364 Dr. C. Callaway — Metamorpluc Area hi Shropshire'. 



the village, at a distance of three furlongs, there is another outcrop, 

 of which I could not with certainty determine the strike. Some of 

 the schist here is very quartzose. The last locality to be noted is iii 

 a field about six furlongs to the west-north-west of Eushton. This 

 is the best section, for we can ascertain the dip, which is at a high 

 angle to the west-south-west. It will be noted that all the strikes 

 vary between north-west and north. 



The rock is similar in all these localities. It is a fine-grained, 

 quartzose, mica-schist. Some of it might, indeed, be called quartz- 

 schist. It is not exactly like any rock I have yet met with, but 

 its nearest analogue is the quartz-schist of Durness and Tongue. 

 It is, however, of a still finer grain than the Sutherland type. 



Prof. Bonney has been kind enough to examine a series of slides 

 cut from rocks typical of the localities named above. The following 

 is a summary of his conclusions, extracted by me from his rough 

 notes. 



Bitshton (134). — This rock is mainly quartz and a green mineral, 

 which is probably an alteration product after a magnesian mica. 

 There are also a hydrous white mica, epidote, and replacements after 

 felspar. The rock is very distinctly foliated. It is a mica-schist of by 

 no means a very modern type. 



Three furlongs ivest of Bushton (135). — Constituents similar to 

 last, but rather more minute. Aspect more modern. The rock 

 suggests some of the upper group of Alpine schists (" schistes 

 lustrees" of Lory) and of the newer gneisses of Scotland, e.g. part 

 way up Glen Docherty. 



Tivo furlongs north-north-ivest of RusJiton (136). — Similar, but con- 

 tains some irregular clusters of small light-coloured garnets, seem- 

 ingly partly replaced by a chloritic mineral. Well foliated, but not 

 banded. It is either one of the same group of rather late schists, or, 

 just possibly, an older metamorphic rock crushed in situ. 



Six furlongs west-north-west of Bushton (137-139). — Nos. 137 and 

 138 are rather similar to 135. No. 137 is traversed by more definite 

 (but very thin) mineral bands. The larger grains of 138 are even 

 more suggestive than 135 of a fragmental origin. One of the grains 

 shows the striping of a plagioclastic felspar. The rock, however, 

 is distinctly metamorphic, and this is more evident under high 

 powers. No. 139 is also metamorphic. 



I may state that the resemblance between the Eushton rocks and 

 some of the newer of the Highland schists was noticed by me in the 

 field before I sent specimens to Prof. Bonney ; at the same time I 

 am quite prepared to admit the possibility of his suggestion that 

 No. 136 is an old gneiss crushed in situ ; and if it is so, I know no 

 reason why the whole mass of schist should not be placed in the 

 same category. The facts which lend some support to this view are 

 the following : — 



(1) The strike of the Eushton schist is in the same direction as 

 that of the gneiss of Primrose Hill, whereas in the Highlands the 

 strikes of the older and the younger gneisses are widely discordant. 

 Too much importance, however, must not be attached to this coin- 



