GLACIER TYPES OF A WANING GLACIATION 387 



The above classification is one depending directly upon glacier 

 nourishment, and hence also upon size, and upon the stage of the 

 glacial hemicycle. In order to determine the type of any gla- 

 cier it is necessary to know the outlines of the mountain valley 



o T I 



I.I 



z milt* 

 I 



FIG. 414. Outline map of the Asulkan glacier in the Selkirks, a typical horseshoe 



glacier. 



its divide and those of the glacier or glaciers within it. It 

 is likely that the types of the advancing hemicycle of glaciation 

 would be much the same, save only for the new-born or nivation 

 glacier, which would be as different as possible from the horse- 

 shoe type, to which in size it corresponds. Upon the continent 

 of Antarctica, where the absence of any general melting of the ice, 

 even in the summer season and near the sea level, introduces special 

 conditions, some additional glacier types are found, which, how- 

 ever, it is not necessary that we consider here. 



The inherited-basin glacier. It may be, however, that gla- 

 ciers have developed, not upon mountains shaped in a cycle of 

 river erosion, nor yet in succession to an ice cap, as in the nor- 

 mal cases which we have considered. On the contrary, glaciers 



