sive rocks. Apart from an included series of basalts, they are probably over 500 ft. thick. The lowest, 30 ft. or so, are di stinguished by the presence of thin bands of rather coarse black glauconitic grit, the shales associated with which contain an ab undance of the small ostracod P olyplzyma lap wortlzi, Groom, toge ther with Protosp ongia [enestrata, Salter, Acrotreta maluerncn sis , Mat ­ ley, Kutorgina pusilla, Linnrs., lingulella sp., and Agnostus sp., K utorgina pusilla is known elsewhere only f rom the highest Paradoxides beds of Sweden. It is theref ore probable that the zone of P olyphyma marks the top of the Middle Cambrian. T he immediately overlying beds are not exposed, but by far the grea ter part of the shale series evidently belongs to the Upper Cambrian zone of S plzaroplztlzalmus alatus, Breck, which is very common in certain bands ; with this are associated Ct euo­ pyge bisulcata, Phil., C. pecten, Salt., Peltura scarabaoides, Wahl. , Agnostus trisectus, Salt., and Obolella (?) salteri. In limestone fragment s f ound among debris of the shales were obt ained Obolella (?) salteri ( ?), H oll. , and other fo ssils, to­ gether with numerous microscopic organisms, among which Mr. F. Chapman has detected ostracoda, echinoderm spines, and the earliest known well -preserved British foraminifera, belong­ ing to the genera Spirillina, Cristellaria, Marginulina , D enta ­ lina , and Lagena. F ollowing the White-leaved Oak Shales with apparent con­ formity are the Bronsil or Grey S hales (F ig. II6), a series pro ­ bably about 1 , 000 feet thi ck exclusive of associated igneous rocks . They are typical ly sof t, and where fr esh, of a light blue colour ; they are frequently indurated in the neighbourhood of the intrusive masses. The fossil s recorded inclu de the follow ­ ing: Dictyouema social e, Salter, Lingulella nicholsoni, Call., Aerotrela sabrinre, Ca ll., Linnarsonia beiti , Dav., Obolella (?) salteri, H oll. , Agnostus dux, Call., Clteirurus fr ederici , Salt., Asaphellus affin is, McCoy, Niobe (?) cf. peltata , and others, an assemblage cha racteristic of the Tremadoc beds of North Wales, and clearly belonging to the Eulonla-Niobe fauna in general. 704 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME.

IGNEOUS ROCKS ASSOCIATED WITH THE CAMBRIAN AND ORDOVICIAN. Associated with the older sedimentary beds of the Malverns is a series of igneous rocks" (Fig. II6), which have fre­ quently been supposed to mark eruptions at the surface in pre­ Silurian times. They occur in the form of sheets, small phaco­ lites, rounded bosses, and dykes. They have baked the overlying and underlying rocks j no tuffs appear to exist, though such were formerly described. The rocks are probably all intrusive. They invade the Cambrian and Ordovician strata, but not the Silurian, and the latest, at any rate, were evidently intruded after the deposition of the Bronsil Shales, but before that of the May Hill Sandstone. They are rarely well preserved, but it is clear that they comprise four distinct types. 1. Ophitic Olivine dolerites forming sills and small bosses in the Bronsil Shales. A similar rock has been detected in the Archsean of . 2. Olivine Basalts found in the form of sheets and small phacolites chiefly in the Cambrian and Ordovician shales. The only phenocrysts are serpentinous pseudomorphs after olivine. 3. Augite Basalt, with small phenocrysts of augit-e. One instance only. 4. Hornblende Basalts or Lamprophyres, occurring as dykes and small bosses in the Hollybush Sandstone, and as bosses and sheets in the Cambrian and Ordovician shales. They are com­ pact rocks with small phenocrysts of hornblende, augite, fels­ par, and ilmenite.

SILURIAN. The Silurian bedsj of the area have not of late received so much attention as the older beds, and the chief source of informa­ tion on this head is still Phillips' Memoir. But the succession conforms in general with that in Shropshire and other parts of the Midlands. It is as follows :- Probable Thickness in ft. LedbUry Beds . 40 0 DOWNTONIAN. { Downton Sandstone . roo Upper Ludlow Shales . 100-200 Aym estry Limestone .. 250 Lower Ludlow Shales . 70 0 SALOPIAN. Wenlock Limestone . 350-400 { Wenlock Shale . 850 Woolhope Limestone .. 10-25° roo VALENTIAN. {:ao;l~E~ ~~~~~s l···"\v;·~h··ii~·ci~.-·············· 500 stone. Cowleigh Park Beds. 42 0-90 0

'1< List of Works. No. 27. +List of Works, Nos. 3, 7, cr , Z3, 24_ THE MALVERN AND ABBERLEY HILLS.

The Silurian shales, as elsewhere in the Midlands, tend to form lower ground and valleys between the ridges formed by the limestones and sandstones (Figs. lIB and lI9). The May Hill Sandstone forms a fine escarpment around Bronsil, where it rests on the Bronsil Shales (Fig. 116). The Wool hope Limestone rarely forms any marked feature, but the Wenlock and Aymestry Limestones, especially the latter, generally give rise to con­ siderable escarpments. The thickness of the various members of the Silurian evi­ dently varies considerably in accordance with the amount of fold­ ing and squeezing they have undergone, and the estimates of the writer are taken from localities in which the folding is least. The 1l1ay Hill Sandstone consists of two fairly contrasted members; a lower and much thicker series, commonly plum-

FIG. 1I7.-SECTION ACROSS HICH WOOD AND NORTH HILL.-T. T. Groom.

W.byS. High Wood E.by N. \

[Scale : 6 inches ,e r mile.]

Tr. T rias. :\15, . L ower Beds of May H ill Sand- WS. Wenlock Shale . stone (Cowleigh Park Bcds. \\'1. ,. Woolh ope T.imestone. BS. W hite-leaved Oak Shales ( Cam . TS . Woolhope Shal es. bria n), ~IS.. Upper Beds of May H ill Arch. Archrean. Sandst one. (Wych Bed s). F1". Faults. coloured or brown, which may be termed the Cowleigh Park Beds/ and an upper, thinner series, which weather to a yellowish or pale brownish-grey colour, and may be termed the Wych Beds. The Cowleiglt Park beds (Figs. II7 and 119) consist of purple, brown, pink, green, and grey grits and sandstones, with subordinate conglomerates and shales. According to Phillips (No.3),* this subdivision perhaps attains a maximum tbickness of 700 feet. The writer considers that a thickness of 900 feet or more is probable near the northern end of the Malverns. At the southern end, where the succession still appears to be complete, the thickness is probably not more than 420 feet. In the locality first mentioned a grit or conglomerate, often pink in colour, but sometimes greenish, found some 300 feet below the top of the series, forms a small ridge running through Cowleigh Park. A * Figures in brackets in the text after the name of an author or of a work refer to the U List of Works" on p. 738. 47 706 GEOLOGISTS' ASSOCIATION JUBILEE VOLU.\1E.

somewhat similar rock is found about 130 feet below the top of the series near Bronsil. This suggests that the southerly thinning of the Cowleigh Park beds is not due, at any rate solely, to over­ lap of the basal beds, but in part to a thinning of the beds as a whole. The conglomerates have afforded an interesting assem­ blage of pebbles, which includes red aplite, sometimes micro­ graphic, diorite, rhyolites, and other volcanic rocks, sometimes glassy j also metamorphic quartzites and quartz-schists, quartz, untwinned and twinned felspars (including microcline), mica, and other minerals. The TVych beds (Figs. 117 and II9) are much more uniform in character than the underlying Cowleigh Park beds. In the weathered condition in which they are usually seen, they consist mainly of yellowish to pale brownish-grey sandstone, which are frequently platy or flaggy. These are interstratified with shales, which, according to Phillips (No.3), predominate in the upper part. At the northern end of the Malverns the thickness is about 500 feet. The series is nowhere really well exposed. The succeeding Woolhope Shales (Figs. 117, lIS and 119) correspond in position with the Tarannon Shales of other dis­ tricts. They are of no great thickness, and are rarely exposed. The best exposures are at Cowleigh Park, where the beds are green shales interstratified with purple shales, both with thin bands of limestone. The actual base is not seen, but the upper­ most layers of the Wych beds close by are interbedded with shale, and there may well be a passage between the two series. Farther south, at Birches Farm, the Wool hope Limestone is underlain by shales alternating with limestone. Shales in a cor- responding position were seen by Symonds and Lambert (No.5) in the Malvern tunnel, where they appear to be nearly 300 feet thick.* Elsewhere they can hardly be so thick as this, and, in the opinion of the writer, are in most places probably hardly more than 100 feet thick, and in some places probably less.

Paiaontolo gy of the Valentian.-The principal species re­ corded from the May Hill Sandstone, together with a few that I have been able to add myself, are shown in the table on pages 7II to 715· Among the most characteristic forms are Lindstromia sub­ du plicata, Siricklandinia lens, S. lirata, Pentamerus undatus, P. oblongus, Leptoccelia hemispharica, three species of Lingula, and five of Ctenodonta. The species of Ctenodonta have appar­ ently not been recorded except from the May Hill beds of the district. Tentaculites anglicus and Tetradella complicata have * The lower unfossiliferous part only of the shales is regarded by these authors as equivalent to the Tarannon. THE MALVERN AND ABBERLEY HILLS . lingered on fro m the Ordovician. T he earlies t known E urypterid, a species of P terygotus, and species of P aiteastcr and P ala­ echinus are found in these beds. F ew of the foregoing forms pa ss up int o the overlying beds. Other species, which in the Malvern district do not appear to have been fo und at a higher horizon , are: P ala: ocyclus praacutus, 111eristina ( ?) f urcata, Orthis calli­ gramma, O. uespertilia, Stroph omena ap planata, S . arenacea; S . pecten, S . simulans, Pterinea demissa, P . orbicularis, B ell e­ rophon acutus, Euomphaius corndensis, E. pra:1ll11ltius, H olopea striatella, H olopella cancella ta, H. gregarea, Ll1urcllisonia pryc ea: , Pleurotomaria fissicarina, Cyrtoceras ap -proximat um, and Orthoc eras cochleatum, Some of these, however, are known to occur at higher horizons in other districts. T he current lists of May Hill fossi ls stand in need of some revision, as appears to be shown by the inclusion of such form s as Orthis flaoellulum, A saphus tyrannus , and Trinucleus caractaci, Di sregarding the more doubtful cases, and others in which the pr ecise horizon is not recorded, it is clear that the greater part of th e Malvern May Hill fossils occur in the Cowleigh P ark beds. They numb er some 53 species. Of these, 9 pass up into the Wych beds. These are Cornulites serpuiarius, Stricklandina lens, 11/ eris­ tina (? ) f urcata , R llyn cllOnella decemplicata , Spirifer crisp us, Euomphalus corndensis, E ncrinurus punctatus, and the widely ranging forms Atry pa reticularis and L cpta na rltomboidalis. Favosites multipora, Dinobolus dauidsoni, P entam erus l a:vis , and Pleurotomaria fissicarina have been found only in the Wych beds. It would thu s appear that while the May Hill Sandstone is exceedin gly well characterised as a whole, its two subdivisions, though sufficientl y distinct lithologically, are not of great palseon­ tological importance, the chief distinction being that the Wych beds are relatively poor in fossi ls. F ew fossi ls have been recorded fro m the Woolhope Shales, though the upper part (which, however, may possibly be ulti ­ mately grouped with the Salopi an series) is stated to be fossil­ iferous.

