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up by grand but gentle curves, in orderly arrangement, around along elliptio dome, reaching from Alton on the west to Hastings, andbeyond the Straits to France, and worn down, by natural agencies.of long continuance, from a high broad ridge to the present com­paratively low series of lesser ridges, and drained by rivers, follow­ing the radiating cracks of the raised ellipse, which have still kepttheir outward course through sandrock and chalk downs,deepeningthe widened rifts until the Pluvial period was over-passed, and nowmeander slowly among the gravel-beds and alluvial flats, till theyreach the Thames on one side and the Channel on the other. Ontheir way to Guildford the geologists visited, near Titlings, a pit ofchalk-marl (used for plaster-lime), where the beds, upturned at anangle of 80°, afford a key to the general configuration of the country,as they show by local intensity the bending force to which all thestrata have submitted. After some refreshment at Guildford, Mr.Meyer led the party to a quarry of the Lower Greensand west ofGUildford, where the upper member of this interesting formati~n iswell seen, with its oblique bedding and numerous regular faultmgs,and where its fragmentary shells, corals, and other organisms can belargely collected. A hasty visit to St. Catherine's Chapel, on theknoll of Lower Greensand, overlooking the railway, the valley, andShalford Park, ended the expedition, which, favoured throughoutwith glorious sunshine, now broke up, amidst congratulations on asuccessful day and a happy meeting of mutual pleasure and instruc­tion, with a hearty desire to meet again in that beautiful countyunder the guidance of the same good leaders.

THE EXCURSION TO CATERHAM JUNCTION & CROYDON.

By CALEB EVANS, F.G.S.

ON Saturday, 19th June, 1869, a party of the members of theAssociation and their friends, proceeded by train to CaterhamJunction, arriving there about a quarter past three. The party atonce entered the fine Chalk pit adjacent to the station.

The attention of the visitors was first directed to the faults in theChalk, several of which were very clearly exposed. One inparticular was very conspicuous, descending in an oblique directionfrom the top nearly to the bottom of the pit, and causing a downthrow of about 15 inches to the east. This down-throw was wellseen at the points were the bands and tabular deposits of flint wereparted by it. In another fault, the space between the sides of thefault, was filled by an ochreous marly deposit. High up in the faceof the cliff, one of the sides of this fault was exposed, presentingthat remarkable grooved and rubbed appearance, known as slicken­sides.

Professor Morris then directed attention to some remarkable

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bands of nearly. continuous tabular flints, and pointed out that thesebands might possibly be traced for considerable distances, thusassisting in the determination of exact horizons in the chalk. Healso suggested that several bands of chalk which appeared stainedof a yellow colour, would probably be, found to abound withsponges.

Several fine examples of the remarkable hollows in the surface ofthe chalk known as sand-pipes, resulting from the dissolution of thecalcareous matter by the percolation of water were well seen, andthe remains of a very fine one was observed, which had been wellexposed during the summer of last year, and seen at that time todescend perpendicularly from the top to nearly the bottom of the pit.

The fossils obtained from the men, consisted chiefly of the teethof fishes.

Fragments of shells and foraminifera were seen on the surface offlints, and many flints were found to contain fine spicula of sponges,and portions of ventriculites. The prevailing dip of the beds in thispit, is at at a slight angle to the North.

On leaving the pit, the party proceeded along the road up thevalley towards Caterham. Immediately opposite the lane leading toKenling Station, a halt was made for the purpose of examining asmall pit in the face of the down beside the road.

This pit showed beds of chalk at a somewhat greater inclinationthan the beds in the Caterham Junction pit, the chalk. towards thesides below the slope of the hill, also presented a curved arrange­ment, and was much disintegrated, the result apparently of denuda­tion, and the action of the weather.

The absence here of regular bands of flints was noted, a fewisolated flints however were seen, and several of these contained fineexamples of sponges. Specimens of sponges were also obtained inthe chalk itself, as well as the little Terebratulina gracilis, whichappears to be most abundant about this horizon in the chalk. Thebeds here exposed were probably the lowest seen during theexcursion, and were considered to belong to the upper portion of themiddle chalk.

Once more proceeding along the road, the presence by the side ofthe road of blocks of conglomerate or pudding stone, composed ofrounded flint pebbles cemented into a hardTock, caused the attentionof the party to be directed to the vast amount of chalk and flintswhich had been removed by denudation. Professor Morris pointedout that the thick deposits of flints in the Eocene pebblebeds ofWoolwich, Bromley, and many other localities, and the flint gravelsso abundant in the river valleys, denoted clearly the great thicknessof chalk with flints (amounting possibly to as much as one thousandfeet), which had been completely removed.

