578 



worn, are the most numerous, often forming considerable beds in « 

 loose or indurated calcareous sand. The dip of the strata is consi- 

 derable and to the south-east. The deposit may be traced some 

 way into the interior, and to elevations of 200 or 300 feet above the 

 sea, where there are quarries worked in ancient times; and on the 

 east to Nettuno, about a mile and a half from Antium, at which point 

 the upper beds rise to the surface. Passing thence to the west, and 

 beyond Antium, lower beds successively crop out for about a mile, 

 when the lowest, a sandy clay, appears, and continues for some di- 

 stance, nearly horizontal. It is overlaid in part by a bed of sand, 

 containing a layer of gravel in the lower part, and the two strata form 

 together a clifi 30 or 40 feet high. In the clay the fossils are not so 

 abundant, but are apparently of the same species as in the upper beds. 



About two miles from Antium, a thin bed of tertiary sandstone, con- 

 taining numerous abundance of the same fossils, begins to make its 

 appearance resting on the clay, and it gradually increases in thick- 

 ness to about 20 feet ; but then gradually thins out again to the west, 

 extending altogether between a quarter and half a mile. Below it, 

 20 feet of clay are exposed, and above it, a ferruginous sand, about 

 1.5 feet thick, through the lower 6 feet of which, some fine siliceous 

 gravel is interspersed, like the flint gravel of the plastic clay of En- 

 gland, and agreeing in character with that of the present beach. The 

 masses which have fallen on the shore, from above, look, when washed 

 by the waves, exactly like a rock abandoned by the sea for merely 

 a few tides, in consequence of the fresh appearance of the shells and 

 corals with which they are covered. 



In the tertiary rock of the neighbourhood, specimens were met 

 with, in which the calcareous matter of the shells had been replaced 

 by sulphur, and the author conceives the change to have been ef- 

 fected through the percolation of water, of which a stream exists, con- 

 taining a strong solution of sulphuret of iron with excess of acid. 

 Near this spot, called Solfarata, are some pits, apparently in the 

 upper sand, and from which sulphur is dug in winter. 



A letter from Sir Robert Smirke was then read, forwarding an- 

 other from Mr. Edge to himself, in which the latter states, that when 

 engaged in erecting some works in the neighbourhood of St. Peter's, 

 Guernsey, he found it necessary to have a well dug. At the 

 depth of 4.5 feet from the surface, the workmen came to a block of 

 granite, which they were forced to blast, and ascertained to be 6 feet 

 in thickness. A few feet beneath the granite, they were surprised at 

 finding a small quantity of peat, with several pieces of fossil timber 

 (specimens of which have been sent to the Society) in the state 

 of bog-wood, and conceived to be oak. 



The reading of a paper was afterwards commenced " On the Fos- 

 sils of the Eastern Portion of the Great Basaltic district of India," by 

 J. G. Malcolmson, Esq., F.G.S., of the Madras Medical Establish- 

 ment. 