S alopian S eries.-The Salopian series consists of shales and more or less earthy limestones. F ossils are not particularly abundant in the limestones, and the latter seem to be in no sense coral reefs. The series as a whole is, however, relati vely rich in fossils, a large proportion of which have not been recorded from the beds above or below (see table, pages 7II to 7r'j) . T he Wool/lOpe Limestone (F igs. 117, r rS and r rc), in the south ern pa rt of the Malvern district appears as a more or less 708 GEOLOGISTS 'ASSOCIATION JU BILEE VOLUME. nodul ar and argiHaceous limestone j but a little farther north it be­ comes divided into two by the interposition of a thin band of. sandstone and shal e. Still farther north, opposite the Worcester­ shire Beacon, the sandstones and shales become over 160 feet thick, the limestone below being 16 feet, and that above 25 feet thick. According to Phillips (N o.3), the series, while ranging in thickness from 10 to 250 feet, has an average thickness of 20 feet. Among the foss ils may be mentioned A try pa marginalis, E iclnaaldia capemellii, Ath yris depressa, Llf eristell a ( ?) circe, and L ichas ucrrucosus, none of which appear to have been found at oth er horizons in the district. No lamellibranchs and very few gasteropods or cephalopods have been recorded. The Woolhope Limestone passes up into the W enlock Shale (Figs. 117, II8, II9 and 120), a series of shales with a number of th in bands of limestone and nodular shale. Above, these pass into the Wenlock Limestone. Phillips (No. 3) gives the thickness of the series at about 640 feet, which is about that seen near West Mal vern j but in the opinion of the writer an estimate of 800 to 900 feet made about Nethe rton Farm is more likely to appro ach the original thickness in the di strict. The best exposure of the Wenlock Shale is in the railw ay cutting close to Colwall Station.. The Wenlock Shale fossils that do not ap pear to have been recorded from other beds in the district are: Cyathophyllllm fiexuosum, Pala ocy clus fletcheri, P. rugosus , P lasmop ara petal­ Lif ormis , S yringopora bifurcata , Cyphaspis pygm a:lls, Liehas salt eri , L . scutalis , and Eucrinus speciosus. The species of corals are fewer than in the May Hill Sandstone and Wenlock Lim e­ stone. No lamellibranchs have been recorded, and few gastero­ pods or cephalopods. The vVenlock Limestone (Figs. 119 and 120) is grey in colour, and has interbedded shales. One of the lowest bands shows well marked oolitic and pisolitic structure. In Eastnor P ark the ridge formed by the limestone has an artificial appear­ ance, and bear s the carriage-road known as the " rid geway." The limestones that are relati vely free fr om shale tend to form a set of minor parallel rid ges. Opposite the northern half of the Mal­ "ems 1 estimate the thi ckness at about 350 feet , and opposite the northern part of the central Mal vern s about 400, estimates greater than those of Phillips (No. 3)-100-280 feet. The Wenl ock Li mestone is apparently thicker in the Mal vern district than elsewhere. The foHowing fossils have been found in the limestone, but ap parently not at oth er horizon s in the district: Ca:nites inter­ textus, F avosites hi siu geri, H alys it es catenularius, Monticuli­ pora fietcheri , 111. pul chella , Cystiph yllum cylindricum, Pro-p ore tub ulata, Ptycho-phyllum patellatum , Stromatopora striatella, Strombodes phillipsii , S yringopora f ascicularis, Orbiculoid ea THE MALVERN AND ABBERLEY HILLS.

[or besi , O. verneuili , R etzia salteri, Rhyn chonella cuneata , R. stricklandi, Spirifer sulcatus, S trophomeua fil osa, E uom­ pllalus scul-ptus, P olytropina discors, Gom-p hoceras corona, Phragmocer as imbricatum, P. subexternum , Trochoceras gyrans, Crotalo crinus rugosus, P eriechocrin us monilif ormis, Encrinurus variolaris, I lla nus carinatu s, Liehas oarrand ei , L . grayi, and S taurocephalu s murchisoni. T he L ower Ludlow S hales are described by Phillips (No . 3) as grey shales, 700 feet thick, with band s and nodules of lime­ stone in the lower part. In the Lower Lu dlow Shales the species that have not been recorde d f rom other horizons in the district are : I schadites konigi, Monograptus chim e ra, M . scanicus, J/Il. uarians, Glassia obovata, L epta:na l a: vigat a, L ingula striata, Pholidops implicata, Cardiola fibrosa, C. interrapta, C. striata, Modiolopsis gradata, Pterin ea posidonia:formis , Orthonota rigida, Pseudaxinus secu­ riformis, Lo xonema intumescens (?), L. perneri, A cidasp is brigltti, Bronteus sp" and 29 cephalopods. F ew corals have been recorde d, and no echinodermata. The most characteristic feature is the wealth of cephalopods, over 40 species, nearly three-qu arters of which have not been found in the underl ying or overlying beds . T he Aymestry Limestone, accordi ng to Phillips (No .3), con­ sists of a series of blue limestone's with shal es, and varies fr om 10 to 40 feet in thickness. This is probably an underestimate, the .rock being ap pa rently much thicker in places j according to -P iper (No. 15), near Ledbury Station it is 236 feet thi ck, or with the underl ying passage beds, 250 feet. The limestone passes up into the Upper Ludlow Shales. T he rock is not rich in fossils j there are few corals, cephalopods, or trilobites j and no echino­ derrnata have been recorded . The following species do not appear to extend into the underl ying or overl ying beds : Conchi­ di um kniglttii , H ormotoma cingulata, H. pi-peri , L ox ouema pselldofa sciatum, and Pleurotomaria quadristriata.

D oumtonian.r-«The U pper Ludlow Shales are shales with thin shelly limestones j the upper part is very sand y and flaggy. Phillips (No.3) estim ates the thi ckness at from 100 to 200 feet. The Downton Sandstone, according to Phillips (No .3), is a brown, yellowish, grey, or whit e laminated sandstone, [0 to 100 feet thick, which passes down into the Upper Ludlow Shales. The beIs that foll ow the Downton Sandstone have commonly been termed the Ledbury Shales. Shales, however, are quite subordinate, and the term L edbury B eds seems more appropriate. The series consists essentially of chocolate-coloured, brown, or 710 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME. red argillaceous sandstones, often fissile (shaly sandstone). with subordinate grey sandstones, and red or green clays or shales. They are best exposed in the fine cutting at Ledbury Station, where, according to Piper (No. IS), they are 400 feet thick, an estimate that I can confirm. They pass up into the Old Red Sandstone.

Palaontoiogy oj the Downtonian.-In the Upper Ludlow Shales few trilobites and no echinodermata have been recorded. The cephalopods are mostly also found in the Lower Ludlow. The chief distinctive forms are lamellibranchs and gasteropods. The following fossils have not been recorded from other beds in the district: Cucullella antiqua, C. ovalis, Orthonota amygdalina, o. undata, Gonio phora cymoaformis, Bellero-phon expansus, B. murchisoni, Euomplzalus carinatus, H olopella obsoleta, Murelzi­ sonia corallii, and Orthoceras undulocinctum. Few fossils have been recorded from the Downton Sandstone of the district. Phillips (No.3) states that the lower part con­ tains a few fossils of Silurian type, the upper, carbonaceous material. The writer obtained Lingula sp., Pterygotus sp., Pachytheca, and fucoids at Wallsgrove Hill. The Ledbury Beds of Ledbury have afforded to the late Mr. Piper a fine series of fish and other remains. The chief fossils found in this locality are: Auchenaspis egertoni, Lank., A. salteri, Egerton, Cephalaspis murchisoni, Egerton, Climatius ornatus, Agassiz, Cyathaspis banksi, Huxley and Salter, Onchus murchisoni, Agassiz, Pterygotus sp., Lingula cornea, Sow., L. minima, Sow., Pterygotus, and Pachytlzeca. The lingulre are found in thin bands of grey shale, similar to that of the Upper Ludlow, the fish in the remaining beds, especially in certain bands. With the exception of Onelzus murchisoni none of these fossils have been recorded from the underlying Ludlow beds. In the Lower Old Red Sandstone of the district the following are recorded: Ceplzalaspis lyelli, Agassiz; C. salweyi, Egerton; Cyatlzaspis maccullouclzi, Woodw.; Didymaspis murchisoni, Agassiz; Onchus tenuistriatus, Agassiz; and Pteraspis rostratus, Agassiz. THE MALV ERN AND ABBERLEY HILLS. 71 1 LI ST OF FOSSI LS RE CORDED FROM THE SILU RIAN (MAY HILL SANDST ONE TO UPPER LUDLOW) OF THE DISTRICTS OF ABBERLEY, MALVERN, AND LEDBURY.

OJ '; "'.; a~ "'~ ~~ ~ ~ ~ ~ 0 0 ~~ ~o :r:S .a~ 'n -os""i5 ..!! ;0 - ;;~ " 0 "'"0 8~ ~.a ~ * 0"0 ~ "'-"0 "' ~ :;rn ...l" "," E Pj ~ ~ ~::3 :;j ...l -.:::3 ------_.------I schad/ftS Nih/igii, Mu rch...... , ... X .,. ... A Ioeolites /ab;:chei, M. Ed w...... X .., ...... Alueolites r epms, L oris...... X ...... X ...... Comites intertrxtus, Eichw...... I X ...... CYllthoplzy//um j/exuosum, Lons...... 0' X ...... Cvathap hyi/um cy/indr ieum , Lons, ...... X .., ...... Fa uosues asper, d 'O rb, ••• ...... X X ... X X ...... Faoosites goth/and/;;us, Linn . .., ... X ... XX ...... Fauosites llisingeri, M . Edw, ...... '" ... X ...... Fao csites mu /tiporus, Lons...... XX ... X ...... Haiysites catenular ius , Linn...... , X ...... H tliotitiS inte rstinctus, Wahl...... X X X X ...... Helzolites megastoma, M'Coy ...... X ...... X ...... '" L indstra mia sub-dupticata , M'Coy, ... X ...... L indstr amia sub-duplieata var, crenulata, I M'Coy .. . ." ...... X ...... Monograpt us chimcera, Barr ...... X I ...... Monograptus scanicus, Tullb, ...... X i ...... M onograptus uarians, Wood., var ...... X .. ... Monticu/ipora fibrosa, Goldf...... X ...... X X X X M ontiet< IijJoraj/dcheri, M. Edw...... X ...... M onticu/ipora pu /ch. /la, M. Edw ...... X ...... Omphyma sub-t ur binat um, d'Orb, ... X X ... X ... X ... Pakr ocyclus j/etclu r i, M. Edw...... X ...... P ala ocyclus pr(l!aet

LI ST OF FOSSILS.-Continued .

ag "U ..>c U »u -"

