Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/181

1873.] JUDD-THE SECONDARY ROCKS OF SCOTLAND. 137 of a dark material disseminated through it. Locally, as is so commonly the case with rocks coloured by oxide of iron, it exhibits patches of a pinkish tint. In these sandstones false-bedding abounds, while the true bedding is often very indistinct; the jointing, on the other hand, is usually extremely well-defined; and the combination of these characters gives the rock a peculiar and distinctive mode of weathering, as was pointed out to me by my friend Dr. Gordon.

This rock is almost wholly destitute of organic remains; but at certain points, especially in some of the extensive quarries near Cummingstown, its bedding-planes exhibit ripple-marks, sun-cracks, and tracks of various kinds, including numerous series of foot- prints of very various size and character. At Lossiemouth there is a bed, about 100 feet below the top of the sandstones, which has yielded numerous scales and bones of the reptiles Stagonolepis, Hyperodapedon, and Telerpeton, while of the last-mentioned genus a single specimen (the original one) has been found at Spynie, and some remains of the first-mentioned have occurred at Findrassie. It is a singular and noteworthy circumstance that the foot-prints and reptilian remains are never found together; and in only one instance have they been obtained from the same quarry.

This sandstone rock is very extensively quarried about Cummingstown, Hopeman, Lossiemouth, and Spynie; and most of its beds yield a very valuable freestone, of excellent colour, which can be obtained in blocks of great size. It forms, indeed, one of the principal building-stones of the north of Scotland, and, the quarries being contiguous to the sea, it is exported to considerable distances.

Unfortunately the stratigraphical relations of the formation which we have been describing are almost wholly concealed by the enormous masses of Boulder-clay and other superficial accumulations which prevail to so great an extent in this district. Dr. Gordon, writing in 1859, says —

"Two circumstances tend materially to render the examination of this part of the province of Moray difficult to the geologist. There are such vast accumulations of the Boulder-clay, of the gravels and sandbanks of the drift, and of the debris of ancient sea- margins, that few sections of the underlying strata are fully exposed; and even where they are best seen, there seems to have been so great and so extensive a denudation during the time of their deposition, that a complete or uninterrupted sequence of strata and their beds has not been detected"*.

An admirable description of these various superficial deposits has been given by Mr. John Martin, of Elgin†.

The relation of the calcareous and arenaceous members of the formation we are describing is fortunately perfectly clear; and, indeed, this point has never been disputed. At Stotfield and Inverugie the peculiar calcareous and cherty rock is seen to overlie and pass down into the Reptiliferous Sandstone; and the position of the same strata


 * Edin. New Phil. Journ. New Ser. vol. ix. (185!>) p. 15.

† Ibid. New Ser. vol. iv. (1856) p. 209.