Geological Society. 319 



miles north-east from Edinburgh. The promontories which form the 

 two extremities of the bay of Elie, consist of amygdaloid and basalt, 

 the latter exhibiting sometimes a columnar structure. Between these 

 headlands the beach is low, and composed of alternating, thin beds of 

 sandstone and shale, with occasionally seams of coal and strata of 

 limestone, the whole belonging to a carboniferous system, and in- 

 clined at high angles in different directions, and without any regu- 

 larity. Basalt occurs in numerous places, extending in long reef's 

 far into the sea ; the beds of sandstone and shale dipping from them 

 on both sides : but at one point in the western part of the bay the 

 strata are said to dip under the basalt. 



About two miles to the eastward of Elie is a small promontory, 

 near the extremity of which is situated the bed of marine shells. The 

 extent of the deposit across the promontory does not exceed eighty 

 yards j but its range inland could not be ascertained. The bed rests 

 unconformably upon strata of sandstone and shale containing masses 

 of ironstone, and consists principally of coarse sand, with rounded 

 fragments of the sandstone and ironstone. The shells are sometimes 

 imbedded in clay, but are more frequently scattered irregularly through 

 the deposit, and belong, without exception, to existing species. The 

 point at which they were first noticed, is about five feet above high- 

 water mark, and the shells were very much broken. As the bed gra- 

 dually rose towards the north-east, they were more numerous, and 

 better preserved ; the greatest height at which they were noticed, by 

 the author, being twelve or fourteen feet above the level of high tide, 

 and on the east side of the promontory. The deposit passes upwards 

 into fine sand and comminuted shells. The strata, on the basset 

 edges of which the shelly bed rests, Mr. Hamilton conceives were 

 thrown into their highly inclined position by the agency of the neigh- 

 bouring trap, and before the accumulation of the gravel and sand ; 

 but that in consequence of the angle presented by the latter, and the 

 distribution of their component materials, a subsequent elevatory 

 movement has taken place, to which he ascribes the difference of level 

 between the deposit and the present shore. 



A paper was afterwards read, entitled "Observations on the Dilu- 

 vium of the vicinity of Finchley, Middlesex 5" by Edward Spencer, 

 Esq., F.G.S. 



The district occupied by this deposit extends from Muswell Hill to 

 Finchley Common, a distance of about three quarters of a mile : its 

 breadth is about 150 yards, and its average thickness is from 15 to 

 20 feet. The best point for examining the deposit is at the gravel- 

 pits in the lane leading from Muswell Hill to Colney Hatch. It pre- 

 sents, immediately beneath the vegetable soil, a bed about 14 feet 

 thick, consisting of marl and waterworn fragments of granite, por- 

 phyry, micaceous sandstone, mountain limestone, coal, lias, oolite, 

 and chalk, with many of the characteristic fossils of these formations. 

 The most abundant pebbles are lias and chalk j the latter being in so 

 great quantity as to give the whole accumulation a chalky character. 

 Flints are likewise sufficiently numerous to be extracted for repairing 

 the roads. 