LI ST OF FOSSI LS.- Colltinued. ,.,.: =v. ~ c s. g ...... : 0 0 g ~ ~ ~ " c ~ :e.g ..<:- gE - 0 '"'~..2 ,.,~ c ~ ~- :G'th oV -C..<:'" 0'" S u c.." ~1 s s ~ en U E ..<" ,., S " en :>:;.:1 :>::.3 ..< "':;.:1 "'.3

s.tr;e/;Iant/inia lens, Sow. '" ... X .., ...... s./r ic/;/an dillia lira/a , Sow...... X .., ...... strophomena antiquata; Sow...... 'X .. , X '" X ...... s.trophomena app/ana/a, Salt, ...... X I .., ...... s.trophomena arenacea, Salt...... X .., ...... strophomena imbre», Pand o ...... , X ...... s:trophommapee/en, Linn...... X ...... strophomena simulans; M'Coy...... X .., ...... I ... s.troph,ot/on/a filosa, Sow...... , ... X ...... s.Irophonel/a tug~vpha , Dalrn. , I ...... X X X ! X S trophond/a funicuiata , M'Coy ...... , X XX ... i ... Whitfid dia tumida ; Dalrn...... XX ... '" A nodontopsis p eroualis Salt...... X ...... A nodontopsi: qutldratus, McCoy ...... , ...... X C.'ardiola fib rosa, Sow. '" ...... X ...... Cardiola interrupta, Sow...... X ...... C.'ardiola stria ta, Sow...... X ...... C'tenodonta deltoidea, Phil...... X ...... Ctenodon/a eastnori, Sow...... X ...... '" ...... Ctenodonta lingua/is, Phil...... X ...... Ctenodonta r hom boidea, Phil ...... X ...... Clm odon/a subtequalis, Sow...... X .. , ...... I ... Cucu/lt//a antiq ua , Sow...... , ...... ! X Cuculld la oualts, M'Coy ...... X Cu{ullt/la ova/a, Sow...... '" ... I X Goniophora cymbtEftrmis, Sow...... X illotiiolopsis gratiata, Salt, ...... X ... X Mytilus mytihmeris, Conr, ...... X ...... X ... j ... P teri nea demissa, Conr...... X ...... I ... Pterinea lineala, Goldf...... '" ...... X ...... X Pterinea oroicuiar is, M'Coy ...... X ." ...... I '" ...... Pterinea p osidoniteftrmis, M'Coy ...... X ...... Pterinea retrofiexa, Wahl...... X .,. ... X ...... I ... Pterinea tenuistriata, M'Coy , ...... X ... I X Orthonota am)1[t/alina, Sow...... X Orthonota rigida, Sow. '" ...... X .. ... Or/hono/a undata, Sow. '" ...... X P seudax inus seeun/ormis, M'Coy ...... '" ... X ...... A erocu/ia ha/iolis, Sow...... X ... X ...... B el/eropiron acutus , Sow. ..• ... ." X .,...... B tlltrophon di/a/atus, Sow...... X ...... X ... Bellerophon e:rpansus, Sow...... X .Bel/eraphon rnurclusoni, d'Orb...... X Be/teropho11 triloba/us, Sow...... X ." X X ...... Bellerophon wmlockmsls, Sow...... X X ...... '" Euomphalus carinatus; His...... X Euomphalus corndensis, Sow...... X ...... Euompiralus p ramu" tius, Phil...... X ...... E uomphalus sculplus, Sow...... X ... '" ... .Holopra stria/ella, Sow...... X .., ...... H olopt/la cancellara, Sow...... X .., ...... H olopella I!TtFaria , Sow...... X .., ...... 714 GE OLOGI ST S ' ASSOCIATION JUBILEE VOLUME.

LIST OF FOSSILS.-Continued. a ~ ~~ ...... u i;-li :t:E g.5i g,g t~ - 0 &~ = ~ ~ - ~~ ~~ "2~ e ll 0"" e ~ 8 ~6 ~3 ~"'""" ;:0; e ~ Ul ~;J ,..l Ul ~;J ~~

Holopdla obsoleta, Sow, ...... x ... I ...... Hormotoma articulata, Sow...... I X X ...... i ... H orm otoma cingulala, H is...... I ... X ... Hormotcma piperi, Donald ...... I ...... X ... Loxonema grindrodi. Donald '" ...... X X ... Loxon ema intumescens (f), Don ald ...... X .. ... L oxonema perneri, Donald ...... X ...... L oxonema pseudofasciatum . Donald ...... X ...... Loxonema sinuos um , Sow...... X .., ... X X X ... Mbrchisonia corallii, Sow...... X Murclltsonia IIoydi, Sow...... X X Mu rchisonia prycetE, Sow.. .. .,. ... X ...... Ple urotomaria fissicarina, P hil...... X ...... Ple urotomar ia quadrtstriata, Phil...... X ... Polytropina discors, Sow...... X ...... Poiytropina globosa, Schloth ...... X X X X Ascoceras uermiform e; Blake ...... I ...... X ...... Cyrtoceras appl'oximatum, Sow...... X ...... : ...... Cyrtcceras comp ressum ; Sow. ... '" ...... X ...... Cyrtoceras eqmseium, Blake ...... I ....I .. X ...... Cyrtocerasjortiusculum , Barr ...... X ...... Cyrtoaras magl/um , Blake ...... I ...... X '" ... Cyrtoceras reoersum, Blake ...... I ...... I ...... X ...... Cyrtoceras uranus, Barr...... X ...... Gomphoceras am).gdalis, Barr...... X ...... Gomphoceras cmctum, Blake ...... I ...... ? ...... Gomphoceras corona, Blake ...... X ...... Gomp hoceras crater, Blake ...... XX ...... Gomphoceras obouatum , Blake ...... I ...... X ...... Linares (n arietinus, Barr...... ! ...... X ...... L,tu,tes ,bex, Sow...... X .. . X N autilus bohem icus, Barr...... XX ...... I N autilus holianus, Blake ...... X ... I ... N autilus quadrans, Blake ...... '" ...... I XX ...... Ophidioceras articulatum, Sow...... ! X ... I ... Ophillioceras geometricum. Blake ...... I ... X ; ...... Orthoceras angbla/um , Wahl...... X X X XX ... X Orthoceras annulatum, Sow...... XXX X I ...... Ortsoceras ascendens , Blake ...... X ...... Ort hoceras bacchus, Barr...... X ...... I Ort hoceras barrandei, Salt...... X X ...... Orthoceras bullatum, Sow...... X ... X X Orthoceras cochlea/u rn, Schl oth ...... X ...... Orthoceras distans; Sow...... XX ...... Orthoceras duponti, Bar r...... X ...... Orthoceras /ilosum, Sow...... X ...... Orthoceras fimbr iatum, Sow...... X X ...... Or/hoceras grindrodi, Blake ...... X ...... Orthoceras ibex, Sow...... X ... X Orthoceras imbricatum, Wahl...... X ...... (,r/hoceros Iudens «, Sow...... XX ... X Orthoceras primtl'vum , Forbes ...... i ... X I ... X THE MALVERN AND ABBERLEY HILLS.

LIST OF FOSSILS.-Continued. --- ".; ~~ i::'~ ~ ~ "'000 -D. ;I; 2 A- o v -"~I~~go IV 0 ~~ ~.£ ~~ o~ "2~,,0: C m ~~ os "8 o-l" ",88 " ~.3 ~§ ~Ul ~.- o-l "'''' Ul ~:.:l o-l ' <:.:l

Orthoceras recticinctum, Blake ...... '" '" ... X ... X Orthoceras subeonieum, d'Orb ...... ? ...... '" ...... Orrsoceras subundulatum, Port...... -'" '" '" X ...... Orthoceras tenuiannulatum, M'Coy ...... '" ... X ...... Orthoceras undulocillctum, Blake .,...... '" ...... X Orthoeeras velatum, Blake ... '" ...... '" X X ...... Phragmoceras rxternum Blake ...... X ...... Phragmcceras imhrieatum, Barr ... . ,...... '" X ...... Phragmoceras subexternum, Blake ., ...... '" X ...... Phragmoceras ventl"-iCOSUln, Sow.... ., ...... X ... X ...... Trochoceras asperum, Barr ...... X X X ...... Trochoceras giganteum, Sow ...... X ...... Trochoceras gyra"s, Blake ...... X '" ...... Troehoeeras rapax; Barr ...... X ...... Trochoceras speetOSllm, Barr ... ., ...... X X X '" ... Trochoceras striatum, Blake ... ., ...... X ...... A cidaspis brighti, Murch ...... ,...... X ... '" Acidaspis coronata, Salt.... '" ...... X X ...... Bronteus sp, ...... , ...... X ...... Calymene blumenbachlt", Brong ... ., . X ... X X ...... Cheirllrus bimuero"atus, Murch. ... ., . ... X X X X ...... Cyphaspis megalops, M'Coy ...... X ... X ...... CJ'jJhaspis pygmtl'US, Salt...• ...... X ...... Encrinurus punctatus, Brunn, ...... X x X ...... Enerinurus uariolaris, Brong...... X ...... Homaionotus delphinocephalus, Green X ...... I ... Illamus barriensis, Murch. ... ." X X X X ...... Illamusearinatus,. Salt...... '" X ...... Ilkenus inslg"is, Hall ...... , ...... X ...... Liehas harrandei, Fletch...... X '" ...... Lichas grayi, Fletch...... '" X ...... Lichas salteri, Fletch...... X ...... Lichas scutalis, Reed ...... ,...... X ... '" ...... Lichas verrUCGSUS, Salt...... " ... X ...... Phacops caudatus, Briinn...... X X X X X X '" Phacops dowmngitl', Murch. ... ." ... X X X X X ... Phacops longicaudatus, Murch...... '" X X ...... Phacops musheni, Salt...... , . X ... X ...... Phacops stokesi, Edw...... X ...... X '" ...... ProNus latifrons, M'Coy ...... X ...... X ...... Proetus stoeesi, Murch. ... I ...... X I ... '" ... X ... X Sphlerexochus mirus, Beyr. ... ." ... X X X ...... S1aurocephalus murchisOlli, Barr...... '" ... '" X ... '" ... Tdradella complicata, Salt. ... .,. X ...... Crotalocrinus rugosus, Mill...... X ...... Eucrinus speciosus, Ang...... " ... X ...... Periechocrinus moniliformis, Mill ." ...... '" X '" ...... Pisocrinus pilula, Ron, ...... ,.. X X ... '" ...... Sc aieocystis armatus, Forbes ...... I... X X ...... Pa/alaster coronella, Salt...... X ... -...... Paltl'~chinus phillipsii, Forbes ...... X I...... '" ...... I I I 716 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME.

