Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/182

138 at Spynie and other points at which they are seen is such as entirely to harmonize with and confirm this conclusion.

"When, however, we seek for information as to the strata which respectively underlie and succeed this formation, we find that the greatest differences of opinion prevail. Nowhere in Elginshire has the Cherty Rock of Stotfield been seen to be covered by any other beds; indeed it is the remarkable indestructibility of that stratum which, as pointed out by Sir Roderick Murchison, has led to the preservation of the several ridges of sandstone, which rise like islands in the midst of a sea of drift. Whenever it is well exposed, as at Inverugie and Linksfield, the upper surface of the Cherty Rock of Stotfield exhibits the most beautiful glacial polishing and striation. The fact that this rock is never found succeeded by any other formation in the Elgin district has been very strongly insisted upon by several authors, especially by Mr. Duff and Professor Harkness.

Similarly we seek in vain for any clear and undisputed section showing the Reptiliferous Sandstone in overlying contact with any other rock.

As the several exposures of the various rocks in the Elgin district are often miles distant from one another, and the inclination of the beds considerable, views of the most diverse character have been maintained by different geologists as to the relations of the different rocks underlying the drifts in this district, even when they agree in regard to the primary question of their age. In illustration of this it is only necessary to point to the sections of Sir R. I. Murchison and Professor Harkness taken along the same line of country.

The rocks which in the Elgin district are developed in the immediate neighbourhood of the disputed formation are proved by the most unquestionable evidence to belong to the Old-Red-Sandstone system; and from the general positions, relations, and dips of the several patches of rock exposed, we should be led to conclude that the strata in question belonged, if the country were not a greatly faulted one, to that system.

In support of this view it has been pointed out that in the higher division of the Old Red Sandstone there exist light-coloured arenaceous strata, not very dissimilar in character to the Reptiliferous Sandstone; while the Cherty Rock of Stotfield has been thought comparable to some of those concretionary limestones or cornstones which are not unfrequently found in the Old Red.

On the other hand it is a remarkable fact that, while in almost every quarry opened in these higher beds of the Old Red Sandstone remains, more or less numerous, have been found of the characteristic fishes of that system, the Reptiliferous Sandstone, which has