346 Proceedings of the Boyal Physical Society. 



there is a marked absence of such accumulations through- 

 out the area occupied by this deposit, as noted by Mr 

 Jamieson. 



Between Dalnawillan Lodge and Altnabreac Station, we 

 observed moraine heaps composed of the same material as 

 the mounds at the former locality. Over much of the moor 

 also there is an irregular covering of gravelly material ex- 

 posed in pits, which may belong to the same series. In 

 Strathmore we observed the same material in places where 

 no mounds could be seen, which leads us to believe that this 

 covering may have been deposited by flood waters from the 

 melting ice. 



Again, on the moor to the west of Loch Shurrery, moraine 

 heaps occur, and by the roadside leading to Loch Scye pits 

 have been dug in coarse gravelly and rubbishy material, 

 which evidently belongs to the same formation. 



In the Braxside burn, which drains the western slopes of 

 Ben Rah, south of Reay, moraines may be seen extending 

 across the valley, and they occur at intervals on the moor 

 northwards to Sandside. But to the west of Eeay, in the 

 direction of the county boundary, similar deposits are irregu- 

 larly distributed over the slope. They increase in number 

 and in size on the col and along the slope towards Strath 

 Halladale, in the county of Sutherland. Indeed, the deposits 

 of the later glaciation in this strath are grandly developed. 

 The bottom and sides of the valley are covered with groups 

 of moraines, displaying at some points a marked concentric 

 arrangement. Numerous Uocs 'perches are strewn on these 

 mounds, composed of granite and granitic breccia. The 

 material consists of a compact stony and rubbishy matter, 

 gravelly in some places and clayey in others, with sub- 

 angular and rounded stones, few of them being striated. 



Now, it is interesting to note that while the traces of the 

 later glaciation overlap on to the grey shelly boulder clay at 

 Dirlot, they do not reach the outer limit of the red boulder 

 clay at Reay. Taking Shebster as the boundary line between 

 the two boulder clays, the later morainic deposits " tail off" 

 about three miles from this limit. But when we think of 

 the large tract of country between Reay and Strathmore over 