PART Il.-TECTONIC STRUCTURE. The most striking structural features in the Malvern and Abberley districts are perhaps due to the contrast in the be­ haviour of the newer and older rocks. In general the older rocks from the Archrean to the Old Red Sandstone show considerable folding, and in the immediate neighbourhood of the hills over­ folding and overthrusting. On the other hand, the post-Car­ boniferous rocks are usually gently inclined, and rest with a striking unconformity on the older series. The Carboniferous formation in part shares the folding of the older rocks, and in part the low dip of the overlying beds. In the older series the ancient core of the Malvern Hills behaves independently of the associated Lower Palseozoic rocks; and in the newer, the rocks of the plains to the east of the hills are separated by a great fault from the relics of post-Carboniferous rocks now capping the hills. It will accordingly be convenient to treat the subject under the following headings:

1. The Core of the Malvern Hills. 2. The Disposition of the Pre-Carboniferous Palseozoic rocks. 3. The Coalfields. 4. The Cover of Haffield Breccia. 5. The Midland Plain.

1. THE CORE OF THE MALVERN HILLS.* In general older and older Palseozoic rocks crop out as the Malvern Hills are approached, and it seems natural to conclude that the crystalline rocks of the hills form the core of the Mal­ vern anticline (see p. 720). But nowhere is there clear evidence that the Paleeozoic beds west of the hills ever rested on these particular crystalline rocks, and the fault that defines the latter on the west, like the belt of over folding by which it is accom­ panied, shows a considerable amount of independence of the folding that produced the anticline. In general the belt of inversion follows the sinuous margin of the overthrust Archaean massif to a remarkable extent; its independence of the horizon of the overfolded beds seems to indicate that the overfolding was closely connected with the overthrusting, and was partly independent of the Malvern anticline. This is particularly clear along the north-western margin of Chase End Hill, where the belt of overfolding runs nearly at right angles to the strike of the Palseozoic beds. These facts seem to suggest that the Malvern Archseans do not form a part of the core of the Malvern anti­ cline, but belong to some fold or folds farther east, and have been displaced to the west along the thrust plane. That the * List of Works, Nos. 23 and 24- THE MALVERN AND ABB E RL EY HILLS. overthrust was to a certa in extent independent of the ear lier movement s is further indicated by the fa ct that the Palseozoic rocks are traversed by a series of transverse faults, many of which terminate at the bord er of the Archae an massif. T he over­ th rusting in the district probably took pl ace in more than one stage, for the overthrust mass of the Mal verns apparently over­ rides the Cowle igh P ark thru st, and itself seems to be overridde n by the Chase End mass. Accordingly, it seems safest to treat the core independently of the Malvern anticline. T he Malvern Hills owe their height chiefly to the durabi lit y of the Archrean rocks of which they are mainly composed. The Archsean is continuous from end to end of the hills, except at the " Silurian Pass," where an oblique strip of May Hill Sand stone intersect s it. The genera l nort herly trend of the strip of

FIG. lI8. -SECTION 0.' TilE R ANG E ALONG THE LINE OF THE MALVERN T UNNEL.-T. T. Groom, [Scale : 4~ inches» I mile.]

r r. Railway level . e. \,"enlock ha le . F 'F '. Fault between Trias and Arch aean . d . Woo lhope Limeston e . FF. F aults. c . W oo lhope hale s. Br ecci a. b . Mav II ill an dstone. t Tria s a. Arch zean. Archsean is determined by two sub-pa rallel f aults. T he eastern side is defined by a normal f au lt with a maximum throw of some 1 , 000 feet, along which the Trias has been dropped to the level of the Archrean . In one locality only, east of Swin yard Hill, do any P alseozoic beds intervene betwee n the Trias and the Archaea n. On the western side the Archtean is thru st onto various members of the Lower P alseozoic, fro m the Malvern Quartzite to the Wen­ lock Shale. In the Mal vern tu nnel the faul t hades to the east (Fig. 118). The foliation of the gneisses and schists as a rul e shows little relation to the direction of the boundary faults, or to the strik e of the flanking Palseozoic strata. It is more commonly oblique or transverse, and thi s gives to the hills a plagioc1 inal struc­ ture. * The dips and strikes, however, vary greatly, in such a way as to suggest complex folding and faulting, but so little is known of the detailed structure that it is not possible to give any idea of the prevailing directions of the folds. Occasionall y, as, for example, towards the south ern end of the range, the foliation • L ist of W orks, No .8. 718 GEOLOGISTS ' ASSOCIATION J UBILEE V OLU M E. appears to be related to the line of thrusting in a mann er that suggests a secondary producti on of schists from th e old materi al. Within the area occupied hy the Archsean there are strips and patches of later rocks. These include the Malvern Quartzite, H oll ybush Sandstone, and May Hill Sandstone. T hey not im­ probably represent po rtions of crushed and di slocated in folds. The most conspicuous of these occur along a curved line travers­ ing Mid summer Hill and the Ragged stone (F ig. 116, and Plate XXIII, Fig. 1). The fo liation of the adjoining schists is often paralle l to thi s line, and possibl y origina ted at the time of the movements that produced the infold. In the northern Malverns a series of strips ot May Hill Sandstone are inclu ded in the Archrean close to its western bord er. One of these was observed by Symonds and Lambert (No.5) in the Malvern tunnel, and pr esumably the same in the Wy ch Pass above (Fig. II8). Others are found on the western side of North Hill (Fig. 11/). To one of these, not hitherto known, the attention of the writer was drawn by Mr. H. D. Acland. This was exposed during quarry­ ing operations at the mouth of " T he Dingle," between N orth H ill and the .

_. THE DISPOSITION OF TIlE PRE· CARBONIFEROUS P AL£OZOIC ROCKS.* The disposition of the rocks older than the Coal Measures may convenientl y be taken together, since ap art from the break between the Bronsil Shales and th e May Hill San dstone the suc­ cession, so far as can be seen, is continuous from th e Lower Cam­ brian to the Old Red Sandstone. In striking contrast to the Haffield Breccia and highest Coal Measure s, the older rocks of the district have been greatly folded and faulted over much of th e area, and in part overfolded and overthrust. Details as to the arrangement of the fol ds and faults in much of the area are still lacking, but some of the main structural f eatures of the district are clear. This is more particularly tru e of the area south of the river Teme. (a) The Storridge Anticline.-This name may be conveni­ ently applied to a fold running from near Alfric to Cowleigh Park at the northern end of the Malverns. From the Surv ey Map and Memoir (No.3), it is clear that we have along this line a normal anticline, th e core of which is formed by the May Hill Sandstone, the lower division of which appears in places. On the west the whole of toe overlying Silurian beds are visible, but on the east the fold is truncated by the Malvern fault, so th at no bed s newer than the Wenlock Limestone have been recognised. T o­ wards Cowleigh Park comp lications are visible. Near New Inn

'1< L ist of Works, Nos. ?, 5-7, 17, 21,23, 24_ THE MALVERN AND ABBERLEY HILLS. j l 9

the Wenlock Limestone, with a south-westerly dip, is faulted aga inst the Wenlock Shale, and is possibly inverted and thru st over the latter, and near Hill F arm the fold is intersected by a tr ansverse fault. (b) The Cowl eigh Park F olds.-The western limb of the Storridge anticline is continued through Cowleigh P ark and down the western side of the Mal vern Hills, at any rate as f ar as the H erefordshire Beacon. But the eastern limb of the fold is not visible anyw here to the south of Storr idge Hill.

FIG. 119.-St:CTIOX ACROSS COWU;IGII PARK AXil 111 (;11 W o u n , - 1: T. Groom. [ Hcrizorual scale : 3 inches =, mile.l S.\\". :\'.E. Grc:\l Vineyard II igh \\"ood. Cowleil:h WoO

TR. Tria s. :\1 • . ppcr beds of :\Iay II ill 5 11 . Wenlock or Lower Ludlow - andstone (Wych Beds) . Shales. :\15, . Lower Beds of :\(ay H ill W l. e-\\'cnl,)(·k I.imcstone . Sand tone ( Cowlcigh Park Bed ). \\"• . Wenlock ·hale. Q. Cambrian Quartzite. \VL ,.\\"oolhopc Limestone. Ar ch . Ar chrean. T . Woolhope "h ale:. F F. F ault s. In Cowleigh Park, around a centre form ed by three small patches of Archrean, the Silurian beds of Rough Wood and H igh Wood are thrown into an overfo ld (Fig. 119 ), the axial plane of which has an easte rl y dip. The dip becomes norm al towards the west, so that onl y the May Hill Sandstone, Woolhope Lime­ stone, and the lower pa rt of the Wenlock Shales are overfolded. The three Arch aean pa tches are situated along a fault running south-south-east, and in connection with the sout hernmost is a small strip of quart zite, evidently the Cambrian Qu art zite. The same fault was appar entl y met with in a well on the slopes of North Hill, and showed an easterly hade j alon g thi s the Cam­ brian Shales have been thrust on to the inverted May H ill Sand ­ stone. The thrust plane is probably truncated here and there by a second nearly parallel fault by means of which a broken pa tch of Silurian, including an overfolde d mass of Wenlock Limestone, is brought into cont act with the Archrean and Ma y Hill Sand­ stone. It is possible that one of these faults is related to the cur ved fault at New I nn. It is not clea r whether the Archsean 720 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME. and Cambrian patches of Cowleigh Park represent portions of the core of a continuation of the Storridge anticline, or of some fold originally situated to the east. (c) The Malvern Anticline.-The western limb of the western Cowleigh Park fold is continued down the whole length of the Malvern chain, the Silurian and older Pal::eozoic rocks of which form the western portion of an anticline. This may be termed the Malvern fold (Figs. 119 and 120). The eastern limb is no­ where traceable, unless, indeed, on the eastern side of Swinyard Hill j for the beds, frequently overturned, are truncated every­ where by a great thrust that brings the Arch::ean into contact in turn with all the Pal::eozoic rocks older than the Wenlock Lime­ stone j on the north, with various horizons of the May Hill Sand­ stone (Fig. II7) j opposite the Herefordshire Beacon (Fig. 120), with the Woolhope Limestone and Wenlock Shale j opposite Swinyard Hill, with the May Hill Sandstone again, and farther south, with various members of the Cambrian and with the FH:. 120 .- S t:CTlO:-; ,\ CROSS TilE H EREFO ROSH1I1E lI t; ACO:-; A:-;O BRo.\1l Dowx.i--Z'. T. Groom. (R,pro dllud by pamisri oll of Iii, CO/IIt,il of t lrc Geol og u:« ! S ociery. } Oldcastlo Farm. Herefordshire Deacon. H ill Fa rm. :W.30"N. Mnll(. F.,\ E.30'5.\ ~ F. ...a~~_T i n kc r 's Hill F. i :~ o< ' ;':~,?,~ , 1 : ~~~~ ~. ~ ' - ''i> F ~ , -'- =--- ·""","t~'" WL2 WS WqS 'I,lS2 M olv. Ur F T I' :' la h·.-:'Ilah·ernian. r.- Warren House Serie s. LL .-Lower Ludlow. The remaining symbols as in Fig. I l l) . Bronsil Shales (Fig. 116). The Malvern fold is clearly a con­ tinuation of the anticline of Storridge and the western side of Cowleigh Park. But the uplift has been greater, so that to the south beds low in the Cambrian series come to the surface. The structure is simplest west of North Hill and the War­ cestershire Beacon (Fig. 117). The whole of the Silurian series from the purple division (Cowleigh Park beds) of the May Hill Sandstone to the Old Red Sandstone is present. Opposite the ex­ treme north end of North Hill, the belt of inverted strata is narrow, so that only the lowest Cowleigh Park beds are over­ turned, but to the south the belt widens and extends to the Wen­ lock Shales, the beds dipping eastwards at angles sometimes as low as 25°. Near Colwall and farther south a number of north­ west faults dislocate the strata j the most conspicuous of these brings the Wenlock Limestone against the Old Red Sandstone close to the mouth of the railway tunnel at Colwall. South of Hillside the Cowleigh Park beds disappear, and the Wych beds come into contact with the Arch::ean j this relation persists as far south as the Gullet Pass, except west of the Herefordshire Beacon THE MALVERN AND ABBERLEY HILLS. 72 1

