. Fig. II. Section of phyllite, showing folding. Another specimen shows many points of resemblance to the above-described series, especially in the abundance of argillaceous material and the presence of calcite, epidote and sericite. It differs, however, in that some of the folia are rich in large, angular fragments of alkali-feldspars, including orthoclase and albite, which are still comparatively fresh. This may perhaps be best interpreted as a sheared rhyolitic tuff, intermingled with normal sedimentary material. The remaining three stones of the metamorphic group are quartz-epidote-amphibo
. Fig. II. Section of phyllite, showing folding. Another specimen shows many points of resemblance to the above-described series, especially in the abundance of argillaceous material and the presence of calcite, epidote and sericite. It differs, however, in that some of the folia are rich in large, angular fragments of alkali-feldspars, including orthoclase and albite, which are still comparatively fresh. This may perhaps be best interpreted as a sheared rhyolitic tuff, intermingled with normal sedimentary material. The remaining three stones of the metamorphic group are quartz-epidote-amphibole-schists which have probably been derived from basic igneous rocks or their tuffs. One is a quartz-albite-tremolite- epidote-schist; the other two are calcite-quartz-glaucophane-epidote-schists. The first is a fine-grained, apparently bedded rock with a schistosity coinciding with the bedding planes. It consists mainly of a mixture of minute grains of epidote with microlites of albite, and prisms of colourless to pale green tremolite which have a tendency to lie athwart the planes of schistosity. This material carries large and small folia consisting of quartz and albite, both enclosing innumerable needles and thin plates of tremolite. The albite often forms large, simply twinned, blasto-porphyritic crystals developed in a mosaic of quartz and small albites. The largest and coarsest of these folia has a distinct resemblance to an aplite vein. This rock is somewhat difficult to interpret,
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