Stratigraphy and Fauna of Easton Bavents Cliffs

157

FOSSIL VOLES

fourth re-entrant on the outer side. The roots cannot be seen from the side as the lower portion of the tooth is embedded in a fragment of bone but the end of the posterior root can be seen from below.

FIG. 3.—The inner side of the first right upper molar from Easton Bavents. The anterior root is complete and well developed : the two others have been broken but there are clear indications of both.

FIG. 4.—The inner side and base of the second right upper molar from Easton Bavents. T h e posterior root is more or less complete, another, and that nearly closed, can be seen. C.

STRATIGRAPHY AND FAUNA OF THE EASTON BAVENTS CLIFF SECTIONS, NEAR SOUTHWOLD, SUFFOLK BY

G.

P.

LARWOOD,

B.SC.,

F.G.S.

AND A .

J.

MARTIN.

IN 1952, Mr. R. A. Long of Lowestoft drew attention to the recent erosion of the cliffs at Easton Bavents, Suffolk, and it was realised that an excellent opportunity was provided to re-examine the entire sections from Southwold to Easton Broad, last fully described between 1875 and 1878 by W. Whitaker. Accordingly detailed observations of the exposures were made on a number of occasions in September, 1952, and March, 1953. T h e present paper is an attempt to describe the observed sections in detail and to resolve some of the apparently conflicting views expressed by previous workers as to the true limits and origin of each division within the succession exposed.

DESCRIPTION

OF T H E

SECTIONS

(See diagram facing page 160)

It was found that the beds exposed in the cliff sections could be grouped into three major units, the uppermost being the more variable. T h e grouping adopted was as follows :— 3.—Uppermost sands with gravels.

2.—Variable blue-grey clay unit.

1.—Basal sands with or without shells and shell beds.

T h e lithology of each unit is described in the order of deposition.

158 UNIT

STRATIGRAPHY AND FAUNA OF EASTON BAVENTS 1.

This lowest member of the succession was first exposed at the base of the cliffs just over a quarter of a mile north of Southend Warren (G.R. 515779) where it consisted of current-bedded sands. Further north, immediately east of the northern-most house on the clifftop (G.R. 517784), these sands were seen to have expanded to an exposed 10 feet and were light yellow-brown in colour, current-bedded and ironstained with occasional gravel seams of small, rounded, flint pebbles. 500 yards south of Easton Broad (G.R. 518787) only 5 feet of this unit was exposed, and consisted of sands with scattered shells and two definite shell beds (See PI. I fig. 1). At the base of the cliff at this point, 1 foot 6 inches of light brown, fine quartz-sand was exposed, overlain by a lower shellbed of massed Teilina spp., which were very common, with other less numerous genera set in a typically coarse quartz-sand matrix. Above this a somewhat stiff, clayey, yellowbrown sand was developed beneath an upper shellbed. Teilina spp. occurred frequently in this clayey-sand, many specimens being complete with their valves united and with a tendency to be concentrated in distinct bands. T h e upper shellbed, 1 foot 6 inches thick, had at its base a concentration of black, subangular flint pebbles—these occurred again a little above the middle of the bed. T h e shell remains were more comminuted than in the lower shellbed, and in this respect showed similarity with the shell material in the Norwich Crag of the Norwich area. T h e matrix was of abraded subangular white and colourless quartz grains with some quartz pebbles. Above the upper shellbed 1 foot of fine light yellow-brown, unfossiliferous sand occurred.

Throughout the length of the exposure of the beds which composed this unit, Variation in thickness was observed, but the lithological types were constant. Progressively northwards this shelly facies died out, and the cliffs diminished in height. Immediately south of Easton Broad 5 feet of unfossiliferous light-brown sand was the last seen of this unit.

UNIT

2.

T h e second major unit in the cliff sections first appeared above beach level at just over a quarter of a mile north of Southend Warren where it was seen as a clayey deposit. This was lightbrown in colour, and in parts somewhat sandy, but generally consisted of a buttery clay with small black flecks throughout.