(Fig. 120), where the Archsean transgresses across the Woolhope Limestone and comes into contact with the Wenlock Shale. H alf-way between the Gullet P ass and Bronsil Castle the main outcrop of the May Hill Sandstone retires from the hills, and revealing for the first time its actual base, becomes separated from the Archaean of Midsummer and Raggedstone Hills by a f aulted complex of Cambrian rocks, Bronsil Shales, and May Hill Sandstone. On the west the Bronsil Shales immediately underlie the purple May Hill beds, and south-w est of Ragged­ stone Hill are themselves und erlain by the White-leaved Oak Shales (Fig. II6). But these beds are tr aversed by considerable faults, and the cont inuity of the shales is interrupted by infaulted patches of May Hill Sandsto ne. The belt is moreover separated from the Archsean by a faulted pa tchwork of H ollybush Sandstone and Quartzite, and the whole compl ex is invaded by sheets, small bosses, and dykes of intrusive rocks. The intrusions commonly form elevated grou nd . The stru cture is simplest near White­ leaved Oak, as may be seen in F ig. II6. The White-leaved Oak Shales are inverted fo r a short distance from their junction with the Hollybush Sandstone of , and also along the north- western border of Chase End Hill. (d) The Eastnor S yn cline and th« Bradlow H ill Anticline.­ West of the south ern two-thirds of the Malverns lies the Silurian district of Eastnor and Ledbury. The structure of thi s district still awaits detailed elucidation, but some of the main outlines are clear. Viewed broadl y, the centre of the area is occupied by a syncline, the axis of which runs from Eastnor north by east in the direction of Colwall . This fold, which may be termed the Eastnor syncline, is bounded on the east by the Malvern anti­ cline, and on the }.V est by a second anticline- the Bradlow H ill anticline, which runs f rom Conygree Wood thr ough Bradlow H ill. The axis of the syncline di ps in a northerl y direction , so that the Old Red Sandstone near Colwall app ears as a bay in the Silurian, running in the direction of E astnor. The centre of the syncline farther south is occupied by the Upper Ludlow beds j the Aymestry Limestone is traced in the Survey Maps almost uninterruptedl y around the basin. The basin, however, like the anticline to the west, is not quite simple in structure, inasmuch as it is complicated by subordinate folds. One of the most conspicuous of these is the ill athon anticline, a narrow ant i­ cline east of Mathon, which is shown on the Survey Map as bringing up the Ludlow rocks in the form of a promontory in­ vading the area of the Old Red Sandstone, and causing a triple line of outcrop of the Aymestry Limestone and Up per Ludlow. The 111ath on syncline between thi s and the Malvern anticline pos­ sibly corresponds to the inverted Ockridge syncline west of Ockridge. This is separated from the main Colwall syncline 48 ;22 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME. by the gentle Ockridge anticline. West of Swinyard Hill is the narrow inverted Walm's Well Syncline. (e) The Dymock Syncline.-Some miles to the west-south­ west of the Silurian Hills of Ledbury and Eastnor lies the anti­ clinal dome of Silurians forming the Wool hope Hills and their prolongation in the direction of May Hill. Along the same line runs the main axis of May Hill. The intervening ground is occupied by a considerable syncline of Old Red Sandstone, which may be termed the Dymock syncline (PI. XXIII, Fig. 2). Judging by the few dips given on the Survey Map, the axis of the syncline lies near Donnington, which is much nearer to the Led­ bury Hills than to the Wool hope Hills and May Hill. This is just what might be expected from the high dip of the Silurians to the east-north-east of the syncline compared with the low dips to the west-south-west. The axial plane of the syncline accordingly dips to the east-north-east. To the south-south-east the continua­ tion of the syncline is concealed by the overlying Coal "Measures and Trias of Newent. (I) General.-Viewing generally the disposition of the pre­ Carboniferous rocks of the Malverns and district to the west, a re­ markable resemblance to the front of an old mountain range becomes apparent. The rocks of the dissected Herefordshire plateau, in general, arranged in gentle anticlines and synclines, towards the Malverns become more sharply folded; the axis of the folds dips towards the east, and in the immediate neighbour­ hood of the Malvern hills the beds are generally overf'olded. Closely connected with the overfolding is the overthrusting of the 'Core of the Malvern Hills, which itself appears to be a folded mass of rocks, chiefly Archeean, but with crushed infolds or in­ faulted slips of Palseozoic rocks. The overthrust has been from the east in the direction of the foothills formed by the smaller and more advanced folds of the Ledbury district. Closely related to these folds are those of the Woolhope Hills, May Hill, and the Forest of Dean mentioned above.

3. THE COALFIELDS. * The Carboniferous rocks of the district are limited to certain Coal Measures. These are developed mainly at the two ends of the Malvern-Abberley range. Beyond the southern end they form the Neioent Coalfield (Plate XXIII, Fig. 2), which is largely buried beneath the Keuper Sandstone, but has a long, nearly continuous outcrop on the west between this forma­ tion and the Old Red Sandstone. Along this line, according to Murchison (No. I), the coals were formerly worked in open quarries, The general dip of the Coal Measures, like that of

* List of Works, Nos. 1,3, 17, 24. "'l O~TIOl\' N FI G. 12 1. - S r.CT IO N ACROSS 'V OODn e RY AND " ' AI.I.SGROVF. H I LI.S Al\'D r n s ADp CF.NT I' OF T Il F. WVRE ,F ORF.ST r-, COA I.FIt: LD. - T . T. Groom.

Hcrlzorunl scale ::. .. inche... to the mile. N.W. S.!!•

.n >-l >-l .... P::

>< I-l W a lth onse ~ I-l < ORS OI~S \Tr ::a 1 1 FI :cr.:J (-; Tr. Tr ia s. AL. Aym est ry Lirne st-me. lI B. H atfield Brecci a. 1.1.. Low er Ludlow.

Coal ~Ieasures. 01. w r.0 ' Wenl oc k Limestone. OR S. Old Red Sand stone an d Passage-beds. Flo'. Fault s, UI. . Upper L udlow. Cf. I lypot hetical Fault s.

RI'P,odu(~J ( by P,." "i u ioll 01 II" C"'1I1( i/ oj I I" C~o!oKl(/ sO aC/",'",) 724 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME. the overlying Keuper Sandstone, is easterly, an indication that tilting has taken place since the Keuper times along a north and south line between the Malverns and May Hill, the rise being to the west. A small patch of Coal Measures occurs at the southern end of Storridge Hill; a second between the Old Red Sandstone and the Haffield Breccia of Berrow Hill; a third, a little to the north, at a point south-west of Martley, probably rests on an overfolded series of Old Red Sandstone, Cambrian, and Archsean. A fourth patch occurs between the overfolded Silurians of Wood­ bury Hill and the overlying Haffield Breccia (Fig. 121). Another patch has been stated to exist on the hill west of the Hundred House, but a personal examination of the beds left no doubt in the mind of the writer that these were carbonaceous parts of the passage beds between the Silurian and Old Red Sandstone. The relatively undisturbed lie of most of these patches, especi­ ally that of Woodbury Hill, appears to afford clear evidence that the great folding of the Abberley Hills antedates not only the times of the Haffield Breccia, but also those of the particular Coal Measures in question. At the northern end of the Abberlev Hills is situated the southern part of the Forest of TVyre"Coaljield (Fig. 121). The Coal Measures here rest directly on the Old Red Sandstone. Judging from the Survey maps and sections, the dips of the Coal Measures are not very different from those of the underlying Old Red Sandstone; west of Woodbury Hill the writer could detect no difference. Over much of the area the dips appear to be low, the beds being thrown into gentle synclines and anticlines, but in the immediate neighbourhood of the Trimpley Anticline and of the Abberley Hills the Old Red Sandstone, together with the apparently conformable Coal Measures, share in t~e marked overfoldings of the rocks of the hills. On Woodbury Hill Coal Measures evidently rest with striking unconformity on the same overfolded series. These relations are shown in Fig. 12I. The facts are very difficult to explain on any other supposition than that we are dealing with two different parts of the Coal Measures separated by an unconformity. The relations of the various rocks, indeed, go far to prove that the great folding and faulting of the rocks of Woodbury Hill took place in Coal Measure times. It is, however, probable that these were not the only move­ ments that took place in the region during Coal Measure times. At no great distance to the north of Abberley Hill. Mr. Daniel Jones (No. 17) traces' an unconformity beneath the Coal Measures which constitute the greater part of the Forest of Wyre· Coalfield. Near the base is found the main sulphur coal, and above this a Spirorbis-limestone. These Mr. Jones traces over the whole coalfield. Over much of the area, including the tongue- THE MALVERN AND ABBERLEY HILLS. already mentioned, which shares in the inversion of the Old Red Sandstone, these measures rest directly on the Old Red Sand­ stone. But near Kirilet they are separated from the Old Red Sand­ stone by an unconformably underlying series of older measures, including the sweet coals. If now the main sulphur coal and the Spirorbis limestone are really continued into the tongue, it follows that the unconformity near Kinlet cannot be the same as that on Woodbury Hill, but must be of earlier date.

4. THE COVER OF HAFFIELD BRECCIA. The Haffield Breccia* resembles the succeeding Trias in its gentle or moderate dip. It rests with marked unconformity on various older rocks. In Woodbury Hill (Fig. 121) it lies partly on Coal Measures, but. mainly on overfolded Salopian and Downtonian beds. In Berrow Hill it rests on Coal Measures, traces of the former working of which are still visible. Imme­ diately south of this it is in contact with Silurian limestones and shales, and north of Knightwick it is mapped by the Survey as resting on the May Hill Sandstone. At Knightwick, and pro­ bably also at Alfric, it is in contact with Silurian Shales. At Whippets, north-west of North Malvern, it appears to rest on the lower May Hill beds. At North Malvern a patch has been stated to rest on the Archtean. At the southern end of the Malverns it seems to transgress from the Archeean across the Cambrian, the Bronsil Shales, May Rill Sandstone, onto Silurian shales and limestones; and west of Bromesberrow from the Silurian onto the Old Red Sandstone. This is the most southerly known out­ crop in England of the "Permian" of the Midland type. A little farther south it fails to appear between the Upper Keuper Sandstone and the underlying Coal Measures or Old Red Sand­ stone (Plate XXIII, Fig. 2). It is evident that the Raffield Breccia, now represented by isolated patches forming some of the higher summits in the district, is but the relic of a sheet that once probably covered the district, and rested with a gently undulating base on practically all the older rocks in turn.

