PROCEEDINGS 



OF 



THE GEOLOGICAL SOCIETY OF LONDON. 



1831. No. 21. 



March 2nd.— Robert McCallan, Esq. of Hampton Wick, Mid- 

 dlesex ; the Very Reverend the Dean of Carlisle ; and William 

 Hawes, Esq. of Russell Square, — were elected Fellows of this Society. 



A paper was first read " On the rippled markings of many of the 

 forest marble beds north of Bath, and thejbot-trach of certain ani- 

 mals occurring in great abundance on their surfaces." By George 

 Poulett Scrope, Esq., F.G.S., F.R.S. 



The wavy and wrinkled figuring of these and other sedimentary 

 strata, the author considers to be identical in all its various acci- 

 dents, as well as in its origin, with the markings of the sea-sands 

 exposed at low tide on many of our shallow shores. He attributes 

 it to the vibratory movement of the lower stratum of water, when 

 agitated by winds or currents, by which sediment, either in the act 

 of precipitation or stirred up from the bottom, is led to arrange 

 itself in ridges corresponding to the intervals between the contigu- 

 ous arcs of oscillation. 



Since it cannot be supposed that such movements reach to any 

 very considerable depths, these ripple-marks make it probable that 

 the beds in which they occur were formed on a shallow shore ; and 

 this idea is further confirmed, and their analogy with the littoral 

 deposits of our modern coasts brought still closer, by their compo- 

 sition of rolled fragments of shells, of corals, spines of echinus, and 

 Crustacea, by the imbedded remains of fuci, and above all by the 

 frequent intersection of their surfaces by the sharp well-defined and 

 fresh-looking tracks of some small animal, impressed upon the sand, 

 apparently when left dry by the ebbing of the tide. 



Here then, says the author, we have brought together in the 

 compass of a small slab, several interesting memoranda of the day, 

 however distant, when the waves of the ocean were beating against 

 a line of coast now in the centre of our island ; and a new class of 

 facts to assist in better deciding the question as to the date of 

 emergence of the different successive formations from the bosom of 

 the deep. 



Mr. Scrope does not hazard a conjecture respecting the genus 

 or even the class to which the animal may have belonged ; leaving 

 it to zoologists to determine whether it be marine, terrestrial, or 

 amphibious. He, however, earnestly recommends geologists in 

 every quarter of the globe to examine minutely the surface of sand- 

 stones, and other sedimentary strata, particularly where ripple- 



