528 THE JOURNAL OF GEOLOGY. 



glacier, and to observe further that they are very subordinate 

 elements in the great Pleistocene glacial deposits. 



3. Products of the mechanical action of the edge of the ice. 



(1) Push moraines [a variety of terminal moraines). — The 

 distinctness of this familiar variety will doubtless be sufficiently 

 recognized without further remark. It is perhaps, however, 

 worthy of note that two sub-varieties may be recognized based 

 upon the glacial or non-glacial character of the material involved, 

 since the latter variety is sometimes overlooked. 



a. The first and common variety is formed of glacial material 

 which may belong either to the subglacial, englacial, or super- 

 glacial variety, or it may be formed of glacio-fluvial or glacio- 

 natant material. It must, however, be presumed to have been 

 previously brought forward to the edge of the ice or beyond it, 

 and to be thus subject to be plowed up or pushed up into ridg- 

 ings by the thrust of the advancing ice, which is the essential 

 factor in the formation. 



b. The second variety embraces local material of any kind 

 that lay in the path of the advancing edge of the ice and was 

 pushed into ridges by it. It is non-glacial material except in the 

 simple fact that it was ridged by ice action. It is entitled to be 

 regarded as a moraine so far as its origin as a topographic form and 

 a re-arranged formation are concerned. In other senses it is not. 



(2) Lateral moraines. — These familiar forms need no dis- 

 cussion. 



N. B. Interlobate moraines form a variety of terminal mor- 

 aines and not, as is quite often stated erroneously, a variety of 

 lateral moraines. They are produced along the line of contact 

 of adjacent glacial lobes, but the direction of ice movement is 

 perpendicular or approximately perpendicular to the moraines, and 

 not parallel with them. The mode of ice action involved in their 

 production, and the nature of the morainic aggregation resulting, 

 is that of the terminal and not that of the lateral moraine. These 

 interlobate moraines may belong to either of the three classes 

 above designated — the dump, the push, or the lodge moraine, or 

 they may be formed of the three combined. 