T h e latter were possibly a secondary iron-staining feature only.

U p to 4 feet thick at this point, the clay thinned slightly northwards expanding again to a 10 feet thickness of interstratified grey, sandy-clays and yellow brown sands, but with clay always dominant.

T h e clay thus appeared as an increasingly distinct unit northwards.

At the point where the underlying shell-beds were best developed,

STRATIGRAPHY AND FAUNA OF EASTON BAVENTS

159

the clay was up to 5 feet thick only, but was a blue-grey, homogeneous, slightly silty and tenacious deposit, weathering brown on the surface. Here it was a clearly defined unit having an abrupt junction with the sands below. Again, as with the underlying beds, the clay varied in thickness and in this case also in lithology.

Thus only fifteen yards to the north it had diminished to a bed, 2 feet 6 inches thick, of clay with occasional sand lenses. Furthermore, just to the south of Easton Broad it became more loamy and its lower limit less definite. The loamy-clay and the unfossiliferous sands beneath filled the entire section at this northern end where the cliffs are only ten feet high (G.R. 519791) and the section was terminated by Easton Broad.

UNIT

3.

Finally, the uppermost major division, which was lithologically the most variable of the three, overlay the clay sequence and, south of G.R. 515779, filled the entire cliff section. Where the cliffs began, and northward from Southend Warren (G.R. 514775), this unit was seen as a variable sequence of gravels and sands.

At the base of the cliffs 12 to 15 feet of fine current-bedded yellow sands were exposed. These were overlain by 6 feet of very gravelly sand, again current-bedded and the gravel composed entirely of flint pebbles. This was capped by 2 feet of currentbedded sands without gravel. Northwards, a series of thickening white sands was developed at the top of the section—these were less definitely current-bedded and contained few or no gravel seams. Irregularly graded flint-gravel seams occurred locally in the white sands, and iron-staining and cementation became marked in the underlying gravelly sequence. Further north, (G.R. 514776), channelling was evident within the white sands at the top of the section. One of the largest of these Channels— over 60 feet wide and up to 5 feet 6 inches deep—was seen to be lined with a thin basal gravel, the remainder being infilled by fine white sands similar to those into which the Channels were cut (See PI. I fig. 2). Some current-bedding was observed in the sands infilling the Channels. T h e channelling was developed for some distance northwards, the deepest being cut down 12 feet into the white sands. Flint-gravel in one Channel contained occasional white quartz pebbles. T h e sandy-gravels, underlying the white sands, persisted but diminished in thickness until, at G.R. 515779, the top white sands filled most of the cliff section, and the only gravels observed were those confined to the bases of the infilled-channels in the white sands. Marked channelling ceased about 8 feet above the top of the yellowy red-brown sands immediately overlying the clay unit previously described. With the clay unit increasing in thickness, and rising in the cliff section, and with a similar thickening in the sands underlying the clay, the uppermost unit was reduced to a series 4 feet thick. Here

160

STRATIGRAPHY AND FAUNA OF EASTON BAVENTS

also, at G.R. 517784, the lithology of the unit changed and is better described as a loamy clay series with prominent pockets of sands and gravels. This was readily distinguishable from the main clay unit in the succession. This clayey facies of the upper unit was seen to be a local development only, and northwards there was a rapid lateral transition to an illgraded flint-gravel and sands with marked gravel seams of variable thickness—the whole being 12 feet thick. Beyond this the unit had been thinned by surface erosion and was not present at the top of the low cliff section exposed just to the south of Easton Broad.

The observed variations in the lithology and thickness of each major member of the section are shown on the accompanying diagram.

