IN a previous paper in this Magazine, as well as in an official report to the Government of the Federated Malay States and in a paper in the Mining Magazine, I have discussed in some detail the geological relations of the pregranitic sedimentary rocks of the Kinta Valley, in the State of Perak, F.M.S.1 The relations of the mainly calcareous Raub Series of Permo-Carboniferous age and the rocks generally known locally and colloquially as the “ Schist Series ” (Triassic and perhaps Rhaetic), formed one of the principal subjects on which I was requested to report to the Government. My conclusions were, I think, sufficiently clearly expressed in the publications quoted, and it is unnecessary to repeat here the arguments and field evidence which led me to those conclusions.