From the well-known roadside Inn (the Rose and Crown), theparty advanced up the hill to the unfinished cutting at the Southernend of the tunnel, partly formed under Riddlesdown, for the Surreyand Sussex Railway. The strata here consisted of chalk, with con-

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spicuous bands of flints, and it was noted that by far the mostabundant fossils of these beds was Ananchytes ovata, Spondylu3spinosus being also very common. A remarkable example ofslickensides was observed immediately over the entrance of thetunnel, the peculiarity of which was that the grooves and strire werein a horizontal and not vertical direction, thus denoting not a fault,but a lateral shifting of the beds from south west to north east.

The party then proceeded to the top of Riddlesdown, the highestground in the district, and, having mounted one of the spoil heapsof chalk around one of the disused shafts of the tunnel, severalcuttings for the line of railway were pointed out to the southward.It was stated that the works of the line extended three or fourmiles beyond the points then in view, and that a long tunnel hadbeen commenced through the highest part of the chalk downs, to thesouth of which the line emerged on the valley of the Firestone andthe Gault. I then pointed out that (judging from the imperfectexaminations I have as yet been able to make of these railwaysections) the lowest beds above the Firestone and Gault appeared toconsist of Gray-chalk and chalk-marl in which Ammonites wereabundant, that these beds were succeeded by a band of hard chalk,with few if any fossils, and then by beds of white chalk in the lowerpart, without flints, and in the upper part with a few isolated flints,in which beds specimens of Inoceramus were very numerous, whileEchinoderms appeared to be rare, these beds extended nearly to theneighbourhood of the Rose and Crown, to the north of which thechalk with flints appeared characterised in the lower portion by theabundance of Ananchytes ovata, and in a higher portion by anequal abundance of Micraster coranguinum. In ascending the hillfrom the Rose and Crown, Professor Morris pointed out the in­teresting fact, that the jointed structure of the beds well seen in thelarge pit opposite the Rose and Crown produced masses of chalk of asomewhat rhombohedral shape, thus approaching to the crystallineform often assumed by carbonate of lime.

While assembled on the mound at the top of the hill, the Pre­sident directed attention to the physical features of the landscape,which in every direction showed evidence of considerable aqueouserosion, the slope of the small side valleys being in every instancetowards the larger Caterham valley, and wholly unconnected withthe strike or inclination of the strata, while the Caterham valleyitself sloped towards the main transverse valley extending fromMerstham to Croydon, through which the streams must formerlyhave flowed, until they finally reached the large valley of theThames.

The open condition in which the shaft of the tunnel had been left,enabled the party, before leaving this spoil heap, to observe aninteresting section of the superficial deposit, consisting of a bedtwo or three feet thick of reddish clay, with numerous chalk flintsresting on an extremely irregular and eroded surface of the chalk.This bed of "clay with flints" affords additional evidence of the

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great amount of denudation which the chalk has undergone. It isof very frequent occurrence in chalk districts, and is consideredto be derived from the argillaceous and silicious matter contained inthick beds of chalk left in situ after the whole of the carbonateof lime had been dissolved away.

Yet further evidence of the same fact was seen on the side of aridge to the north of Riddlesdown. No cutting had been com­menced on the south side of this ridge, but the turf had beenremoved, and the surface was found covered with angular andbroken flints of a white colour. The shattering of the flints, andthe discoloration were attributed to the action of the weather.Prof. Morris stated that most flints were more or less traversed byminute cracks, and the action of frost on the water contained inthese cracks results in the shattering of the flints.

On the north side of the ridge where these flints were seen, was achalk cutting showing a fine section of the chalk with flints. Aband of tabular flint was very conspicuous near the top of thesection, and it was suggested that this tabular band was possiblyan extension of one of those seen in the pit at Caterham Junction.

In the cutting to the north of this, and adjacent to the lanedescending from the high grounds to Purley House, the band ofchalk abounding with Micraster coranguinum, as before mentioned,was well seen, and several characteristic fossils were obtained bythe members.

This was the last cutting visited by the excursionists, who thenproceeded by the Sanderstead and Purley roads to Croydon, whereconvenient trains were obtained, enabling the members to reachLondon about 9 o'clock.

Sufficient was seen during the brief ~ interval devoted to thisexcursion, to show that many interesting facts may be observed, anda few hours very pleasantly spent in excursions to places easilyaccessible, and within short distances of the Metropolis.

THE EXCURSION TO HUNSTANTON.

(Abstracted from the' Geologieal Magazinf3' and' Mining Journal.')

The members of the Geologists' Association, accompanied by Prof.J. Morris, F.G.S., visited Hunstanton. Norfolk, on August 2nd, forthe purpose of examining the interesting geological features of thislocality.

Hunstanton Cliff, or St. Edmund's Hill, although of moderate ele­vation and extent, forms, from the comparative flatness of the adjacentcountry, a somewhat conspicuous object, and from the three distinctlymarked coloured strata (white, red, and brown) of which it is composedhas, when viewed from the north-eastern end, a very picturesqueappearance. At the highest part of the cliff about 60 or 70 feet