5. THE MIDLAND PLAIN.t The geological structure of the district between Abberley and Bromesberrow differs strikingly on the two sides of the great fault that runs along the eastern foot of the hills for their whole length. This fault may be conveniently termed the Malvern fault (Figs. 116, 117, 118, 119 and 120). To the east there is a :~ List of Works, Nos. 3, 7, 23, 24. t List of Works, Nos. 3, 23, 24. 726 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME.

succession of Triassic beds, capped on Berrow Rill by the Lias. The beds are thrown into gentle undulations, some of which in the neighbourhood of Castlemorton and Berrow are well shown in the Survey Map and Memoir. The general dip is to the south, the older beds having their main outcrops to the north. But there is also a tendency for the older beds to rise in the immediate vicinity of the hills, so that the dip is frequently to the east. The folds of the Trias are, however, largely indepen­ dent of the Malvern fault, and of the folds of the Paleeozoic rocks. In no single case is it clear that a fold in the Trias has affected the older rocks west of the fault, a circumstance which suggests that the folding of the Trias is in part, at any rate, later than the prcluction of the fault. The base of the Trias is not certainly reached at any point to the east of the fault, though at Alfric the Upper Bunter Sandstone is faulted against a patch of Haffield Breccia. On the western side of the fault, about Bromesberrow, the Upper Bunter Sandstone dips south, away from the Raffield Breccia, though the actual junction is probably a fault. Near Knightwick, however, the same sandstone is seen resting on the breccia with no visible difference in dip. This sandstone probably forms the base of the Trias along the greater part or whole of the Malvern and Abberley Hills. But a little to the north-east, near Stourport, the Bunter Pebble bed and the Lower Bunter Sandstone appear. South of Bromesberrow the Upper Keuper Sandstone rests on the Coal Measures, or on the Old Red Sandstone. Thus, passing from north to south, the upper members of the Trias overlap or overstep the lower, and rest directly on older rocks, at first on the Raffield Breccia, and then on the Coal Measures and Old Red Sandstone. Judging from the thickness of the Trias at the Malvern fault, this formation must have formerly extended well over the site of the Malvern and Abberley Hills on to the area of the Old Red Sandstone, a conclusion confirmed by the absence of a marginal facies in the neighbourhood of the Malvern fault, and by the super-position of the Upper Bunter Sandstone on the Haffield Breccia near Knightwick.

PART IlL-HISTORY OF THE AREA.

The early history of the district is involved in obscurity. Our knowledge of the constitution and structure of the complex of Malvernian rocks is still very inadequate. According to Rutley (No. II), it consists of tuffs or of sedimentary rocks derived from the denudation of igneous rocks, together with grits and sand­ stones, invaded by igneous rocks, and now altered into schists and gneisses, the foliation of which marks the old planes of THE MA LV ERN AND ABBE RLE Y HILLS. strat ification. No undoubted sedimenta ry rock has, however, been detected in the assemblage, and Dr. CaIIaway (Nos. 9, 10, 13, 16) regards it as essentially a complex of plutonic rocks, chiefly diorite and binary granite, now largely converted by dynamo-metamorphism into schist s and gneisses. It is evident, however, that at some period before the deposi­ tion of the Cambria n series volcanic action resulted in the emis­ sion of the rhyolites and other lavas, and the tuffs of the H ere­ fordshire Beacon. T hese resemble the pre-Cambrian volcanic rocks of Shro pshire, and are probably of the same age. No sedimenta ry rocks have l.een detected among them, a fact which f avours the view that the volcanoes were terrestri al. There is, however, no proof of the establishment in the district of the terrestr ial condition of the T orri donian period j but both to the north- north-west in Shropshire, and to the south at May H ill there are rocks compa rable with the Torridonian, and it may be that in the intervening Malvern area such rocks formerly existed, but have since been either faulted out, or removed by denudation. It seems probable that the district, like others in the British Islands, had a long and eventful pre -Cambrian history mark ed by great earth movement s, the intrusion of igneous rocks, and the extrusion of piles of volcanic material. These movement s and int rusions, as in the case of the H ebridean gneisses, may have given to the Malvernian rocks their meta­ morphic character and disposition. It seems possible, indeed, that the gneissic rocks of the Malvems mark a portion of an ancient pre-Ca mbria n mountain range, the di rection of which, as is ind icated by the plagioclina l structure, crossed the trend of the present hills. The nature of the pre-Cambrian lands at the commencement of Ca mbrian times is partly ind icated by the materials of the Malvern Quartzite. The inclusion of pebbles of binary granite, and rhyolites suggests that rocks of both Mal verni an and Uri­ conian type in their prese nt condition were then exposed at no great distance awa y, and the occasiona l occurrence of pebbles of sedimentary rock (sandstone and clas tic quartzite) indicates the presence of a thi rd element, perhaps the Longmyndian. But there is no evidence to show the relati ve ages of these formation s. At the close of the Archrean period the Malvern area, to­ gether with much of the English Midlands, sank beneath the sea­ level, and the Cambrian Quartzite was deposited, probably upon the denuded edges of the older series. Its more purely arena­ ceous character suggests a source different from that of the Lower Cam brian of Wal es. Moreover, the f airly large size of many of the pebbles of the Ca mbrian Quartzite in various parts of the English Midlands points to the proximity of a shore line ; and the OCcurrence of certain types of pre-Cambrian rock limited chiefly to the Midl ands, for instance the red granites and grano- 728 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME. phyres, is equally suggestive of a source in the Midlands. It is probable, therefore, that the whole of the English Midlands were not submerged in the seas of early Cambrian times, but stood out in the form of one or more land masses. As shown by the pebbles, the rocks of this land included vein-quartz often squeezed, metamorphic quartzite, quartz-schist, mica-schist, chlorite-schist, pink granite, diorite, andesite, and rhyolites. The Hollybush Sandstone is rarely conglomeratic, and the nature of the original rocks from which it is derived is less easy to determine, but so far as can be seen the materials had a similar derivation. The chief difference from the Quartzite is in the great abundance of glauconite. Towards the end of Middle Cambrian times the water presumably became deeper, as is indicated by the prevailingly argillaceous character of the sediments of the zone of Polyphyma. Similar conditions prevailed into Tremadoc times. As to the history of the area in later Ordovician times we are still in the dark, for Ordovician rocks later than the Tremadoc are absent from an area embracing the Malvern and Abberley districts, the eastern part of South Shropshire, South Stafford­ shire and Warwickshire. This has been explained* in Shropshire by supposing that the different members of the Ordovician of the Shelve district have disappeared towards the east by overlap against the shores of an Ordovician island. But there is no clear evidence of this overlap; the Bala beds seen in the Caradoc district may equally well have overstepped the rest of the Ordo­ vician, and farther east may themselves have been removed by denudation at the commencement of the Silurian times. There is, in fact, no proof that the Arenig, Llandeilo, and Bala beds were not deposited over parts of the Midland area. It does not, therefore, appear safe to conclude that the Midland area was land throughout Arenig, Llandeilo and Bala times. The first definite indication of land in the district appears to be the unconformity at the base of the Caradoc in South East Shrop­ shire.At a later date the evidence is more satisfactory. The pre­ sence of coarse pebble beds at the base of the May Hill Sandstone of the Midlands, and the considerable unconformity at the base of this formation, clearly indicates the existence of neighbouring land during the deposition of the May Hill Sandstone (Upper Llandovery), and judging from the absence of the Lower Lland­ overy it would seem probable that the chief movement of up­ heaval took place early in Llandovery times. Some idea of the constitution of this land may be obtained from a study of the pebbles in the May Hill Sandstone, but little information on this head is at hand. In the Malvern area the pebbles include aplites and diorites, recalling the Malvernian rocks, and rhyo- * List of Works, No, 14. THE M ALV ERN AND ABBERLEY HI LLS. 729 lites resembling those of the Uriconian and of the Warren House series. Judging fr om the disposition and thickness of the May Hill Sandstone, it must have completely covered the site of the Mal vern and Abberley Hills. Continued subsi dence during the remainder of Silurian times kept the district beneath the sea-level. The greatest depth of water was probably reached in Lower Ludlow times, the pelag ic cond ition of which per mitted the estab lishment of a great assemblage of Cephalopods and some gra ptolites. T owards the end of Silurian times the terrestrial condi tions of the Old Red Sandstone were inaugur ated, and the typical marine f aun a gave pl ace to the collection of fish and other organisms preserved in the red Ledbury beds. The Lower Old Red Sandstone contrasts with the Salopian and Downtonian divisions of the Silurian in its behaviour. While the latter are thickest to the north-west, and appear to thin steadily toward s the south -east, the Lower Old Red Sand­ stone behaves less simply. Tow ards the west, in South Wales, it apparently disappears by overlap against older rocks. In North Wales it is absent, and it seems likely that the old ridge against which the overlap took place ran from the neighbourhoo d of Carmarthen and Llandeilo in a general north -easterly di rection. The formation also probably disappears in a south-easterly direction, for on the eastern side of the F orest of Dean it is thinner than in Brecknockshire, and although there is ap pa rently a representati ve at P yrton Passage on the Severn , yet a little f arther south about T ortworth and in the Mendips it seems to be quite absent, the Old Red Sandstone of these districts p robably corresponding with the Upper Old Red of South Wales and the F orest of Dean, a subdivision which I think may ultimately be cla ssified with the Carboniferous. The Tortworth and Mendi p areas are perhaps part of the rid ge that separated the Devonian Sea from the shall ow dep ression in which the Old Red Sandstone was depos ited. The f acts seem to be best expla ined on the supposition that the Old Red Sand stone was deposited in a basin running in a north-easterl y direction j the beds on either side of this become thin and disappear , partly perhaps owing to marginal elevation and denudation. As to how f ar the basin extended to the south­ west and north-east we have little evide nce. The Old Red Sand­ stone appears to show no clear indication of thinning in these directions, and it must have continued for some distance to the north-east beyond the line of the Malvern and Abberley Hills, and the Forest of Wyre j for in this direction, where it either dis­ ap pear s beneath the Coal Measures, or is terminated by the great Malvern f ault, it is still thick. It seems highly probable that the absence of the formation over parts of the English Midlands is due, not to non-deposition, but to denudation, and that the origina l area of the " Welsh Lake " was much more extensive than 730 GEOLOGISTS' ASSOCIATION JUBILE.E VOLUM". might be gathered from the present distribution of the Sandstone. The Upper Old Red Sandstone again behaves differently. It is relatively thick around the Forest of Dean Coalfield, and around most of the South Wales Coalfield, in both of which areas it passes up into the Carboniferous. It is likewise thick in the Bristol Coalfield, though the base is not seen. In the Tortworth and Mendip areas it is fairly thick, but rests uncon­ formably on older rocks. When followed along the border of the South Wales Coalfield to the west, it shares in the overlap of the rest of the Old Red. When traced north across the Coalfield it decreases in thickness, and is apparently quite thin in the Clee Hills; and north and east of these hills it is absent. The behaviour of the Carboniferous is very similar. The various members thin, partly by overlap when followed from the southern margin of the South Wales Coalfield to the west, north­ west, north, or north-east; and towards the north the beds be­ come unconformable to the Old Red Sandstone. Their behaviour in these and other respects may be explained on the supposition that they have been deposited in a basin covering much of the area of the present Old Red Sandstone; this shallowed to the north-west, north, north-east, and east. Towards the margins the subsidence was slow, and the deposits thin. The sea occupied only the lower part of this basin. That the Clee Hills formed part of this basin is suggested by the occurrence of the well­ marked oolitic band found also in the Carboniferous Limestone of Bristol, South Wales, and the Forest of Dean. It is interesting to note that in this district, as in the Forest of Dean, the upper­ most part of the Carboniferous Limestone has evidently assumed the facies of the Millstone Grit,* a circumstance that agrees with the general behaviour of the Carboniferous on the assumption that it was deposited in a subsiding basin shallowing towards the north. This Old Carboniferous basin was probably separated from that of Coalbrookdale by a relatively narrow neck of the land; to the north of this the Carboniferous series thickens in a northerly direction. An interesting problem, similar to that of Woodbury Hill, is presented by the development and relation of the Carbon­ iferous of the Newent ann Forest of Dean Coalfields. A section (Plate XXIII, Fig. 2) drawn from the southern end of the Malverns across the Newent Coalfield and May Hill to the Forest of Dean Coalfield shows many noteworthy features. The considerable tilting of the older rocks, the folds of which have axes dipping east or north-east, and the disappearance towards the south of the Haffield Breccia, and of the Upper Bunter Sandstone. But the most remarkable circumstance is the great difference in the character, thickness, and disposition of the Car­ boniferous formation on the two sides of May Hill. In the • List of Works. No. 32. ~OC C EO I.. :\,; . .IU Bl I. E E \ ' 0 1.. I'U TE XX III.

