TRANSACTIONS OF THE SECTIONS. 87 



occurrence of marine remains covering the bones of land animals in 

 Cefn Cave, in Denbighshire, on which he has also presented a memoir 

 to the same society. 



The principal deposit of bones lies beloio the level of the entrance, 

 and beneath one if not more than one crust of stalagmite. The bones 

 in this lower deposit are accompanied by rounded pebbles of grauwacke, 

 slate, and limestone. The surface of the upper mass of marl, with an- 

 gular pieces of limestone and bones, is covered by a deposit of sand, 

 divided by a few inches of finely laminated marl, and in this sand, the 

 total thickness of which, including the marl, does not exceed 18 inches, 

 are fragments of marine shells. These fragments are small and not 

 very numerous, but they are not smaller than a considerable portion of 

 the fragments dispersed through the northern drift which covers the 

 surface of the neighbouring country. At the extremity of the exca- 

 vations in the cave, this sand is covered by a thin film of stalagmite. 

 No marine remains were found in any other part of the cave, nor were 

 any perforations of lithodomous shells seen on the sides. 



On the Shells of the Newer Pleiocene Deposits. By James Smith, 

 F.G.S., of Jordan Hill. 



The author communicated the result of a comparison made by him 

 between the marine shells found in elevated stratified deposits belong- 

 ing to the newer pleiocene tertiary formation of the British Islands, 

 with those now existing in the adjoining seas. Out of 176 species, 92 

 per cent, were recent, and 8 per cent, extinct or unknown. 



On Vertical Lines of Flint, traversing Horizontal Strata of Chalk, 

 near Norivich. By C. Lyell, F.R.S., G.S. 



It has long been known that near Norwich the horizontal beds of 

 flint nodules in the white chalk are crossed by perpendicular rows 

 of much larger flints, often several yards in height. These larger and 

 vertical flints are provincially called potstones, and are the same as 

 those which occur in the chalk of Ireland, and are described by Dr. 

 Buckland under the name ofparamoudra. At a place called the Grove's 

 End House, near Horsted, about six miles from Norwich, an excava- 

 tion has been made, from 15 to 20 yards wide, and nearly half a mile 

 in length, through 26 feet of white chalk, covered by strata of sand, 

 loam, and shelly gravel, about 20 feet thick. In the chalk thus in- 

 tersected, the rows of potstones are remarkable for their number and 

 continuity ; it is affirmed by those who for more than twenty years 

 have superintended the cutting of the canal, that every row of upright 

 flints has been found to extend from the top to the bottom of the 

 chalk, so far as the excavation has been carried downwards. The 

 rows occur at irregular distances from each other, usually from 20 to 