STRATIGRAPHY

OF THE

SECTIONS

The threefold division of the whole cliff section established

by W. Whitaker (13) is still apparent. In the present description these three units are recognised but modified and interpreted differently. The grouping proposed maintains the three major units as follows. At the base is a series of sands with occasional gravels, and sands with or without shells and shellbeds ; that is, all the exposed members beneath a definite clay horizon. Above this the second major unit consists of a clay horizon only. Every other lithological type developed above this definite clay horizon togetherconstitutesthe third major unit of the succession—largely sands and gravels.

One of the earliest descriptions of the Easton Bavents cliff sections was made by Prestwich in 1849, and the locality was mentioned again by the same author in 1871 (10). On both occasions Prestwich seems to have been undecided on a final nomenclature for the sections suggesting that the so-called " Chillesford " deposits were either equivalent to the " Mammaliferous Crag of Norwich " or that the beds in question belonged to a period one stage more recent than the Mammaliferous Crag.

In 1871 he interpreted the succession in the Easton Bavents cliffs as :— 3 —Westleton Beds. 2.—Chillesford Clay. 1.—Chillesford Sands.

At the same time, he thought it possible that the " Chillesford Sands " might be the equivalent of the Upper Norwich Crag.

In 1863, Lyell (9) referred to the Chillesford type section as being the southernmost point to which " the marine beds of the Norwich Crag have been traced." This is, presumably, a reference to the shelly-series developed at Chillesford. S. V. Wood, on the other hand (1865), suggested that the Chillesford Beds were a local member of the division of the glacial series

STRATIGRAPHY

A N D FAUNA OF EASTON BAVENTS

161

Avhich he termed " Middle Drift." He referred to the Chillesford Beds as passing up " without the least break into the Middle Drift," and as " evidently part of that division."

The Rev. O. Fisher, writing in 1866 (3)—specifically on the relationship between the Norwich Crag and the Chillesford Clay— mentioned the occurrence in the clay at Easton Bavents of a lenticular patch of sand containing marine shells. He concluded that although " the character of the deposit might otherwise have led one to suppose that it was lacustrine " that there was—on the above evidence—" no doubt about the Chillesford Clay (at Easton Bavents) being a marine deposit."

Between 1875 and 1878 W. Whitaker (13), in the Geological •Survey Memoir for the district, produced the first and only complete account of the cliff sections from Southwold to Easton Broad.

In this he recognised three major divisions, at the base " Crag " overlain by " Chillesford Beds " with, at the top, a " Pebbly Series." His middle unit included laminated clays and sands.

Nowhere, however, did he give a more definite name to his basal •unit other than " Crag," but his term " Chillesford B e d s " apparently included more than the clay itself, and the " Pebbly Series" represented part of what Prestwich had termed the " Westleton Beds."

H. B. Woodward, in his Geological Congress Report of 1888 (15), attempted to correlate the already confused nomenclature attached to the " Norwich Crag Series," and referred to this Series " as having the following local divisions :— 3 —Bure Valley Beds—pebbly sands and pebble beds. j , /Chillesford Clay.

2.—Chillesford B e d s < [ c h i l l e s f o r d g a n d w i t h s h e ll-bed.

1.—Fluvio-marine Crag with shelly-sands and stone bed ( = t h e Upper part of the Red Crag).

T h u s the Easton Bavents succession could be considered as representing part of Woodward's two upper major units 2 and 3.

Blake, in 1890 (1), apparently limited the term " Chillesford Beds " to the clay unit and regarded the underlying shelly sands as part of the Norwich Crag Series. Furthermore, he recognised his " Chillesford Clay " as extending from Easton Bavents to as far north as Corton.

Between 1877 and 1908 F. W. Harmer was writing extensively on the Pliocene and Pleistocene deposits of East Anglia, and during this time developed the theory of the estuarine origin of the Chillesford Beds (5, 6, 7, 8). Nowhere does he specifically mention Chillesford Beds in the Easton Bavents sections, though his well-known maps show the sinuous course of the suggested estuary of the proto-Rhine cutting across the line of the present-day ccast just to the south of Southwold and swinging westward

162

STRATIGRAPHY AND FAUNA OF EASTON

BAVENTS

again north of Easton Bavents. It is thus fairly obvious that hc intended the clay unit at Easton Bavents to be considered as part of his estuarine deposits. T h e 1896 paper on the Pliocene deposits of Holland and their relation to the English Crag gives a particularly clear and careful account of his theory (5). More recently, in 1935, J. D. Solomon (12) has suggested, on very definite evidence based on heavy mineral analysis, that the clay unit in the Easton Bavents cliff sections is " certainly not equivalent to the Chillesford Beds of the type locality."

