BEMBRIDGE MARLS. 179 



the subdivision, from the Bembridge Limestone forming Ham- 

 stead lodge to the "Black Band" which constitutes the base of 

 the Hamstead Series, may be examined in detail at low water 

 without a break, as they successively crop out on the shore, and 

 their beautifully preserved fossils may there be collected. 



The following section taken along the shore, at low water, in 

 1856, by Sir A. Ramsay, then Director of the Geological 

 Survey, Professor John Morris, and H. W. Bristow, is more 

 complete than that of Professor Forbes, in consequence of its 

 supplying the thicknesses of the several beds, which are omitted 

 in his section. 



Bembridge Marls of Hamstead 

 Measured along the Shore at Loio Water, 



Black Band (base of Hamstead Series) 



Green clays, with large bands of Paludina lenta 



Ironstone ---.... 



Clay 



Clay with Paludina .-.--. 



Concretionary ironstone ..... 



Clay with Paludina ...... 



Clay with two or three small black bands 



Ferruginous brown sandy clay, with Paludina at base, thick- 

 ness variable . - - - . OtoOG 



Thin bituminous bands, with reed-like plants, and a layer of 



Paludina lenta below filled \vith green clay - - 1 



Grey clay, with short zones of Melania Forbesii and nodules 



containing Paludina lenta - - - . - 3 



Band of scattered nodules of iron pyrites, overlying verdigris- 

 green clays, with bands of Paludina lenta (occasionally of 

 very large size), Melania Forbesii - - - - 5 



Dark-grey clays, with Paludina and numerous oval seed- 

 vessels, and containing thin carbonaceous sandy bands, with 

 (reed-like) plant impressions, Cypris, Paludina, Planorbis 

 immediately overlying a layer of large Limnaa. This is 

 altogether a freshwater deposit - - - - 3 



Bands of Melania turritissima, Planorbis, and Paludina - 1 



Greenish shaly clay, with concretions of indvirated marl, and 

 containing near the base a band o£ Melania turritissima, 

 M. costata, Melanopsis carinata, Paludina, Sfc. - - 4 



Hard shelly band chiefly made up of Melania turritissima, a 



few Melanopsis, and fragments of Fish - - - 3 



Pale-grey clay, with bands of compressed shells, chiefly 



Paludina - - - - - - -20 



Sandy band, full of Cyrena obtusa (with both valves), 



Ceritliium and Melanopsis fusiformis - - - 9 



Pale greenish shaly clay, with a thin band of Melania turri- 

 tissima 6 inches from the top, and a 1-inch bituminous 

 band at 3 feet. Compressed Carpolithes, Melania turri- 

 tissima, Melanopsis carinata - - - -60 



M 2 



