532 EX CURSION TO SALISBURY AND STONEHENGE.

1881. H U:DLESTON, W. H.-" Excursion to Salisbury, Stonehe nge, and Vale of Wardour." 'Proc. Geol. Assoc.,' Vol. vii (No.2), p p, 134-142. 1882. STEVENS, E. T.-" Jottings on Some of the Objects of Interest in the Stonehenge Excursion." 8vo. Salisbury (Brown & Co.) and . 38.6d. 1884. CUN NINGTON , W.-" Guide to the St ones of Stonehenge " (a plan, distinguishin g the various stones,wit h brief description). Bvo. Devises (H. F. Bull, 4, St. J ohn Street). 6d. 1884. CUNNINGTO N, W.- '· Stonehenge Notes : The Fragments." 'Wilt­ shire Mag.," Vol. xxi, p, 141 (Plan). " Notes on the Fragments," by T. DAVIES.

EXCURSION TO AND .

SATURDAY, MAY 1ST, 1886. (In conjunction with the Sutton Scientific Society.),

(Rep0l"t by H. HUTCIIINS FRENCH, F.G.S.) The party assembled about three o'clock at the rooms of the Sutton Scientific Society, where th ey were joined by some of its members. They th en proceeded westwards along th e ancient way from Croydon to Guildford, which is now here a mere footpath. This road is interesting geologically as runnin g almost exactly along th e outcrop of the Thanet Sands ; it is bordered throughout its length by a line of ancient villages, whose sites were determined by the water-supply afforded by the sands. At Boney Hole, in Fi elds, th e Dire ctor pointed out the derivation of th e term "Bourne" Hole, it being one of the points at which th e intermittent stream known as the Bourne issues. The flow of the Bourne is determined entirely by an excessive amount of winter rainfall, and is in no sense periodic as popularly supposed." Mr. Skertchly mentioned that experiments which he is now engaged upon with reference to evaporation from the Chalk supported the views of th e Director, that only th e winter rainfall affects the underground water-level. Close by, a small exposure of the Thanet Sands was seen, capped by the clayey base of the Reading Series. At Cheam the party was met by the Rector, and visited the Lumley Chapel, where he and Mr. E. Locke, A.R.I.B.A. (of * ' On Bournes,' by H. H. French, F.G.S., 'Proc. Sutton Scientific Society, 1883.' EXCURSION TO EWEI,I, AND EPSOM. 533

Sutton), described the interesting plaster-work and monuments, and the brasses, including some of the oldest palimpsests in . Proceeding through , across small outliers of the Thanet Sands, Nonsuch Kiln, at Ewell, was reached. Here a fine section of the whole series of the Reading beds is exhibited, together with the top of the Thanet Sands. The succession is as follows :- ft. in. 1. Soil 4 0 2. White sand 5 0 8. Mottled clays ... 13 0 4. Line of small black pebbles .., o 2 5. Glauconitic sands, with thin bands of red clay occurring at intervals ..• 5 o 6. Brownish laminated clay (with shark's-teeth) 2 o 7., Blue" dicey" clay 5 o 8. Thanet Sands (white), seen to 5 o 89 2

The Director here explained that this and the other pits to be visited had been studied by some of the members of the Geological Sub-Committee of the Sutton Scientific Society, under the guid­ ance of Mr. S. B. J. Skertchly, F.G.S., and the following points seem to be new :- Ist, Whereas the Reading Bed in this district has always been considered unfossiliferous, Bed 6 contains numerous shark's-teeth (Lamna), all young and of a white-porcellanous texture, the ordinary dark stony teeth being quite absent. The youth of the specimens seems to indicate quite shallow water. Bed 5, just beneath the line of pebbles, contaius a seam crowded with what appear to be annelid borings. 2nd. The only marked physical junction occurs at the base of the mottled clays, the passage between the Thanet Sands and the overlying "dicey" clay (Beds 8 and 7) being absolutely imper­ ceptible. Mr. Starkie Gardner here remarked on the peculiar nature of the flora of the Reading Series, which is quite temperate in aspect, being characterized by such forms as the Plane. He would divide the Woolwich from the Reading Series on palreontological and physical grounds, and with regard to the present section would VOL. IX. .Ko, 8. 38 534 EX CURSION TO EWELL AND EPSOM. include all the beds beneath the mottled clays in the Thanet Series. The party th en visited a series of pits in the Reading Series, of which the most important were that of Mr. Chuter-in which a mass of " W ess " cuts righ t through the mottled clays i-and LintonLane pit adjoining, where the mottled clays are particularly brilliantly coloured. It was mentioned th at oysters occur in th e green sand close by th e last pit (apparently O. tenera), and at Epsom, in the same bed, O. bellovacina is plentiful and of large dimensions. Professor Rupert J ones gave two short addresses, one upon the surface gravel, the other upon the general relation s of the Lower Tertiaries. REFERENCES. MAPS. Ordnance Survey, New Series, Sheet 270. Geological Survey, Sheet 8. 1872. WHITAKER, W.-" Geology of the ." 'Mem. Geol. Survey,' pp. 22, 60, 108, 282. 1883. FRENCH, H. H.-" On Bournes'" Pro. Sutton Scientifio Soc.'

EXCURSION TO WELWYN.

SATURDAY, MAY 15TH, 1886. (In conjunction with th e Natural History Society.)

Director: JOHN HOPKINSON, F.L.S., F.G.S.

(R eport by THE DIRECTOR.) Outli ers of the Lower Tertiaries, consisting of the Woolwich and Reading Beds and the London Clay, arc scattered over the Chalk beyond th e north-west margin of the London Tertiary Basin, chiefly in a south-west and north-east direction, a few miles from, and roughly parallel with, the edge of this basin. A few, however, are found at a gr eater distance, thus attesting the former exten­ sion of the Tertiaries over a very large area of the Chalk, from which they have been removed by denudation. Of the outliers which follow the general line, two are in the neighbourhood of W elwyn, one (the Ayot outlier) being to the south-west, and the other (the Datchworth outlier) to the east of this town. The former of these it was the chief object of the present Excursion to visit and examine.