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asurc,. 4. Co a l ~I,' S. Lower (Jld Red Sand st ou c. r z, Woo lho pc L imest o ne. 1(,. . vrr-h.enu . I' = F a ults. To / fiCC f ill:." 730 . THE MALVERN AND ABBERLEY HILLS. 731 Forest of Dean all the members of the Carboniferous are present as well as the Upper Old Red Sandstone. From personal in­ vestigations I give as provisional estimates the thickness of the three lower divisions on the eastern side of the Coalfield as follows : the Upper Old Red Sandstone, towards the north, oyer 400 feet; farther south, over 500 feet j the Carboniferous Lime­ stone, over 275 feet; farther south, perhaps 600 feet j the Mill­ stone Grit between Mitcheldean and Littledean, about 670 feet. These divisions, together, not less than 1,000 feet thick near the north-western corner of the coalfield have completely disap­ peareel in the Newent Coalfield, only four miles distant. The Coal Measures also, stated to be 2,765 feet thick in the Forest of Dean, are represented in the Newent Coalfield by a small thick­ ness only. Further, the Carboniferous strata in the Forest of Dean share in the considerahle folding of the Old Red Sand­ stone and Silurian of May Hill, while the Newent coals. inclined at low angles, must rest unconformably on various beels of the Old Red Sandstone. The explanation of these differences is, however, not perfectly simple. It involves a consideration, firstly, of the thinning of the Carboniferous strata of the Forest of Dean in the direction of Newent, perhaps combined with overlap j and, secondly, of intra-Carboniferous unconformities. According to the writer's mapping, the upper Old Red Sand­ stone, the Carboniferous Limestone, and the Millstone Grit of the eastern margin of the Forest of Dean basin all tend to thin very appreciably towards the north, and in this respect resemble the corresponding strata in the South Wales Coalfield. In the Clee Hills this northerly thinning is combined with overlap. It is possible, then, that the absence from Newent of the lower part of the series is partly due to the same causes, namely, deposition towards the margin of a geosyncline. the strata thinning in the direction of the land or of higher ground, and the lowest beds at the same time being overlapped owing to the general sub­ sidence that accompanied the folding. The distance, however, between the coalfields of Newent and the Forest of Dean is so short that it is difficult to believe that the whole of the differences can be due to these causes alone, which, moreover, do not account satisfactorily for the unconformity at the base of the Newent Coals. According to Mr. Kidston (No. 18), the true Lower and Middle Coal Measures of other parts of the British Islands appear to be missing from the Forest of Dean, the coals of which all belong to the Upper Coal Measures. It follows that, unless the measures that have not been detected are exceedingly thin, or are represented by the upper part of the Millstone Grit. there must be an unconformity at the base of the Coal Measures. Accordingly, the absence of the lower portion of the Carbon- 732 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME. iferous from Newent may be due in part to elevation and denudation of the district before the Coal Measures of the Forest of Dean were deposited. But the portion of the district that has undergone the greatest elevation is the anticline of May Hill, and from this it would be necessary to conclude that the Upper Old Red Sandstone, Carboniferous Limestone, and Millstone Grit of the Forest of Dean all must have been overstepped on the uiestern side of May Hill, that is to say within a distance for which the rate of overstep in the Forest of Dean appears to be insufficient. Much more importance must, I think, be attached to a second unconformity, namely, that at the base of the Newent Coals. It is obvious from the illustration (Plate XXIII, Fig. 2) that the de­ position of the Newent Coals was preceded by the movements that produced the Dymock syncline, the related anticlines of the Malvern and May Hill districts, and the syncline of the Forest of Dean. It follows that the Newent Coals are newer than those of the Forest of Dean, and that, were they present in that basin, they would rest unconformably on the Coal Measures, at any rate on the eastern side. It seems impossible to avoid the conclusion that all three factors just mentioned are jointly responsible for the differences between the two Coalfields in question, but the writer sees no reason to depart from the view formerly expressed that the folding of the Abberley Hills, the Malverns, the Woolhope Hills, May Hill, and the Forest of Dean coal-basin were connected phenomena, and took place chiefly in Coal Measure times. The writer (No. 24) was formerly disposed to recognise only one unconformity in the British Coal Measures, and since most of the evidence then available seemed to indicate that this was between the beds then generally recognised as Middle and Upper Coal Measures, it was argued that the great movements that gave rise to the Armorican chain and the associated coal-basins of Southern Britain took place chiefly during the interval be­ tween the deposition of these measures. But, thanks to the work of Messrs. Kidston, Cantrill, Gibson and Arber, the correlation of the British Coal Measures is now better understood, and greater precision has been given to the terms, Lower, Middle, and Upper Coal Measures, and it would now seem certain that the view then put forward was inadequate. It is, indeed, tolerably certain that there is more than one unconformity in the series owing to movements, some of which took place earlier, and some later, than the date indicated. Among the earlier movements was that which gave rise to the unconformitv at the base of the Whitehaven Sandstone, the lower part of which, according to "Mr. Arber (No. 30), is of Middle Coal Measure age. Here, too, we must mention the unconformity THE MALVERN AND ABBERLEY HILLS. 733 in the productive Coal Measures of Southern Scotland, an of which are stated by Mr. Kidston (No. 18) to belong to the Middle Coal Measures. There seems little reason to doubt that the unconformity beneath the Upper Coal Measures of Coal brookdale is a con­ tinuation of that below the same measures in the Forest of Wyre, as formerly implied by the writer. The movements that produced this unconformity were evidently also responsible for much of the tilting of the belt of Silurian strata south of Coal­ brookdale, a continuation of which to the south-west forms the western border of the Old Red Sandstone basin of South Shrop­ shire. This is well shown in Mr. Clarke's section through Madeley Court Colliery (No. 26, at p. 88). At a still later date took place the great folding movements that were chiefly responsible for the production of the Armorican range of Southern Britain and its offshoots in the Midlands. The higher Coal Measures of Somerset and South Wales, and the greater part of the higher Coal Measures of Wyre Forest, and all the Measures of the Forest of Dean appear to be Upper Coal Measures. These measures all participate in the folding of the Trimpley anticline, the Abberley Hills, May Hill, and' the coal-basins of the Forest of Dean, Somerset and South "Vales. These movements, accordingly, took place after the de-position of the Upper Coal Measures, which is the upper part of the series that Mr. Arber (No. 34) regards as intermediate between the Westphalian and Stephanian of the Continent. According to the same observer, no Stephanian beds occur in Somerset or South Wales. On the other hand, the movements took place before the deposition of the Newent and Woodbury Hill coals. The precise horizon of these is as yet undetermined j they may belong either to the Upper Coal Measures or to the Stephanian. But the conclusion may be drawn that the Hercvnian movements in Southern Britain took place either in Stephanian times or during the transitional period between the Stephanian and the preceding Westphalian. The corresponding movements on the Continent are understood to have taken place in the interval between the Westphalian and Stephanian. Taking all the facts into consideration, it seems probable that the Carboniferous beds of the district between the Forest of Dean and Wyre Forest were deposited near the margin of a geosyncline, that of South Wales and Bristol, itself situated to the north of the main Armorican range; that the Clee Hill district formed part of this basin, and that this portion of the geosyncline nearly met a second geosyncline in which the Coals of Coalbrookdale were deposited; that in places the margin of 1jhe southern geosyncline underwent considerable crumbling and faulting, especially late in Coal Measure times, and that 734 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME. the Malvern-s-Abberley Range, May Hill, and the associated basins were largely the result of this folding. Towards the margin of the geosyncline subsidence was less, and the Car­ boniferous deposits were thinner, the higher beds overlapped the lower, and the subsidence was interrupted or followed by eleva­ tion, which gave rise to unconformities not detected in the deeper parts of the syncline. As to the original extent of the mountain land of which the Abberley and Malvern Hills probably formed the foot-hills, we are still imperfectly informed, since much of the evidence needed lies buried beneath the Mesozoic deposits of the Midlands. But the progressive southerly thinning and overlap of the Coal Measures in South Staffordshire and Warwickshire suggest an extension of high ground far to the east of the Malverns. The Malvern and Abberley ridges appear to have been shortlived, for the folds were so extensively denuded during the Coal Measure times that the level was reduced to that of the plane on which the highest Coal Measures were deposited. Farther east the" Mercian Highlands" seem either to have lasted longer, or to have under­ gone fresh elevation, for the great screes of the Midland " Permian" strongly suggest mountainous land in late Car­ boniferous or early Permian times, not far to the south or south­ east of their outcrop. Further movements in the western Midlands evidently took place before the deposition of the Haffield Breccia, for this rests with discordance, not only on much older rocks, but on the Coal Measures, This is inferred from the appearance farther north, between the two, of a considerable thickness of other beds, the Trappoid Breccia thus becoming widely separated from the workable Coal Measures. The lower portion of this inter­ vening series-a part of the "Transition Measures," and the overlying Keele Beds-Mr. Arber (No. 34) would group into a series intermediate between the Westphalian and Stephanian. But, in the absence of palreontological evidence, the age of the upper part and of the overlying Breccia is still in doubt. Near Nottingham* the true Permian beds rest unconformably partly on the Keele beds (Upper Coal Measures), and partly on the underlying Transition series. But these overlying Permians appear to represent little, if anything, more than the Zechstein of the Continent, and it is therefore doubtful whether the upper part of the Midland" Permian," including the Breccia. are to be correlated with the Stephanian or uppermost Coal Measures, or with the Rothliegende or Lower Permian. According to Mr. King (No. 22) the Trappoid Breccia of the Midlands is thickest and coarsest to the south, and thins and passes into sandstone to the north. This clearly indicates a southern source. The materials have not been so closely studied * List of Works, No. 3I. THE MA LV E RN AND ABBERLE¥ HILLS. 735 as those of the und erl ying " Middl e Permian." The R affi eld Breccia of the Abberley Rills, according to the writer, includes many fragments of fossiliferous May H 'ill Sandstone (found al so, according to Mr. King, in the Warley, Enville, Clent, Stour Valley, and Northfield districts) j also many fr agments of various coloured sands tones, grits, conglomerates, agg lomer­ ates and tuffs, The materials are generally subangular, and blocks range up to 29 inches or more in length. In pl aces much of the material may have been derived f rom the destruction of the May H ill Sandstone, but in other places ashy materi als, pro- bably of Archsean age, predominate. _ The beds of NIr. Wickham King's " Middle Permian " in general become coarser to the south-south-east, and their source was probably the same as that which supplied the " Upper Per­ mian." The pebbles include hornstones, grey and purple fels­ pa thic grits, coarse and fine tuffs, and agglomerates, which are presumably of Archrean age; quartzite like that of the Lower Cambrian of the Midlands; fossiliferous sandstone resemblin g th at of the May Hill format ion of the Midlands j limestones resembling the tVoolhope and Wenlock Limestones j and dolo­ miti c Carboniferous Lim estone. But there are apparently no rocks of Ordovician or Old Red Sandstone age. T his is an assemblage that one might expect from a district such as the E nglish Midlands. The Permian breccias have long been regarded by Midl and geologists as the more or less modified screes of -the mountains of the old " Mercian Highl ands." We may reasonably picture these highlands during late Carboniferous or early P ermian times as extending from the districts of Wyre F orest, Abberley, Malvern and May Hill in an easterl y direction over th e southern part s of the Midland s, and as pa rtly, perhaps largely , composed of rocks of the type of the Uriconian, Lower Cambrian, Silurian and Carboniferous Limestone now seen here and there within the area. After the deposition of the R affield Breccia further movements, probably accompanied and succeeded by great denudation, took p lace. The old mountains were levelled down to a tolerably smooth surface , on which the various di visions of the T rias were deposited. This surface, as is maintained by Mr. Jukes-Browne in his excellent treatment of the subject (No. 14), apparently ha d a general northerly or nort h-westerly slope, as is indicated by the successive overl ap of different members of the T rias in t he reverse directions. Much may be said in fa vour of the view that the Trias of the E nglish Midlands is a terrestrial formation, and to thi s view the writer subscribes. During its deposition the Midl ands, including the Malvern-Abberley H ills, probab ly formed a gently undul atin g plain, which gradually rose to the south and south-east, a tract, in places r aried by hill s, 736 GEOLOGISTS' AS SOCIATION JUBILEE VOLUME. such as would give rise to the Bunter breccias (screes) of Wor­ cestershire and Shropshire. As the lower grounds became occupied by debris, the more elevated became reduced in height, and the hilly ground gradu­ ally retreated to the south and south-east. Finally the most northerly situated ridges of the Armorican chain in the south shared the fate of the rest, and became buried by the highest division of the Trias-the Keuper marls, which rest directly on the older rocks. The history, however, was apparently not one of mere denudation and deposition. Movements during the Trias are indicated by the unconformities in the formation itself. The behaviour of the component beds may, I think, be largely explained if we suppose a gradual sinking of the whole tract, depression taking place most rapidly to the north-west, this depression being interrupted by occasional cessation or reversals of the movements towards the south. Finally, how­ ever, the low-lying plains were gradually converted into the sea bed of the Rhtetic period. As to the later history of the Malvern area we have little precise information. At some subsequent period or periods folding, generally of a gentle character, together with considerable fault­ ing, affected the Trias and Rheetic beds. All along the eastern side of the Malvern and Abberley Hills the country sank along a great undulating north and south fault line, and here and there along faults crossing the site of the present range. It was possibly at the same time that other of the Paleeozoic areas of the Midlands became defined by folding and faulting in the same way, as, for example, the South Staffordshire Coalfield. Here and there, as near Ankerdine, the Trias underwent greater disturbances. In general the Triassic beds dip gently away from the Malvern and Abberley Hills, indicating a post-Triassic rise of the district, or a sagging down of the adjoining areas. Ultimately the upper­ most Coal Measures, the Haffield Breccia, and the Trias, and any later rocks were removed by denudation from the greater part of the area of the present hills. Of the time at which the latter movements took place we have little evidence, but the sharp way in which the hills rise up from the plain along the fault line suggests a moderately late date. The fault, indeed, may well be of Tertiary age. A recent earthquake shock, traced by Mr. Davison (No. 33) to the Malvern fault, suggests that movements still occur along this line. In conclusion, I must cordially thank Mr. A. J. Jukes­ Browne, who has read through the MS. of this article, and made valuable criticisms j and Messrs. P. Lake and F. A. Bather for information as to the trilobites and echinodermata of the Silurian rocks of the district. THE MA LVERN AND ABBERLEY HILLS. 737

