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between the muscovite-laminae. As a product of alteration finallybrown-iron-ore (limonite) is found.

Andalusite-mica-schiist. Tliis hard, distinctly schistose, reddish-gee}'rock, in which the naked eye discerns only silvery muscovite-laminae,was found as a boulder only in the Wai Milia. In the thin sectionsthe rock, of which quartz forms the principal constituent, shows acrystalloblastie structure. Numerous are likewise colourless laminae ofmuscovite, and besides those of a greenish mica. Andalusite is foundin the form of colourless prisms stringed together and in grains,whilst prisms of tourmaline scarcely ever occur. Rutile forms dark-brownish red, very strongly refractory grains and knee-shaped twins.

Mica-tjuartzile-schist. A boulder from the Wai Kabuta, a hard,grey and very tine-grained, distinctly stratified rock. Under themicroscope we perceive that quartz, which is usually accompaniedb} -nuscovite, is the chief constituent, whilst in strata of a darkercolour, but restricted to these, biotite is likewise freely spread.Moreover andalusite occurs in the form of aggregates of prisms, withnumerous ore-grains and further occasionally garnet, rutile, titanileand tourmaline.

Mica-quartzite occurs among the boulders of the Betino, a lefttributary river of the Wai Milia. In this fine-grained, reddish-greyrock numerous muscovite-laminae can be discerned by the nakedeye. As appears from tig. I the quartz individuals do not exhibit,“Pflaslerstructur” under the microscope, but they engage into oneanother like teeth. Further it must be remarked that finely distributed

Fig. 1.