GLACIAL DEPOSITS. 31 



DISTRIBUTION OF THE TILL. 



The cleptb. of the till varies greatly. Numerous small areas are bare of 

 it. More often these bare places are in the valleys or on the tops of hills, 

 especially in the slaty regions. No account is here taken of the areas of bare 

 ledges near the sea, denuded by the Avaves, or of steep hillsides, denuded by 

 landslides. In many places bowlders are arranged in trains, presenting the 

 appearance of the moraines of modern valley glaciers. I have elsewhere 

 described several terminal moraines, most of which appear to have been 

 formed in the sea at the extremity of the ice at a time when the ocean stood 

 at a higher level than now. So also there are masses of till of various shapes, 

 mostly short ridges and irregular heaps, found in low depressions of the 

 higher east-and-west ranges, or bordering these passes. They are more 

 numerous on the north than on the south slopes of the passes. Such passes 

 and low cols would for a time during the decay of the ice-sheet afford exit 

 southward for tongues of ice after the glacier had become too thin to permit 

 flow over the higher hills. These heaps have not so steep slopes as the ordi- 

 nary terminal and lateral moraines of mountain glaciers have, and tlie shapes 

 of the morainal masses deposited by glaciers bearing matter which fell on 

 them from above are evidently different from those into which the moraine 

 stuff was incorporated from beneath, if we except the extreme terminal 

 moraine. It is an interesting study to determine whether thick masses of 

 euglacial till can be accumulated within the ice by ice movements. The 

 term moraine was first definitely applied to masses that accumulated on the 

 surface or at the extremity of the ice. It has also been applied to the mat- 

 ter beneath the ice. Can it properlj^ be applied to a mass of the ground 

 moraine of unusual thickness or to similar masses of euglacial till ? In this 

 report I have not applied the term moraine to masses of till unless they 

 present the external and internal characters of the moraines found on the 

 surface or at the extremities of ordinary living glaciers ; except that ground 

 moraine is used as a generic term to indicate the whole of the subglacial till, 

 but not individual masses or accumulations of it. 



In the hilly ])arts of the State the phenomena of "crag and tail" are 

 well exhibited. This term refers to the accumulation of till which collected 

 in the lee south of projecting hills, especially conical peaks. These accu- 

 mulations consist of ridges or deep sheets of stonj^ till, generally of loose 

 structure and rather easilv eroded by sjjrings and rains. 