1t is apparent that the limits of the Chillesford Beds were poorly defined and, as far as the Easton Bavents sequence is concerned, it is now proposed to refer to the sequence as follows :— 3.—Sand and Gravels. 2.—Blue-grey clay. 1—Norwich Crag Sands with Shell-beds.

For various reasons the basal member may be considered as part of the Norwich Crag shelly facies. Ecologically there is nothing that is inconsistent with normal, littoral, shallow water marine deposits : the contained shell material is largely fragmental and the matrix is composed of pebbles and relatively coarse sand grains and is not particularly well-graded. Current-bedding is well developed. All these features are closely similar to those displayed in the Norwich Crag of the type area, also there is little difference between the faunas of the two areas. The possibility that the major part of the shell material in the beds at Easton Bavents is derived is largely ruled out by their natural and faunal content. Apart from the obviously derived fish remains, no material is markedly rolled and although much of the shell material is comminuted it very probably represents accumulation of relatively fragile indigenous forms under currentdisturbed conditions. Some forms, in fact, with valves united, are preserved apparently in the position of growth. Statistical study of the East Anglian Crag faunas from the Coralline Crag to the Cromer Forest Bed, made by P. G . H . Boswell in 1931 (2), showed an increasing number of Arctic forms in the later Crags and a corresponding decrease in the number of Mediterranean forms. In this series the least marked change in faunal content is between the Norwich Crag and the succeeding " Chillesford Crag." Of the now living species represented in the Norwich Crag 11% were given as Arctic forms and 9% as Mediterranean forms, whilst in the " Chillesford C r a g " 10% were given as Arctic forms and 3% as Mediterranean forms. The difference between these two Crag faunas being so small it would seem justifiable to regard the lowest unit at Easton Bavents as an actual shallow water facies of the top part of the Norwich Crag. T h i s is the case even if the shelly Crag at Easton Bavents should actually fall within the Statistical limit laid down for the " Chillesford Crag " ; for it can be considered as the top part of the Norwich

STRATIGRAPHY AND FAUNA OF EASTON BAVENTS

163

Crag deposited under only slightly colder conditions than those which prevailed during the deposition of the main mass of the Norwich Crag.

The second major unit, at present recognised in the Easton Bavents sections, is the clay member which Harmer regarded as part of his " Chilesford Beds." A problem arises from the concept of the Chilesford Beds as the deposits of an estuary of the proto-Rhineflowingnorth from the ancient Ardennes massif.

Harmer first postulated this theory on the evidence of the type section at Chilesford where frequent minute micaflakesoccur in the clayey series. He suggested that this mica was derived from the above mentioned massif. There is no evidence of mica concentration in the clay at Easton Bavents, and it may well be that the clay is essentialy a marine deposit; unfortunately there is, at present, no preserved fauna to check this. In the past a marine fauna has definitely been found in the clay. Prestwich recorded the presence of many marine forms in what he termed the " Chillesford Clay " of Easton Bavents. In the same paper he also listed the marine forms of the " Crag " for the same locality. It would therefore appear that a definitely marine fauna has been obtained from the clay horizon itself; for, as the fauna of the shell-beds is listed separately, the term " Chilesford Clay " cannot refer to the clay plus an extended series of sands with shells but must refer to the clay alone. Prestwich's faunal list for the " Chilesford Clay " of Easton Bavents is as follows :â&#x20AC;&#x201D; " Astarte compressa, Cardita scalaris, Cardium edule, Corbu Cyprina islandica, Leda oblongoides, Lucina borealis, Mactra Mactra subtruncata, Mytilus educis, Nucula cobboldiae, Te lata, Teilina obliqtia, Buccinum undatum, I.ittorina littorea, Na cirriformis, Purpura lapillus, Turritella communis."

