686 PROCEEDINGS OF THE GEOLOGICAL socilETy. [June 22, 
fjord. In concluding what I have got to say regarding the sub- 
glacial rivers, I cannot help remarking that the effect of this great 
ice-covering over Greenland must be to thoroughly denude any soft 
sedimentary strata which might have reclined on the underlying 
igneous rocks at the time when the whole country got so over- 
spread. Now we know that during the later Miocene epoch the 
country supported a luxuriant vegetation, as evinced by the remains 
which I and others have collected from these beds’. I was struck, 
when studying this subject in Greenland, with the fact (though I 
have no desire to push the theory too far) that the only places 
where I did not see former ice-action were the very localities where 
these Miocene beds repose. ‘These localities are a very limited 
district on either side of the Waygatz Strait, on Noursoak penin- 
sula, and Disco Island, neither of these localities having apparently 
been overlain at any time by the great inland ice. Noursoak penin- 
sula juts out from the land, and only nourishes small glaciers of its 
own; and Disco Island is high land, possessing a miniature inland 
ice or mer de glace, with defluent glaciers of its own. If the great 
inland ice had ever ground over this tract, I hardly think it possible 
that the soft sandstone, shales, and coal-beds could have survived the 
effects of this ice-file for any length of time. 
5. The Moraines.—Moraines are usually classified as lateral, 
median, terminal, and profonde’, or under the glacier. From the 
simple character of the Greenland. glacier, as described, it will be 
readily seen that the median moraine, formed by the junction of 
two lateral moraines, must be rare, while the terminal takes, ex- 
cept in rare instances, another form. Ordinary alpine glaciers, 
when grinding down between the two sides of a monntain-gorge, 
get accumulated on their sides rubbish, such as earth, rocks, 
&e., which fall either by being undermined by the glacier, by 
frost, or by land-slips, until two lateral moraines are formed. If 
the glacier anastomoses with a second, it is evident that two of the 
lateral moraines will unite in the common glacier into a median one. 
When the glacier terminates, this moraine carried along with it, 
is deposited at its base, and forms the terminal moraine. Over the 
lower face of a glacier, according to the heat of the day, some ma- 
terial is always falling, a thimbleful of sand, it may be, trickling 
down in the stream of water; or a mass of stone, gravel, and earth 
may thunder over the edge. If the glacier advances, it pushes this 
moraine in front of it, or, it is possible, may creep over it and carry 
it on as a moraine profonde. This moraine profonde consists of the 
boulders, gravel, &c., which the glacier, grinding along, has carried 
with it, and which, adhering to its lower surface, help to grind 
1 Heer, in the ‘Philosophical Transactions, 1869, pp. 445-488. In this 
treatise of Prof. Heer I have printed a few notes on the geology of these Mio- 
cene beds ; but, owing to an accident, I did not see them in proof. Hence there 
are several errors. ‘The title of the paper is also apt to mislead. These geolo- 
gical and ‘other points I hope in due course to correct in a full account of the 
geology of the Waygatz Straits, with illustrative sections, sketches, &c. 
? The term moraine profonde was first used by Hogard in his ‘Coup d’eil 
sur le terrain erratique des Vosges’ (1851), p. 10. 
