Published online by Cambridge University Press: 01 May 2009
Twenty-One years ago Dr. Flett in a valuable paper (Trans. Edin. Geol. Soc, vol. vii, 1897) described an exceedingly beautiful hypersthene andesite from the volcanic series of the Lower Old Red Sandstone at Dumyat in the Western Ochils. In the following brief communication I propose to give a short petrographic account of a strikingly similar rock that has occurred to me in the field in a more easterly portion of the same range of hills and which is of the same geological age.