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FIELD MEETING AT GUILDFORD AND THEGUILDFORD BYPASS.

Saturday, 21st June, 1945.

Report by the Directors: Miss Emily Dix, D.Sc., F.G.S., andMajor C. W. Wright, M.A., F.G.S.

[Reaived 10th September. 1945.)

THE first party of members travelled to Guildford by an earlytrain to examine the brick pit of the Sussex and. Dorking

United Brick Company near Guildford, where Reading Beds andLondon Clay are exposed. The Iiighly fossiliferous shell-bed inthe former yielded abundant specimens of Cyrena spp., Brotiainequinata Defrance and fragments of Ostrea bellovacina Lamarck,while several members found examples of the characteristic fishteeth (Odontaspis). Small crystals of selenite, which had formedon the weathered surface, were also examined.

Additional members arrived shortly after 2 o'clock, and thewhole party of 30 then walked through the Onslow housing estateto a small chalk-pit in the zone of Offaster pillula just south of theeastern end of "Curling Vale." This is the only permanentexposure of the zone in Surrey and has yielded a considerablesuite of fossils. The zone fossil and Actinocamax granulatus(B1ainviIle), which occur here , were unfortunately not found onthis occasion, but members quickly extracted specimens ofEchinocorys scutatus (Leske), chiefly Brydone's form depressula,Ostrea canaliculata Sowerby, O. vesicularis Lamarck and polyzoa.

Lack of time prevented examination of the now largely over­grown Wilderness pit in the Marsupites zone, but its site was pointedout.

Advantage was taken of the magnificent prospects from theHog's Back ridge to explain on the ground the geology of thedistrict, before the Bypass sections were examined in detail .

The first cutting at the crest of the Hog's Back furnishedcharacteristic fossils, including the zonal index, of the zone ofMicraster coranguinum. Several small specimens were found ofGibbithyris ellipsoidalis Salmi, which is not uncommon here, anda single example of Aequipecten pexatus Woods, a rarity at thishorizon.

The base of the Micraster cortestudinarium zone was nextexamined south of the crest of the ridge. Specimens of the zone­fossil and of M. praecursor Rowe were soon found. The zone ofHolaster planus, which is well exposed, yielded abundant fossils,including the zone-fossil, Micraster leskei Desmarest, M. corbovisForbes several species of Gibbithyris and a few molluscs of " ChalkRock" type, among them a fine Prioncyclus. This ammonite,found by Mrs. O. D. Suggate, is not one of the species of the

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genus recorded for this country and is probably new. Two dipfaults and one of the Hog's Back reversed strike faults were pointedout and the structure of the Hog's Back was discussed.

Passing through cuttings, now overgrown, in Gault, FolkestoneSands and Bargate Beds, the party reached Compton, wheremuch-needed tea was enjoyed at the" Coffee House." The returnjourney was by the Pilgrims' Way, along the outcrop of theFolkestone Sands, first through the woods and then along SandyLane into Guildford.

Acknowledgments are due to the manager of the Sussex andDorking United Brick Company's Brickworks and to Mr. W. P.Robinson, the Surrey County Engineer, for permission to examinethe sections.