Beacon Cliff, and Barton Cliff, Hampshire. 289 



b. Black carbonaceous clay with lignite, from one to five inches. Thickness of No. 5. about 

 1 foot. 



6. «. Green unctuous marls without shells, four feet. In some places, as near Long-Mead. End, 



this marl hardens into green stony concretions, which, when exposed, acquire a ferrugi- 

 nous colour, and are seen projecting from the cliff or strewed along the beach. 



b. Green arenaceous marl, in some parts passing into a pure white siliceous sand. The two 



shells which occur in great abundance in this stratum are mya plana (Min.Con. tab. 76. 

 fig. 2.) and a species of potamides. Besides these are found melanopsis brevis, two spe- 

 cies of cycias, a neritina, fragments of helix lenta (Brander), a small cylindrical serpula, 

 and also shining lozenge-shaped scales of fish ? Gyrogonites also (chara Medicaginula) 

 abound in some of the sandy portions of this stratum in Beacon Cliff. This bed is about 

 two feet and a half thick. 



c. Beds of pure white sand and argillaceous sand. These are characterized by a layer of 



sand filled with a potamides like P. margaritaceus (Min. Con. tab. 339. fig. 4.), 

 accompanied by mya plana ; the latter in a very perfect state with both valves. Har- 

 dened blocks of this sand lie on the beach, containing the potamides in abundance. A 

 species of mytilus also occurs (M. Brardii, Min. Con. tab. 532. fig. 2.), and one from 

 hence has a small serpula attached, which is cylindrical, with two ridges. These beds 

 are from 8 to 10 feet in thickness. Melania conica (Min. Con. vol. 6, p. 60.) (bu- 

 limus conicus Brard.) is also abundant with the above. Total thickness of No. 6. about 

 15 feet. 



7. a. Light green marl, containing mya subangulata and a planorbis, 3 feet thick. 



b. Dark arenaceous bed, sometimes argillaceous. In this are found helix or paludina 



lenta (Min. Con. tab. 31. fig. 3.), mya subangulata*, melanopsis brevis (Min. Con. 

 tab. 523. fig. 2.)5 a- small planorbis, a new species of ancylus, A. elegans (Min. 

 Con. tab. 533.) ; with many minute shells, apparently the young of some of the pre- 

 ceding : also small smooth shining black capsules, of a plant nearly spherical, hollow, 

 lined with a membrane, the integument composed of minute cells. 2 feet thick. 



c. Light green marl with a layer of bluish sandstone, 4 feet. 



d. Carbonaceous clay and lignite, 6 inches. 



e. Light green marl, 2 feet. 



/. Carbonaceous black clay, 6 inches. 

 g. Sandy loam, 3 feet. 

 A. Reddish brown clay, 3 feet. 



i. Light green loam ; in lower part univalves (helix lenta?) and gyrogonites (chara Medica- 

 ginula), 7 feet. Total thickness of No. 7, about 22 feet. 



8. a. Green marl ; bivalves in the upper part, 5 feet. 



b. Coal-black carbonaceous clay and lignite, 6 inches. 



c. Black mould resembling bog-earth, 6 inches. 



d. Ferruginous clay. In this is a species of cycias, the same as one of those noted in 6 b., 



fragments of a mytilus resembling crenatus, mya subangulata, and fragments of an uni- 

 valve, 6 inches. 



* Mr. J.Sowerby considers it not improbable that this shell may be the young state of mya plana. 



2p2 



