OF SCOTLAND.

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perished by the band of man at so recent a period, after bay-ing remained safely stored up in tbe cabinet of nature for somany ages, and throughout so many awful revolutions.” Imay here add, however, that shells have since been detectedin the limestones of the Wrae Hill, both by Mr Nicol him-self, and by Mr Robert Chambers, and the discovery of SirJames fully verified. In 1842, one of the members of ourRoyal Physical Society, Mr William Rliind, published hisbrief but interesting treatise on the “ Geology of Scotland.”And in referring, in a general notice, to our Grauwacke de-posits, we find him stating, that the “ formation” to whichthey belong “ corresponds to some of the beds of the Cambriansystem, as existing in Walesand that in graptolites disco-vered in the Grauwacke slates of Innerleithen, “ the first in-dications of organized fossils appear.” He adds, that “ dis-tinct specimens of these lay before him as he wrote, whichhad been presented to him by the discoverer, Mr JamesNicol.” In 1845, Mr Nicol published his “Guide to the-Geology of Scotland,”—a work which I have ever since car-ried about with me in my geologic rambles, and which, inevery instance in which its author has described from his ownobservations, I have found correct. In this useful work wefind him again referring to the graptolites of Grierston andthe shells of Wrae Hill ; and, further, briefly intimating yetanother Grauwacke locality rich in fossils, though he was evi-dently in doubt regarding its true place in the scale. “ Ina limestone below the coal near Girvan,” he remarks, “ Silu­ rian fossils are said to occur,”—a circumstance not unfre-quent,” it is added, “in the Mountain Limestone of Scot-land.” Ho one, however, is now more thoroughly convincedthan Professor Nicol, that the Silurian organisms of Girvanare not organisms of the Carboniferous series; that, on thecontrary, they definitively determine the place and age of thedeposits in which they occur as Lower Silurian ; and further,

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