B. N. Peach & J. Home — Glaciation of the Shetlands. 371 



across the Bay of St. Magnus. This direction is at variance with 

 all the strias we noted on the island which are given in the following 

 list :— 



N."W. on east side of Culla Voe — Head of the Voe. 



N. near head of Culla Voe. 



N. 6^ W. west bank of Culla Voe. 



N. 20° W. east side of Culla Voe. 



N. 20° W. ditto ditto. 



JSr. 20° W. on headland mouth of Culla Voe. 



]Sr. 20° W. \ 



N. 20° W. ! three localities at mouth of Olas Voe. 



N. 20° W. ) 



N. 28° W. west bank of Olas Voe. 



N. 20° W. on promontory about one mile east of Hamma Voe. 



N. 4° E. near previous instance. 



N. 3° W. on shore west of Bay, south of church. 



In the Boulder-clay on Papa Stour, numerons striated blocks of 

 the altered Old Red rocks are to be f(jnnd, which were derived from, 

 the area occupied by these rocks between Sandness and Bixetter 

 Voe ; thus clearly indicating that the ice which produced the striae 

 must have come from the south-east. We think it is highly pro- 

 bable therefore that, in a region where the rocks are so highly 

 metamorphosed, bands of actinolite schist may be met with along 

 the track of the Scandinavian mer de glace as indicated by the strige. 

 We noticed various blocks of hornblendic schist, of gneiss, and mica 

 schist on the island brought thither from the centre of the Mainland. 

 But even though these blocks of actinolite schist came from Hills- 

 wick Ness, it would not invalidate the evidence in favour of the 

 primary glaciation. It would anly point to a later movement at 

 right angles to the great extension of the ice. By referring to the 

 map accompanying our paper, it will be seen that we have noted 

 stria3 in the neighbourhood of Walls and Sandsting pointing towards 

 the S.W., at right angles to the older set. Where the surface is 

 " cross-hatched," the latter have been well-nigh effaced by the later 

 glaciation. By means of this later movement the altered Old Red 

 rocks were borne south-westwards on to the area occupied by the 

 Sandness granite. 



Dr. Hibbert next refers to the Stones of the Stefis, near the 

 mansion of Lunna, on the eastern sea-board of the Mainland, which 

 have been transported a mile or two in a south-westerly direction 

 from their parent source. Thereafter he notes the occurrence of 

 large fragments of serpentine and euphotide on the east coast of 

 Yell, which have been carried from the islands of Unst and Fetlar, 

 lying to the east. These examples confirm our own observations 

 regarding the south-westerly movement on the eastern sea-board 

 during the primary glaciation. The blocks of primary greenstone 

 (diabase) on Roeness Hill, which he says have been rolled in a 

 southerly or south-westerly direction up a gradual ascent of three 

 or four miles, entirely support our conclusions. These boulders, in 

 our opinion, were carried uphill by the Scandinavian mer de glace 

 in a south-west dii'ection along the lines indicated by the striae on 

 the eastern seaboard of Northmavine. The boulder on Hillswick 



