322 MK. J. B. HILL Olf THE [^^g. I9OI, 



a bed of this nature, varying from 2 to 6 yards in thickness, rests upon 

 the limestone more or less horizontally. In this bed the long edges 

 of the folded limbs and detached fragments are in alignment with 

 the strike of the foliation and of the folding axes of the district, so 

 that we have, in cross-section, a series of closely-packed lenticles 

 standing on edge, bound together by a limestone-matrix. The 

 junction, however, of this composite mass with the limestone below 

 is not sharp ; blocks of igneous material are seen included in the 

 limestone for some yards from the epidiorite-mass, some of which 

 are well rounded, while near the top of the limestone, and below 

 the composite bed, some solid blocks of epidiorite occur, 2 or 3^ 

 feet across, which have not been broken down into lenticles. On 

 the north-western corner of the hill the limestone contains boulderS' 

 of epidiorite, perfectly rounded, ranging in size from afoot downward, 

 extending to some distance from the epidiorite-mass and considerably 

 below it. An examination of these boulders shows that they belong, 

 to the vesicular type of epidiorite which reposes on the limestone,, 

 but most of them are considerably fresher and more compact, the 

 fresh compact varieties showing no foliation. Boulders, however^ 

 do occur of the more decomposing type, which is the prevalent 

 feature of the parent mass. There seems, on the whole, to be some 

 grounds for assuming that the crush- conglomerates are anterior to 

 the foliation, and that the boulders largely escaped deformation 

 owing to the relative plasticity of the limestone -mass in which they 

 are enclosed. Boulders of grit are also seen in the limestone, but 

 these are evidently derived from a grit-band which is sometimes 

 seen to abut against that mass. 



Another example may be cited. On the steep scar-face, near 

 Creagantairbh, a junction is seen of a massive epidiorite and a 

 limestone, where the junction-rock for many yards is intimately 

 interfolded, the folded bands ranging from 5 or 6 inches or more in 

 width, down to tiny films. Some are more or less continuous, while 

 others have been so far isolated that the rock simulates the appear- 

 ance of a compressed Boulder-bed, with the fragments all steeply 

 inclined and lying in one direction, but without having been rounded.. 

 The limestone is of the same coarse gritty type as at Creag nam 

 Fitheach, and the igneous lenticles show clearly the small felspars.. 

 Another limestone-exposure adjoining, contains detached blocks and 

 angular boulders of the epidiorite, while a little farther removed an 

 isolated well-rounded boulder of epidiorite was seen in the limestone. 

 Close to these exposures some thin strips of limestone occur, con- 

 taining rounded inclusions of quartzite exceeding 1 inch in diameter, 

 and boulders of the epidiorite which bound the limestone. These 

 igneous boulders contain much calcite, and some dark crystals of the 

 same mineral which is so common a characteristic of the limestone. 

 They would therefore seem to have been embedded in the limestone 

 before its final crystallization. 



Many instances might be cited where similar structures have 

 been set up near the junction of the limestone and the epidiorite^ 

 and apparently on the same stratigraphical horizon. 



