COKRESPONDENCE. 
53 
ing the lower Neocomian clay strata, " the ^Middle and Lower division " of 
Fitton. 
Here, however, there is an abrupt change. The finely stratified deposits 
which have hitherto prevailed are overlaid by an accumulation of coarse 
Band and 2Jehbles ; the stratum or strata composed of these materials varying 
in thickness from a few inches to six or ten feet, and contrasting strongly 
with the sands beneath. The " pebble-beds " are succeeded by various 
strata of coarse gritty sand, abounding in concretions of limestone* and 
chert ; in all of which small pebbles and thinla5'ers of clay are of frequent 
occurrence. These, in turn, are followed by a series of ferruginous sandy 
deposits of considerable thickness, which range upwards uninterruptedly 
to the Gault. 
It is to the occurrence of these " pebble-beds " and of the superincum- 
bent limestone, in the Greensand of Godalming and elsewhere,t that I 
would noYN direct attention, as being possibly connected with the present 
subject of inquiry. 
There is another subject, however, so closelj' connected with every ques- 
tion relating to the Greensand, that I find myself compelled to notice 
it before proceeding further. 
Mr. Jl. Godwin-Austen, in a valuable paper " On the possible Extension 
of the Coal-measures beneath the South-Eastern part of England, argues 
the existence, during the Oolitic, Wealden, and Neocomian period, of a 
ridge of old rocks (pahTOzoic) extending across o\ir south-eastern counties 
nearly in the line of tlie North Downs. This ridge the author traces 
eastward, in connection with a well-marked Continental axis, called by him 
the " Axis of Artois," and westward, into the district of Eath and Erome. 
For the capital reasoning upon which that author's supposition is founded, 
I must refer the reader to the original paper. Yet it cannot fail to strike 
the observer, that such a ridge, supposing it to have existed as a coast-line 
during a lengthened period, must have exercised considerable local influ- 
ence upon the surrounding deposits, whether of the Oolitic or Cretaceous 
formation ; so that the surrounding deposits ought, in themselves, to con- 
tain some direct proof of its existence. Such proof, if I mistake not, may 
really be found in the " pebble-beds " of the Lower Greensand. Of these, 
Mr. Austen says, " The shingle-beds of the Lower Greensand of Kent and 
Surrey contain a considerable number of extraneous fossils, such as the 
bones and teeth of Oolitic saurians. Ammonites Lamhcrti and Am. crena- 
ills of the Oxford clay in great abundance, together with Terehratula 
fimbria and RhynchonelLa oolitica ; " and instances these as having been 
derived from the wearing away of members of the Oolitic group, which, 
lie suggests, may have been originally brought up against the southern 
slope of this old ridge " by a process of successive overlap." 
In confirmation of this opinion I may here mention that, previously to 
becoming aware of Mr. Austen's researches, I had obtained from the 
"pebble-beds" of the Lower Greensand of Godalming a series of drifted 
fossils, ranging in age from the Oxford clay to the Lias inclusive ; and, 
from the evidence of these alone, I had come to the conclusion, that at the 
time of their deposition in the Greensand the rocks from whence they were 
derived must have existed within a short distance to the northward. § 
* Locally called " Bargate stone." 
t Along the North Downs. A pebble-bed also occurs in the cliff north of Shankliu 
chine, holding exactly the same position in the Greensand. 
X Quar. Jour. Geol. Soc. vol. xii. p. 50. 
§ My reason for looking northward for such land -surface arose partly from t^d fact of 
the pebble-beds becoming gradually thicker, and their component parts coarser, in thit 
direction. 
