OF SCOTLAND.

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ascending out of the ground,—where one of the seams beneathhas been burning for years,—like the smoke of some sub-ordinate volcano. The valley of the Girvan forms a deepand very irregular basin, composed of Silurian rocks, but occu-pied for several miles by a small though not unproductivepatch of the Coal Measures, which abuts unconformablyagainst the older deposits, and lies so low in the system as tobe overlaid by the Mountain Limestone. The explorer, inpassing downwards, should strike off to the north from thepublic road at the pleasant village of New Dailly, and riseon the hill-side, after crossing the stream and passing theCastle of Dalquharran, towards the older rocks, turning first,however, by the way, to visit the coal-workings immediatelyabove the Castle, and then, a little further on, to examine, ina chance opening among the trees, the overlying fossils of theCarboniferous Limestone. He would do well, however, ifdesirous to economise time, and make himself sure of seeingall in the district that is worthy of being seen, to secure theservices of Mr Alexander M'Callum, the ingenious fossil col-lector of Girvan, under whose guidance he will learn morein a day than he could perhaps find out for himself in aweek. Under the intelligent direction of Mr M'Callum,whose services Sir Roderick Murchison has deemed worthyof special acknowledgment in his paper, I struck up from thecoal-works and overlying limestone and shale, in which wellknown fossils, such as Productus giganteus and ProductusMartini, may be detected, and reached the steep side of arocky hill overhung by wood, in which several quarries havebeen opened, chiefly for the repair of roads. The rock, adingy, olive-tinted sandstone, which in colour and quality re-minded me of some of the Caradoc sandstones, abounds infossils,—at one place, where a deeply-shaded and rarely-trod-den road has been cut into it, chiefly corals, apparently of thespecies Favositesfibrosus. But though, from their light colour,