The presence of so many marine forms is hardly consistent with the above mentioned concept of the derivation of the clay and its deposition in estuarine conditions, but at the same time it does not compare well with the present totally unfossiliferous nature of the clay in the Easton Bavents sections. However, Fisherâ&#x20AC;&#x201D;in 1866â&#x20AC;&#x201D;also recorded a marine fauna from an included lenticle of sand in the same clay. F. W. Harmer, having suggested estuarine conditions for the deposition of the Chilesford Clay, elaborated on this view in a subsequent paper (6). He referred to the type section near Chilesford Church and mentioned a fossiliferous sand underlying the Chilesford Clay in this locality.

He stated that " there is no other deposit at present exposed where precisely the same group of shells is found." He then listed " the most characteristic of these " as, " Natica catena, Leda oblongoides, Leda lanceolata, Turritella communis, N cobboldiae, Nucula tenuis, Cardium edule, Cardium groenla Mactra ovalis, Teilina lata, Teilina obliqua and Mya truncata."

164

STRATIGRAPHY AND FAUNA OF EASTON

BAVENTS

Reference was also made to the way in which " many of the bivalves occur with both valves adherent." He suggested that this essentially marine fauna did " not wholly represent an undisturbed sea-bottom " and that " most of the shells appear to have been brought up by the scour of the estuarine tides, having been buried while living, or soon after death, in the tidal sediment."

At Easton Bavents, as already mentioned, there seems to be no reason for supposing that the shell beds beneath the clay are drifted or derived. Furthermore, the recorded marine fauna for the clay does not seem to be consistent with the theory of its being a strictly estuarine deposit. With regard to the derivation of the sediment composing the clay, J. D. Solomon's more recent heavy mineral analysis in which he found it to be " fĂźll of Scandinavian minerals " excludes the possibility of a southerly derivation.

In fact, Solomon concluded that the clay at Easton Bavents was not equivalent to the Chillesford Beds of the type locality. Thus, on the evidence of the recorded fauna and the contained Scandinavian minerals, it would seem that the clay is essentially a marine deposit, which was laid down under relatively open-water conditions. However, in view of Harmer's contention that true marine forms can be found in numbers in estuarine deposits, it is difficult to envisage conditions other than at least in part estuarine as an environment for the accumulation of the clay.

Even though the presence of true marine forms need not exclude a truly estuarine environment of deposition for the clay, the presence of a suite of Scandinavian minerals does suggest a more -open communication northwards than Harmer indicated for his estuarine conditions. Accepting Solomon's recognition of such a suite of Scandinavian minerals, it would seem necessary to limit Harmer's somewhat confined estuary to at least south of the present position of Southwold, and to envisage to the north of this point, an ill-defined " estuary " with wide connections with the open sea northwards. For the present, therefore, it is suggested that the clay at Easton Bavents was deposited under such a relatively open-water environment.

The upper series of channelled sands and gravels, which at present is considered as a single unit and includes everything above the clay in the Easton Bavents sections, may be regarded as a waterlain deposit. In the past great uncertainty has been expressed as to the relative age, and even origin, of this unit. Clement Reid, in his " Pliocene Deposits of Great Britain," followed Whitaker in referring to the pebble gravels of this upper unit as part of the " Pebbly Series." Like Whitaker, he used this indefinite term for " the large residuum which remains after all deposits of determinable age have been separated." In 1935, Solomon tentatively referred the coarse sands and pebblygravels to the " Mid-Glacial Sands " and stated that they contained " the usual Pebble Gravel mineral assemblage." He went on

STRATIGRAPHY

A N D FAUNA

OF EASTON

BAVENTS

165

to say that " in no instance " do they " contain any material which could be considered as outwash corresponding to the Chalky Boulder Clay," and he thought that both microscopic and macroscopic lithological criteria disproved the age of the gravels as being equivalent to that of the Chalky Boulder Clay.