NOTE ON A B ORI NG AT C OL WALL. I am ind ebted to Mr. Wickham, of Colwall, for pa rticulars as to a boring made at Colwall by Messrs. Schweppes in search of water. The boring was commenced about September, 189 1, on the site of the mineral water f actory near the rail way station. Owing to the leath ery consistence of the marl s met with, slow progress was mad e, and the boring continued uninterruptedly for nearl y four yea rs. T he chisel was used up to perhaps 300 or 500 fee t, then the iron-circle, and beyond about 1 ,000 feet the diamond drill. The boring ceased at 1 , 240 feet. The materials tr aversed were as follows : J. Detritus 20 to 30 feet thick consisting of angular stones from various Silurian formations ranging from the May H ill Sandstone to the Ludlow, and some from the Archrean , 2. Purplish marls, here and there interbedded with grey or red sandstones. The marl s were tested with hydrochloric acid, but showed no effervescence. They ceased at 1,160 feet. 3. Hard crystalline limestone with fossi ls, extending down to the bottom of the boring. Mr. Wickham considers this rock to be the Aymestry Limestone. The dip of the beds is stated to be about 45° in a westerly direction. No traces of beds resembling the Ludlow Shales were detected. No water was obtained until the limestone was reached , when it came suddenly, and has since continued to flow out at about the rate of a pint per minute. It pro ved to contain an appre­ ciable quantity of salt . NI r. Beecham informed me that Professor A. H. Green visited the scene of the boring when a depth of goo feet had been reached without obta ining water, and thought that water would be found at a dep th of about 1 , 2 5 0 feet. The site of the boring is well within the limits of the OILI Red Sandstone, and the upper portion of the " marl " must belong to this formati on. But in a core of chocola te-coloured micaceous sandstone with green blotches, taken from a depth of 1, 1 20 feet, and now preserved in the Geologica l Museum at Oxford, Lingula cornea is abundant, a fossil tolerably common in the Ledbury Beds, but not in the overlying Old Red Sand ­ stone. The colour pr acticall y forbids the notion that these lowest" marls" belong to the Downton Sandstone. It foll ows, then, that the lower part of the " marls," occupying not less than 40 feet of the boring, belong to the Ledbury Beds. T he absence of the Upper Ludlow Shales, and presumably of the Downton Sandstone, is probab ly explained by the assumption that the Ledbury Beds are fau lted against the Aymestry Lime­ stone. Vertical Up per Lud low Shales, however, are seen in the 49 738 GEOLOGISTS' ASSOCIATION JUBILEE VOLUME. scarp to the east-south-east, some 320 yards away from the well. The fault presumably crops out to the east of them, pro­ bably at the foot of the scarp. A fault between the harder Ludlow beds and the softer Old Red and Passage beds would explain the known irregularities* in the thickness of the Upper Ludlow Shales at their outcrop on the western side of the Ledbury Hills. I have observed similar irregularities about the junction of the Silurian and Old Red Sandstone in the May Hill and Newnham districts.

LIST OF WORKS TO WHICH REFERENCE IS MADE IN THE TEXT.

1. Murchison, Sir R. 1., "Silurian System." ,839. 2. Phillips, J., Mag. and Journ. of Science, vol. xxi, ,842. 3· ---- l'dem. Geoi. Suru, vol. ii, ,848. 4· Murchison, Sir R. 1., "Siluria," ,854. 5· Symonds, W..~., and Lambert, A., Quart. Journ. Geol, Soc., vol. xvii, ,86" p. 152. 6. Hall, H. B., Ibid., vol. xxi, ,865, p. 72. 7· Symonds, W. S., "Records of the Rocks." 1872. 8. Callaway, C., Geot. Mag., dec. 2, vol. vi, ,879, p. '42. 9· Quart. Journ. Geoi. Soc., vol. xxxvi, ,8150, p. 536. 10. tu«; vol. xliii, 1887, p. 525. II. Rutley, F., Ibid., vol. xliii, ,887, p. 481. 12. Teall, J. J. H., "British Petrography," ,887, 13· Callaway, C., Quart. Journ. Geol, Soc.; vol. xlv, ,889, p. 475. '4. Jukes-Browne, A. J., "Building of the British Isles." 1892. '5· Piper, G. H., Trans. WoolilOpeCtub, r893' 16. Callaway, C., Quart. Journ. Cieot. Soc., vol. xlix, 1893, p. 398. 17· Jones, D., Trans. Fed. Lnst : Min. Eng., 1894. ,8. Kidston, R., Proc. Roy. Phys. Soc. Edinb., vol. xii, r894' '9· Green, A. H., Quart. Journ. Geai, Soc., vol. li, ,895, p. I. 20. Acland, H. D., Ibid., vol. liv, '898, p. 556. 21. Lapworth, C., "Sketch of the Geology of the Birmingham District." Proc, Ceol. Assoc., vol. xv, 1898, p. 3r3. 22. King, W., Quart. Journ. Oeol, Soc., vol. lv, ,899, p. 97. 23· Groom, T., Ibid., vel. lv, [899, p. '29' 24· ----- Ibid.; vol. ivi, '900, p. '38. 25· Chapman, F., Ibid., vol. lvi, '900, p. 257. 26. Clarke, W. J., tu«, vol. lvii, '90', p. 86. 27· Groom, T., Ibid., vol. Ivii, '90r, p. '56. 28. ----- Ibid., vol, lviii, 'g02, p. 8g. 29· Harker, A., "Petrology for Students." '902. 30 Arber, E. A. N., Quart. ]ourn. Ceot. Soc., vol. Iix, r903, p. I. 31. Gibson, W., "Geology of the North Staffordshire Coalfield." Mem. Ceot. Surv. 'gas. 32 • Vaughan, A., Quart. Jottrn. Ceol. Soc., vol. lxi, 1905, p. 181 33· Davison, C., Geol, 11lag., dec. 5., vel. v, 'g08, p. 296. 34· Arber, E. A. N., Quart. Jottrn. Oeol, Soc., vol. lxv, 'gog, p. 21.

* List of Works , NO.3.