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ders of Brockram from the head of the valley, Ennerdale Syenitic 

 Granite, Galloway Granite, and a variety of other rocks transported 

 in a diametrically opposite direction, while from directions trans- 

 verse to these came boulders of Whin Sill, Dufton Granite, and 

 Roman Fell Conglom orate from the Cross Fell Escarpment on the 

 one hand, and representatives of the Older-Palaeozoic rocks from 

 various parts of the Lake District, St, John's Quartz Felsite, Shap 

 Granite and Mardale Gabbro, on the other. While the ice was 

 still moving up the valley, under the pressure of larger accumula- 

 tions on the west, the combined effect of the waste of its upper 

 surface under atmospheric influences and the turgesence of the 

 whole, consequent upon the general level being maintained by the 

 downflow from the thicker ice to the west, tended to bring any 

 substances included in the ice nearer and nearer to the surface, at 

 whatever elevation that may have had there. 



Envelopment and transportal of Organisms. — None of the ice 

 around Penrith ever included any considerable proportion of 

 marine organisms ; for, if I read its history aright, the sea bottom 

 of the Sohvay had been scoured clean out, by the outflow of large 

 glaciers moving seawards for long periods before the Ice Barrier 

 crept so far south. When this did reach the North Channel and 

 the ice within the Solway Basin was diverted inland, the confluent 

 glaciers carried with them nothing but terrestrial and subglacial 

 debris. But the case must have been otherwise with the parts of 

 the Irish Sea further south. Here the ice must have traversed a 

 sea bottom overspread with various older deposits containing the 

 remains of organisms pertaining to the various colonies of Celtic, 

 Lusitanian, Boreal, and Arctic species that had successively obtained 

 stations there as the changes of their environments favoured the 

 encroachment of the animals of one province or of one bathymetrical 

 zone* upon that of another {Geol. Mag., 1874). 



* My colleague, Mr. Clement Raid, has reminded me of the importance of this 

 point in its bearing upon the origin of shell beds of glacial origin. It would by no 

 means follow that, when once such organisms had worked their way ittto the ice 

 that the onward movement of the mass would result in the crushing of the shells. 

 What we know of the behaviour of bodies entombed in modem glaciers would 



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