He assigned the deposit to his " Westleton series of sands and gravels" which he regarded as a widespread marine deposit contemporary with a glacial phase which brought the Scandinavian ice to the coast of Norfolk. From the Easton Bavents cliff sections alone, there is little evidence to decide the true age and Position of the deposit, but it was certainly laid down in some depth of water.

Thus the present conclusion is that the succession exposed in the Easton Bavents cliff section is as follows :— 3.—Pebbly Series—unfossiliferous water-lain sands and gravels.

2.—Chillesford Clay.

1.—Norwich Crag—sands and shellbeds.

To avoid confusion the names used by previous authors are retained, but the term " Chillesford " is applied in a strictly limited sense to the clay unit alone.

T H E SHELL BEDS AND FAUNA OF T H E NORWICH CRAG AT EASTON BAVENTS In general appearance the shellbeds in the sands of the lower unit at Easton Bavents are very similar to the shelly facies of the Norwich Crag in the Norwich district. There are, however, certain noteworthy local features, and these were best exposed at G.R. 518787.

The Upper Shell Bed (1 foot 6 inches thick) was composed largely of comminuted shell material, although whole specimens were not infrequent. There was also a relatively high proportion of black and brown, ill-graded, sub-angular, flint pebbles, and— concentrated at the base—a markedly pebbly seam with phosphatic nodules, fragments of worn phosphatised mammalian bones, and much rolled remains of Platax woodwardi. These heavily mineralised remains are almost certainly derived from an earlier deposit.

Most of the mammalian bones are unworn and well preserved. The preservation and composition of the fauna contained in the sand which intervenes between the Upper and Lower Shell Beds is distinct and different from the contained fauna of those beds. In the Lower Shell Bed many of the shells present are unbroken specimens.

Teilina obliqua and Teilina praetenuis are very common and particularly well preserved—several were noted with both valves united. Shell material is in excess of matrix and numerous complete

166

STRATIGRAPHY AND FAUNA OF EASTON BAVENTS

valves of Cyprina islandica are present, Yoldia oblongoides is also a frequent form. The flint pebbles contained in this shell-bed were found to be of two main grades—the larger between 0.25 and 0.5 inches in diameter being quite well rounded, and the smaller, all well under 0.25 inches in diameter, being markedly angular. Occasional pebbles of hardened white chalk and of quartzite are present. Comparing the two shell beds it is seen that, in both, shell material is in excess of matrix, but fewer flint pebbles are contained in the upper than in the lower shell bed.

Also, shell material in the Upper bed is more comminuted, whilst the proportion of united and whole valves to fragmentary material is greater in the lower than in the upper bed.

In both beds complete and fragmentary valves of the larger lamellibranches—such as Cyprina islandica—are often worn, as are the remains of some of the smaller gastropods present. The majority of the shell fragments tend to lie with their long axes horizontal, although inevitably in such shell sands this can only be a generalisation.

Lamellibranchs are predominant and are largely of the active free-moving forms, being mainly represented in the heterodont sub-orders Cardiacea, Astartacea, Mactracea and Tellinacea. No one sub-order, genus or species is dominant, with the exception of the Tellinacea. There is a general lack of gastropods in relation to the bulk of the fauna, particularly those strengthened forms common to areas of strong wave action.

Nucella lapillus, for example, occurs quite infrequently. Many specimens of juvenile lamellibranchs are present in both shellbeds.

