S. V. Wood,jun. — American and British Surf ace-Geology. 483 
which there seems no evidence, tlie only fossil organisins which 
oocur in the deposits of the lake-basin being those of land or fresh- 
water. So far as I can understand the case, however, there seems to 
me no necessity to infer any depression until after the formation of 
beds Nos. 1 and 2, as the phenomena indicated by these beds seem 
explicable by returning warmtb alone, and by the draining off of the 
lake-waters after the deposit of No. 1; while the marine clays of the 
Lower St. Lawrence, which, so far as I have been able to gather the 
facts of American geology, alone afford evidence of any submergence 
of the St. Lawrence basin, seem to me, as subsequently explained, to 
belong to a later glaciation. 
Prof. Newberry contends that the lower and unstratified portion 
of the Erie clay represents the material eroded by the glacier, which, 
as the ice-sheet retreated northward, it thrust out and left behind ; 
and which now forms a nearly continuous sheet of Boulder-clay over 
the glaciated surface. He urges that this clay was not deposited 
beneath the glacier-ice, because it covers the glaciated surface in a 
sheet sometimes 100 feet thick, and that it must have accumulated 
at the margin of the glacier as it receded. This, if we substitute the 
sea in Britain for the lake in Ohio, is in chief measure, the mode of 
origin for which I have for many years past been contending in the 
case of the Glacial clay of England, as distinguished from Mr. James 
Geikie’s view of its origin beneath the ice itself. 
There is one feature, however, connected, according to my view, 
with the origin of the unstratified Glacial clay of England to which 
I find no parallel in Prof. Newberry’s memoir, viz. the lifting of 
portions of this extruded mass, and its distribution over the bottom, 
partly from being dropped in small quantities, but principally in 
sheets or masses. This seems to me to have been clearly the mode 
of accumulation in the case of that part of the English clay which 
overlies the Middle Glacial sands, as well as of some portion of that 
part of the clay which has no Middle Glacial beneath it, but which, 
as at Dimlington and Bridlington in Yorkshire, contains witliin 
its mass beds of sand full of lamellibranchiate mollusca with 
valves in some cases united. When, however, the vast area of the 
American beds comes to be examined with the same minuteness as 
has been the case with the comparatively small area of the British, 
I do not doubt that parallel features will be found in them, unless 
the water under which the moraine was extruded was too deep to 
allow of this process. 1 
1 If, as some American geologists say, unstratified morainic clay has been found 
overlying the forest surface in situ, then these would seem to me to be instances of 
dropping from floating ice ; for if the ice passed over the forest, it must have destroyed 
it. Some of our ^Norfolk geologists are now coming to the opinion that the long- 
known Forest-bed of Cromer is not in situ, but transported ; and if they are right, 
the theories hased upon the occurrence of peats and freshwater shells in the midst 
of Glacial clay will require much reconsideration. This, however, does not apply 
to the Pakefield and Kessingland root-indented hed, which is clearly in situ. If 
it should tum out that the Cromer Forest and freshwater deposits associated with 
it are not in situ, but stripped from some distant land-surface by ice, and transported, 
analogv for such a thing may he found in some peaty masses which I have observed 
imbedded in the midst of the marine-formed Contorted Drift in the Cromer cliif 
itself. 
