February 19th, 1895.


Rev. H. E. MADDOCK, M.A.,F.G.S.


Mr. Maddock said the sections of the chalk in the South of England were much more easy to work out than they are in most parts of the North of England. He had worked continuously for three years at the lower beds of the Upper Cretaceous series which were then, magnificently displayed between Eastbourne and Beachy Head. The sea wall, that great enemy to geological research, which now entirely conceals from sight the base of the cliff between Eastbourne and Holywell was then in course of construction and many opportunities for collecting fossils occurred as the work proceeded.


The lecturer then described, in ascending order, the position and character of the successive beds between the Wish-point near Eastbourne and Beach), Head which rises to the height of 600 feet, three miles to the West.




Eight feet of the upper part of this bed, almost entirely unfossiliferous, forms the base of the cliff at the Eastern corner of the Wish- point.




Forms the upper and remaining part of the cliff at the Wish-point. In the lower twenty-six feet of this bed fossils are rare, but immediately above, occurs a hard bed (4 feet) often called the Chloritic Marl, (corresponding to the well-known Coprolite Bed at Cambridge) crowded with fossils, mostly in the form of phosphatic casts.




Is thirty feet thick and forms the base of the cliff for a quarter of a mile. At its base occurs the Sponge bed one foot in thickness, full of branching sponges formerly called Brachiolites, now called Plocoscyphia moeandrina. This bed may be regarded as a transition bed between the Chloritic Marl and the Chalk Marl. The Chalk Marl consists of hard bands of bluish white argillaceous chalk, about one foot thick in which the chalk seems to be almost conchoidal in structure. The Chalk Marl is fairly fossiliferous, and may be put down to the Zone of Ammonites Varians and Rhotomagensis -- Rhynchonellae are very abundant. The chief echinoderm is Holaster levis var. Trecensis.




Six feet thick and called locally the Scaphites bed. May be regarded as a passage bed between the Chalk Marl and the Grey Chalk. It is more thickly bedded and softer than the chalk underlying it and abounds in fossils, chiefly in the form of casts. From this stratum, not far from the Wish Tower, the lecturer obtained a remarkable series of Turrilites, numerous Scaphites, Hamites and Baculites, besides many gastropods, which are seldom found in the chalk except at this horizon, and in the Chalk rock. The prevailing Pecten is Pecten orbicularis -- which Mr. Hill also records as the characteristic fossil of the Grey Bed at Speeton.



Eighty feet thick, consists of thick beds of hard Grey Chalk separated by marly bands of a few inches in thickness. It forms the base of the cliff till nearly the middle of Holywell Bay, and as a rule is poor in fossils. Holaster subglobosus and Terebratula semiglobosa, however are plentiful.




Ten feet in thickness, forms the base of the Synclinal at Holywell Bay, where it occurs in the form of two bands of argillaceous chalk, very hard and compact, separated by a whiter chalk band of three or four feet. The one fossil, fragments of which are plentiful, is Belemnitella plena, which gives its name to the zone.


The bed may be regarded as a transition bed between the Middle and Grey Chalk, belonging rather to the lower beds than the upper.




Thirty feet thick. This bed begins the Middle Chalk and consists of thick courses of extremely hard crystalline chalk, almost entirely made up of fragments of shells chiefly Inoceramus Mytiloides with numerous specimens of Terebratulina gracilis and of a small Echinoderm, Discoidea minima. Between these thick beds are bands of nodular chalk, described as brecciated and concretionary, Homomomy, formed apparently of rolled fragments of locally called the underlying beds in a matrix of exceedingly hard siliceous chalk. This proves clearly that there is here a definite break in the Cretaceous series, and it is about this horizon that M. Barrois separates between the Cenomanian and the Turonian series.


Above the Grit beds before the first flint band is reached, comes one hundred and twenty feet more of massive chalk in thick beds, the characteristic fossils of which are Echinoconus subrotundus, Rhynconella cuvieri and Spondylus spinosus. About twenty feet below the flint band the bed changes in character both lithologically and paleontologically. The chalk becomes whiter and softer and is filled with Ventriculites in the form of casts, Ventric. impressus being especially plentiful while the characteristic Inoceramus is Ioceramus brongniarti and Micraster cor. bovis is occasionally found. It is interesting to notice the great difference in the thickness of the chalk between the blue band and the lowest line of flint in the different parts of England.


At Eastbourne the thickness is about 140 or 150 feet,

At Dover the thickness is about 120 feet,

At Hitchin the thickness is about 45 feet,

At Lincolnshire the thickness is about 15 feet,

At Speeton the thickness is about 8 feet,


Mr. Wm. Hill in the Quarterly Journal of the Geological Society of London Vol. XLIV., describes the lower chalk of Lincolnshire and Yorkshire and the appended diagram of the Speeton section is taken from Mr. Hill's paper.


chalk at Speeton and Eastbourne 


In conclusion Mr. Maddock said that the notes from which this lecture had been compiled were made before M. Barrois's visit to Eastbourne, the results of which are contained in his very valuable work on the English Upper Cretaceous beds. In the main the results at which the lecturer had arrived were confirmed by M Barrois though the presence of a portion of the sea wall at the time of M. Barrois's visit had prevented him from noting the occurrence of Gault as forming part of the Cliff at the Wish Point, and also the occurrence of the Cast- Bed as a division between the Chalk Marl and the Grey Chalk.



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