REPORT OF EXCURSION TO COULSDON, CHALDON ANDMERSTHAM.

(WEALD RESEARCH COMMITTEE EXCURSION.)

SATURDAY, JUNE IITH, 1927.

By A. G. DAVIS, Director.

[Report received October 31st, 1927.]

A SMALL party on arrival at Coulsdon North Station proceededimmediately along the station footpath which leads to theBrighton road, to examine the flow of the Merstham-CoulsdonBourne. The Director gave an account of the Bourne frominformation kindly provided for the occasion by Miss M. M.Herbert (1).

On reaching Messrs. Hall & Co.'s quarry in Marl Pit Lane,previously visited by the Association in 1923 (2, p. 224), an.exposure in the" Top Rock" horizon was pointed out whichhad not been detected by the Director in his earlier survey (3,p. 217). On this and earlier occasions the following fossils fromthis exposure were obtained by breaking up micrasters:­Aporrhais sp., Corbula sp., Emarginula d. unicostata (Seeley MS.),Gardner, Nucula sp., Parasmilia sp., Scaphites sp., and Serpula:sp.

In the short time allowed for collecting the party weresuccessful in finding characteristic fossils of the zone of Micrastercor-testudinarium. A good example of Pholidocladia ramosa,Hinde, was found on the flint heaps.

Walking over Farthing Down and by lanes to Chaldon theparty reached the top of the Chalk escarpment at Hill Top,where the hopes of a good view were disappointed by the.approach of a rainstorm.

A rounded boulder of Blackheath conglomerate, forming agate stop at Hill Top House was noticed. Many similar blocksare to be seen a few yards eastward in the chalk pits at WilleyFarm (No. 166, G. W. Young), where they occur in the driftwhich fills some large pipes. From Hill Top a steep lane,Pilgrim's Lane, descends the escarpment, showing roadsidesections in all the zones from Terebratulinalata to Schlcenbachiavarians. Some of the sections are mere scratchings laid bareafter heavy rains, but sufficient for the purposes of zoning andmapping.

The Varians.zone outcrops near the 500 ft. contour, and whenthe road was widened in 1923 a good section was exposed in thelower beds, and is still visible.

The following species were found in the cutting 300 yardsnorth of Rockshaw Road :-Schlcenbach£a varians (Sow.),

EXCURSION TO COULSDON, CHALDON AND MERSTHAM. 197

Plicatula inflata Sow., Rhvnchonella mantelliana Sow., andOnchotrochus serpentinus Dune.

At Spring Bottom, half-mile eastward and south of QuarryHangers, the lower beds of the Varians-zone are to be seen inhedge banks, where the following were found i-s-Schlcenbacbiavarians (Sow), Turrilites sp., Inoceramus crippsi Mant., Terebratu­lina striata Wahl., Rhvnchonella martini Mant., R. mantellianaSow., R. grasiana d'Orb., Onchotrochus serpentinus Dune., andPseudodiadema sp.

After tea at the Jolliffe Arms the road-cutting in the BrightonRoad at Merstham (2, p. 221) was examined. Although thegreater part of the section is now sloped and obscured by rain­wash, good exposures of the zones of Holaster subglobosus andRhynchonella cuvieri are still open. A good junction sectionshowing the Actinocamax plenus marl is exposed oppositeRailway Cottages near the Jolliffe Arms Inn.

With the kind permission of Mr. J. S. Peters the party visitedthe large quarry at the Greystone Lime Works. These arevery old workings, and are referred to by T. Webster (4), whogave a description as seen by him in 1821. They are againmentioned in the following year by Conybeare (5) and they nowform the talused and abandoned part to the south and east ofthe present quarry. In 1924 the Director cleared the talus atthe foot of this part of the quarry, and, in yellowish marly chalk,obtained many fossils indicating the zone of Schloenbachiavarians, namely Sch, coupei (Brong.), Sch. uarians (Sow.), Turri­lites costaius Lamk., T. tuberculatus Bose, Scaphites siriatus Mant.,Inoceramus crip-psi Mant., Ostrea uesicularis Lamk., Plicatulainflata (Sow.), Cardita sp., Terebraiulina striata Wahl., Terebratulabiplicata Sow., Kingena lima d'Orb., Serpula umbonata (Sow.),, Terebella ' sp. and, among others, an undetermined gasteropod.At the foot of the north-west face of the qUqrry there wasexposed in 1924 some massive hard grey chalk belonging to theupper part of the zone and yielding Acanihoceras cenomanensis(d'Arch.), Metacanthoplites rotomagensis (Brong.), andInoceramus crippsi Mant.

