On a Peculiar Variety of Hornblende from Mynydd Mawr, Carnarvonshire
Prof. T. G. Bonney1
1After this paper was written, but a few days before it was read, an interesting article, by Mr. A. Harker, appeared in the Geol. Mag. for May 1888. As, however, the two papers treat the subject from somewhat different aspects, I have left unaltered that part of my own which is common with his.