Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/277

 constituted a portion of Schihallien and of the northern side of Glen Lyon, terminating in the micaceous and chlorite schist of the ridge of Ben Lawers. Taking it up now from Blair we shall find it occupying a large proportion of the whole group of hills which lies between the Bruer and the Tilt, lying over the granite and stretching away towards Glen Dee, and thus uniting with that tract of it which I also described last year as skirting the great granite mass of the Grampians towards its eastern declivity. Returning again to Blair it is found extending over the whole ridge of Ben Gloe, and here it scarcely ever alternates with schist. From Ben Gloe it may be traced over the Scarsough into Mar, forming at the same time Cairn ree and a considerable extent of the hills which skirt Glen Femat and Strath Airdle to the eastward. From Mar it is then seen to form a principal portion of the tract which bounds Glen Shee on both sides, but further into the hills of Angus I have had no opportunity of following it. If the several spaces which I have described here and in the former paper, be marked on the map, it will be seen to occupy a very large portion of the country, and one which will I doubt not be easily extended. I do not mean to lay it down as a rule, (since the irregular position of this class of rocks is such that they scarcely admit of any rule), but I think it will he found here most abundant in the vicinity of the granite, while the micaceous schist on the contrary lies at the greatest distance from it. A mineralogical map of Scotland, a work as yet far distant, will probably confirm the generality of this remark.

I have but little to add to the particular description of the rock and of its several varieties given in the above named paper, but there are a few circumstances worthy of record.

In Ben Gloe it is found incurvated and contorted in the manner of micaceous schist, a proof that, like all the other schistose rocks