Fragmentary remains of large mammals also occur in both shellbeds. A large fragment of Elephas limb-bone was found in the centre of the lower shellbed. Fragments of Cervus sp., metacarpal and vertebrae, and teeth, skull fragments, and limb-bone fragments of Elephas sp. have recently been recorded with a premolar of Hippotigris suessenbornensis and molar fragments of Hippopotamus and Mastodon. Many of the peculiar, phosphatised and worn fragments of Platax woodwardi are present—particularly in the basal part of the Upper Shell Bed. All the remains of the mammals mentioned, and of Platax, are relatively heavily mineralised and are most probably derived, but the palatal teeth of Raja clavata —which were also found—could well be indigenous. The frequent Tellina specimens with united valves which occur in the Lower Shell Bed suggest that conditions of deposition were probably less turbulent than in Upper Shell Bed times.

The preservation in this way of complete specimens of Tellina may be partly due to their tendency to adopt a burrowing habit in life. In the sand unit between the two shell beds complete Tellina specimens are frequent and are locally concentrated into two distinct bands, suggesting that conditions—at the time of deposition of this unit—were most tranquil. As a whole, the unit possibly represents an influx of sediment spreading over

STR ATI GRAPH Y AND FAUNA OF EASTON BAVENTS

167

the shallow-water shell banks which subsequently formed the Lower Shell Bed. Slight pauses during the deposition of the sand between the shell beds allowed Teilina spp. to colonise the sea bed—producing the regulär shell seams. It is thought that this sand unit was deposited at a somewhat greater depth than the shell beds and that the Upper Shell Bed represents a return to shallower and more turbulent conditions. Few of the members of the fauna present can survive exposure, though some, such as Mya, to-day ränge over both sandy and muddy environments.

The general impression is that the shell beds were deposited in a depth of water between four to fifteen fathoms.

The appended faunal list is compiled from the given sources and is the most complete published list for the Easton Bavents cliff exposures.

FAUNAL L I S T FOR T H E NORWICH CRAG OF EASTON BAVENTS Compiled from :— 1.—G. S. Memoir " Pliocene Deposits of Britain," 1890. Clement Reid* 2.—Q.J.G.S., Vol. 27. " Crag Beds of Norfolk and Suffolk."

Prestwich.

3.—Material from Easton Bavents in the Crowfoot and S. V. Wood Collections at Norwich Castle Museum.

4—Collecting in September, 1952, by G.P.L. and A.J.M. 5—Collecting in 1951-52 by Messrs. D. and P. Long.

1 Mammalia. Balaena sp. (vertebrae).

Cervus sp. (metacarpal and vertebra).

Elephas sp. (teeth, skull fragments and limb-bone fragments).

Hippotigris suessenbornensis (premolar).

Hippopotamus sp. (molar).

Megaceros verticornis.

Mastodon sp. (molar).

Microtine incisors.

Pisces.

Platax woodviardi (clavicles and vertebrae).

Raja clavata Linne.

Otoliths.

2

3

4

5

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* S i n c e the 1948 International Geological C o n g r e s s held in L o n d o n the R e d and N o r w i c h Crags are considered to b e Pleistocene.—H.E.P.S.

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STRATIGRAPHY AND FAUNA OF EASTON BAVENTS

1

2

3

4

5

ECHINODERMATA.

Echinoidea. Echinus sp. (spines).

ARTHROPODA.

Crustacea.

Balarius crenatus.

B. porcatus.

Cancer sp. (claw).

Homarus sp.

MOLLUSCA.

LamelliAbra ovata Phillipi. branchiata. Anomia ephippium Linne.

Astarte montagui (Dillwyn) (=A. compressa).

A. semisulcata (Leach) (==A. borealis).

A. sulcata (da Costa).

Cardium edule Linne.

Chlamys opercularis (Linne).

C. princeps (J. Sowerby).

C. tigerina (Müller).

Corbicula fluminalis (Müller).

Corbula gibba Olivi.

C. striata Walker and Boys.

Cyprina islandica (Linne).

Donax vittatus (da Costa).

Dosinia lupinus lincta (Montagu) (=Artemis lincta) Ensis siliqua (Linne).

