22 



GLACIAL DKIFT. 



Upper 

 Gallery, 



92. 



Table-case „ 

 n ltecess 41.,/ < 



SUBANGULAR SMOOTHED AND SCRATCHED STONE, from 



Anglesea ; underlying bed containing tooth of a horse (Equus 



Rounded Waterworn stone, op quartz rock, 



similar to the pebbles of the New 



perhaps derived from it ; same locality as" above. ' TWs 

 stone, though well waterworn, (unlike the pebbles of the New 

 red sandstone in place), shows traces of glacial scratching. 



93 and 94. — Rounded waterworn striated grit stones • 



Patricrqft T * • ~ 



The striations of these stones run in the direction of their 



Mr 



length. 



95 - — Angular boulder of striated grit, from the lower 

 drift boulder clay of Happisburgh, Norfolk Presented by 

 the Rev. John Gunn. 



96. 



•Fragment of large scratched and striated sep- 



Kimeridge clay, from the tipper drift 



clay, near Burgh Castle, 

 J. Gunn. 



Presented by the Rev. 



This specimen, especially, clearly indicates the production 

 of strongly striated and scratched surfaces on boulder 

 stones imprisoned in drifting ice that grated along rocky 

 coasts or sea bottoms ; for the Kimeridge clay, from which 

 this stone was probably at first derived, lies in England in 

 the form of low plains. 



97. — Same as 94 and 95. 



98.— Fragment of boulder, from the Permian brecciated 

 conglomerate, near Hundred House, Abberley Hills. 

 Placed for comparison. 



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