PROF. T. M‘K. HUGHES ON SPONGIA PARADOXICA. 273 
19. On the so-called Sponeia PARADOXICA, 8. Woodward, from the 
Rep and Warr Cuatx of Hunstanton. By T. M°Kenny 
Hvueuuzs, M.A., Woodwardian Professor of Geology, Cambridge. 
(Read February 20, 1884.) 
Tue sea-cliff of Hunstanton in Norfolk offers one of the most 
interesting sections along our eastern coast. We there have an 
opportunity of examining in detail all the beds from well down in 
the Lower Greensand fairly up into the Chalk, and we see that, 
where we should have expected to find the Gault and Cambridge 
Greensand, there is instead a conspicuous band of red rock about 
4 feet in average thickness, which, when examined closely, seems 
to pass up into the Chalk above, part of the lowest bed of which is 
mottled with stains and nests of red earthy oxide of iron, and to 
pass down through more and more sandy layers into the Lower 
Greensand underneath, as if it was either largely derived from the 
Lower Greensand, or the conditions of deposit of the Lower 
Greensand were still gomg on while the earlier part of the Red 
Rock was being formed. When we stand off at a little distance, 
however, the line of demarcation appears more sharply defined by 
the results of weathering. Paleontologically, too, it is a section of 
great interest. The Red Rock and the lower part of the Chalk are 
full of organisms of various kinds, of which lists have been given 
by Taylor *, Samuel Woodward, Rose £, Wiltshire §, Seeley ||, and 
others; and in these lists we find repeatedly the description or 
mention of a fossil which, from the time of Woodward on, was 
referred to under the name of Spongia or Siphonia paradowica. 
The bed at the base of the White Chalk is sometimes spoken of as 
the Sponge-bed, from the prevalence of these bodies, which have 
been supposed to be sponges. 
Taylor gives a good section and description of the beds seen (Phil. 
Mag. vol. lxi (1823), p. 81.) in the Hunstanton Cliff, in which he 
says, p. 82:—‘‘ No. 4. 14 foot. A stratum of white chalk, more 
loose than the last, containing no fossil shells; yet is distinguished 
by a remarkable species of ramifying zoophyte, resembling the roots 
of trees; about an inch thick, branching and interweaving in every 
direction. Some of the fragments are not unlike the horns of a 
stag.” And again, “ No. 6. 2 feet. Red chalk, of a rough disjointed 
structure, similar, except in colour, to No. 4, and, like it, though in 
* “ Hunstanton Cliff,’ Phil. Mag. vol. 1xi. 
t Geology of Norfolk, 1833. 
{ ‘Sketch of the Geology of West Norfolk,” Lond. & Edinb. Phil. Mag. and 
Journ. vols. vii. & viii. 1835-36. { 
§ “On the Red Chalk of England,” Geol. Assoc. Ap. 1859. ‘“ On the Red Chalk 
of Hunstanton,” Quart. Journ. Geol. Soc. May 1869. . 
|| « On the Red Limestone of Hunstanton,” Ann. & Mag. Nat. Hist. April 1861. 
“On the Hunstanton Red Rock,” Quart. Journ. Geol. Soc. vol. xx. p. 327 (1864). 
Q. J. G. S. No. 158. T 