Gafrarium tninimum (Montagu) (=Circe minima).

Glycimeris glycimeris (Linne).

Hiatella gallicana (Lamarck) (=Saxicava rugosa).

Modiolus modiolus (Linne).

Mya arenaria Linne.

M. truncata Linne.

Mytilus edulis Linne.

Nticula cobboldiae j f . Soiverby.

N. tenuis (Montagu).

Ostrea sp.

Phacoides borealis (Linne) (—Lucina borealis) Serripes groenlandicus (Bruguiere) (—Cardium groenlandicum).

Sphaerium corneum (Linne).

Spisula arcuata (J. Sowerby).

S. elliptica (Brown).

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*

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*

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STRATIGRAPHY AND FAUNA OF EASTON BAVENTS

169

1 2 3 45 S. ovalis (J. Sowerby). * * * * * S. subtruncata (da Costa). * * * Tellina fabula Gmelin. * * T. lata Gmelin. * * * * * T. obliqua J. Sowerby. * * * * * T. praetenuis Woodward. * * * * * Venus ovata (Pennant). * Yoldia oblongoides Wood (non myalis Couthouy). * * * * * Gastropoda. Acteon tornatilis (Linne). * * Amauropsis islandica (Gmelin) (=Natica helicoides). * * * Arianta arbustorum Linne. * Buccinum undatum Linne. * * B. undatum var. groenlandicum S. V. Wood. ? non Chemnitz. * Liomesus dalei (J. Sowerby) (= Buccinum dalei). * * Littorina littorea (Linne). * * * * * Lora reticulata (Brown) (=Bela trevelyana). * Lymnaea peregra (MĂźller). * Melampus pyramidalis (J. Sowerby). * * Nassarius propinquus (J. Sowerby). * * N. reticosus (J. Sowerby). * * * Neptunea antiqua (Linne). * * * * Nucella lapillus (Linne). * * * * * Polinices catena (da Costa). * P. catenoides (Wood). * * * Scala groenlandica (Chemnitz). * * * Turris turricida (Brocchi). * Turritella communis Risso. * * * * * T. incrassata (J. Sowerby) * * Viviparus medius (S. Woodzvard) (refers to Paludina lenta and Paludina vivipara Auct.) * * ACKNOWLEDGMENTS. The authors would like to thank Mr. R. A. Long of Lowestoft, and Mr. H. E. P. Spencer of Ipswich Museum, for permission to examine material collected from Easton Bavents. Thanks are also due to Mr. E. A. Ellis for permission to examine the Crowfoot, Norton and Searles Wood collections at Norwich Castle Museum and for other assistance, and to Mr. C. P. Castell of the British Museum (Nat. Hist.) for valuable assistance in revising the nomenclature in the list of Mollusca.

PLATE II.

DIAGRAMMAT1C SECTION OF THE CLIFF EXPOSURES FROM S O U T H E N D WARREN-SOUTH W O L D T O E A S T O N BROAD - SUFFOLK.

TOPSOIL, " P e 6 6 L Y S E R i E S " - c & n d f c <xc»«A <j»-<xvels.

CHILUfeSPO«.t) CLAV, NORWICHCRA.Q - 6 a n d s A n d « h e l l b e d s .

-reJfer t o

O . S H63360

SUt.137.

N

518787

5 7 f l

PLATE

FIG.

I.

1.

1-1G. 1 . — N o r w i c h (Jrag Sands w i t h shells and shell-beds o v e r l a i n C h i l l e s f o r d Clav—F.aston Bavents C L i f f s — G . R . 518787.

by

PLATE

FIG.

I.

2.

FIG. 2.—Channelled and current-bedded Pebblv Series—Easton Bavents Cliflfs—G.R. 516779.

170

STRATIGRAPHY

AND FAUNA OF EASTON

BAVENTS

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15 _Woodward, H. B., 1888. " Report of the Sub-Committee of the Geological Congress—Recent and Tertiary."