Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/281

 without sand, apparently destitute of organic remains, and never exceeding two or three inches in thickness.

The fossils in the three red beds are for the most part similar, and suggest the inference that all three bands may be considered as forming a single division and composing one geological stratum. In the case where certain fossils have been seen only in the lowest part, their absence elsewhere may be accounted for on the ground that the upper bed (A) is less numerically abundant in organic re- mains than are those below, and that the middle bed (B) is so ex- ceedingly hard and compact as to diminish the chance of discovering fossils. Avicula gryphceoides and Spongia paradoxica would seem, however, to be special to the upper part of A, the highest of the three red beds. The dip of these beds in the cliff is about 2°, to the north ; sections inland taken at right angles give the same num- ber of degrees to the easlj^

Many visits to the Hunstanton Cliff, undertaken at intervals during the last ten years, have enabled me to gather together a very fair collection of the species peculiar to the red beds. The follow- ing list, taken from specimens in my cabinet, may therefore be re- garded as representing the general fauna of the " Red Chalk." From this list are purposely excluded doubtful species and mere varieties of form, those only being introduced which can be safely defined. As a matter of interest, the numerical frequency of the fossils and their position in the three divisions are recorded. The letters v. c, c, r., v. r., in the fourth column stand for very common, common, rare, and very rare, and imply the relative abundance of the various species. The mark * in one or more of the first three columns shows that the fossils to which it is affixed have been met with in such bed or beds.

Fossils from the Bed Chalk.

Highest Band, A.

Middle Band, B.

Lowest Band, C.

Frequency.

Spongia paradoxica, Webster

Scyphia tenuis, Roemer

Berenicea regularis, D' Orb

Proboscina dilatata, jD' Orb

Reptomulticava mamilla, Reuss ....

Stomatopora longiscuta, D' Orb

Micrabacia coronula, Goldf,

Cyclolites polymorpha, Goldf.

Podoseris mamilUformis, Duncan. .

elongata, Duncan

Bourgueticriaus rugosus, Ag

Torynocrinus canon, Seeley

Pentacrinus Fittoni, Aust

Cidaris gaultina, Forbes

-, n. s., spines, Wright (Cret. Echin., pl. xii. fig. 8) Pseudodiadema Brongniarti, Ag