The present section, which occupied the whole of the northernface, does not differ from that described by Jukes Browne (6, p. 53)and shows 50 feet of the zone of Holaster subglobosus, the Actino­camax plenus marl, and above it about 30 feet of the zone ofRhynchonella cuvieri.

The following details of the zones are worthy of note :­Zone of Rhychonella Cuvieri.

Not infrequently flint nodules occur in this zone and areusually spongiform and rounded or oval in shape. The Directorhas seen only one specimen in situ, and about 15 feet above theActinocamax plenus marl. That the presence of flints in thispart of the chalk is unusual is borne out by the fact that examples

198 EXCURSION TO NEWHAVEN AND BRIGHTON.

are included in the quarryman's cachet laid aside for collectors .A similar instance of flints occurr ing in this zone has been recordedby G. E. Dibley in th e Medway area (7). Th ese two instancesconstit ute the lowest horizon of flints found in the Chalk ofKent and Surrey.

The following species occur in the nodular cha lk of this zonehere :-

Exogyra conica (Sow.), I noceram us labiaius Schlot ., T urnus ?am phis bcena [Goldf.} , Rhynchonella cutne ri d'Orb ., T erebratu linalata Eth., attached to a flint ; Asteroid marginals, Cardiasterpygm a:us Forb es, Discoidea dixoni Forb es, E chin oconus castane aBrong, E. subrotundus Mant. , Serpula amta Sow., and Siphouiaka:nigi Mant., in a flint .Z 0 n e of H 0 l a s t e r Sub g lob 0 sus.

The following were found in this zone on this excursion :­Holaster irecensis Leym , Cidaris bowerbanki Forbes, rad ioles only;Plicatula barroisi Peron , P . in fiata (Sow.), Lima globosa Sow. , andT erebratula biplicata Sow.

R E F ERE NCES.1. 1\1. M. H ERBERT. T he Merstharn-Coulsdon Bo urne. P roc. Croydon

N at. H is. and Sc . S oc. x. (192 7) . pp. 43-45 .2. A . G. D AVIS. E xcursion t o Merstha rn and Cou lsdo n, P roc. Geol,

A ssoc.. xxxvii. (1926) .3. A . G. D AVIS. Notes on some Chalk Secti on s i n N .E . Surrey. P roc,

Geol, A ssoc., xxxvii . (1926) .4. T . WEBSTER. T rans. Geol, Soc., v . (182 1), pp . 353-355. pl. 38, fig . 5 .5. CONYBEARE and PHILLIPS. Outline s of Geology . 1822. p . IS0.6 . A . J. J UKES B ROWNE. Cre taceo us R ocks of B ritain , II. (1903) .7. G . E . DI BLEY. Addit ion a l Notes on the Chal k of the Medway Vall ey.

P roc, Geol, A ssoc. (1918) , p. 74.

EXCURSION TO NEWHAVEN AND BRIGHTON.

SATURDA Y, 3 RD S EPTHlB ER , 1 9 27 .

REPORT BY C HRISTOPHE R T. A. G ASTE R, F .G.S . ,

Director o] the E xcursion.

[Rte eived December 4th. 1927.]

[AccJpted j ar pu blication December 16th, 1927.]

THE party, numbering twelve, assembled at Newhaven railwaystation and proceeded via the Harbour to Meeching Quarr y ,where through th e kindn ess of Messrs. H. Colgate an d Gray, anopportunity was afforded of examining the cha lk which is thereexposed. The lower part of the Quarry exhibits beds in theMarsupites-zone, and th e party were able to collect severalplates of Ma rsupites , togeth er with Rhynchonella plicatitis , Sow.and E chin ocorys scuta/us, Leske. The junction of the AI arsu pites-