THE FOSSILIFEROUS DEPOSITS OF SCOTLAND.

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labourer. I am not sure that we need warmly congratulateourselves on the fact,—but certainly a fact it is,—that thegeologic section of our Society is in no danger of exhaustingits work at home for a very considerable time to come. Wehave still much to do in acquainting ourselves with the ex-tinct productions of our country in those remote pre-Adamicperiods of its history when it existed, now as a group ofPleistocene islands,—now as a land covered by the Ooliticforests, and washed by seas tenanted by the ammonite andthe nautilus,—now, ere yet its existing mountains had arisenfrom the abyss, as a series of dark plains and steaming mo-rasses, brown with the rank and dusky vegetation of the Car-boniferous period,—now as an extended sea-bottom, muddyor arenaceous, swum over by the strange ganoids of the OldRed Sandstone, and with here and there a minute island,green with, so far as it is yet known, the earliest ferns andthe oldest trees,—and now as the bottom of a sea profounderstill,—a sea without visible shore, inhabited by the minutebrachipods and unique crustaceans of the earlier Silurian ages. That history of Scotland which, omitting the humanperiod as too modem, stretches backwards from the recentshells of the old-coast line to the olenus and lingula beds ofGirvan, and which is still unwritten, save in the rocks, willgive our younger members work enough thoroughly to de-cipher and transcribe for perhaps a quarter of a century tocome.

On first setting myself, about fourteen years ago, to addto my collection a set of Silurian fossils, I had to content my-self with specimens derived chiefly from England and Ame-rica. All the organisms detected at that time in the greatSilurian deposits of Scotland, —though Sir James Hall hadfound shells in the Wrae Hill limestone nearly half a cen-tury previous, and Mr Charles Maclaren in the Silurians ofthe Pentlands at least six years previous,—would scarce have