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which distinguishes them from the rougher ridgings and sharper 

 contours of frontal moraines formed by the mechanical thrust of 

 the ice, or by the dropping of superglacial material at its edge. 

 [a) Submarginal or lodge moraines (a variety of terminal 

 moraines). — The most important form falling under the above 

 head may be designated submarginal or lodge moraines. They 

 are designated submarginal, not so much because they are 

 believed to be formed near the edge of the ice and not abso- 

 lutely at its edge, as because they are believed to be formed 

 wider the margin of the ice. Three varieties of moraines, all of 

 which may be called terminal, are recognized, being produced in 

 three distinct ways. The first are formed from material borne on 

 or in the ice (the latter being brought to the surface by ablation 

 before reaching the edge) which is dropped at the terminus of 

 the ice and which, when the ice remains stationary for a sufficient 

 period, grows into a bordering ridge. These may be given the 

 rather homely but expressive name dump moraines. The second 

 is formed by the mechanical thrust of the ice when it advances 

 against any incoherent material that lies in its path. These may 

 be designated push moraines. The third variety consists of that 

 under consideration, and which may be designated lodge moraines, 

 from the conviction that the material, instead of being carried or 

 pushed or dragged forward to the extreme edge of the ice, is 

 permitted to lodge under its thin border, and constitute a sub- 

 marefirial accumulation. The lodge moraine is not in its nature 

 or material radically different from the ground moraine which 

 lodged farther back from the edge of the ice, and constitutes the 

 subglacial till sheet. It differs from it, perhaps, only in the fact 

 that the thinned and weakened edge of the ice presented con- 

 ditions specially favorable to deposition, and that, as a result, a 

 thickened belt of drift formed under the border of the ice when 

 it remained approximately stationary for a sufficient period and 

 took on the special billowy contours above described. The sub- 

 marginal moraines were doubtless subjected to more or less 

 mechanical action of the ice as it oscillated forward and back- 

 ward. This action is thought to have been of the nature of an 



