throughout the northern hemisphere on both sides of the Atlantic, the stratified drift of the glacial period is very commonly devoid of fossils, in spite of the occurrence here and there, at the height of 500, 700, and even 1,400 feet, of marine shells. These, when met with, belong, with few exceptions, to known living species. I am therefore unable to agree with Mr. Kjerulf that the amount of former submergence can be measured by the extreme height at which shells happen to have been found.
Glacial Formations in England.
Fig. 38
The mountains of Cumberland and Westmoreland, and the English lake district, afford equally unequivocal vestiges of ice-action not only in the form of polished and grooved surfaces, but also of those rounded bosses before mentioned, as being so abundant in the Alpine valleys of Switzerland, where glaciers exist, or have existed. Mr. Hull has lately published a faithful account of these phenomena, and has given a representation of some of the English 'roches moutonnées,' which
- ↑ Edinburgh New Philosophical Journal, vol. xi. pl. i. p. 31, 1860.