OOLITIC SYSTEM OF SCOTLAND.

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latitudes. Tlie corals of the higher latitudes are, we find,either diminutive or few. Groupes of large corals are cha-racteristic of the intertropical seas, or at least of seas of eitherhemisphere that border on the tropics. I have seen an Isas-trea of Helmsdale that measured about two feet and a halfin length by about eighteen inches in breadth, and which, asI have said, a strong man could scarce raise from the ground;and arborescent masses of Thecosmila annularis have beenfound in the Coral Hag of England, that measured from afoot and a-half to two feet in height. There occur no suchcorals now in seas which lie between the fiftieth and sixtiethdegrees of latitude, whether to the south or north of theequator. And though I would not found much on one ortwo exceptional species, I do think that, seeing we would atonce pronounce a similar group of recent corals to be theproduct of seas greatly warmer than our own, we might, Ithink, be permitted to infer,—reasoning from what we know,—that the Oolitic seas of what is now Scotland were of ahigher temperature than our Scottish seas of the present day;and that, in short, in the corals of the Scotch Oolite we haveone of many evidences that in this early period these north-ern regions enjoyed a greatly more genial climate than theydo now. I may add, however, that in the same beds, mingledwith fronds of cycas and zamia, and the stems of gigantichorsetails,—all now the productions of a warm climate, andthat seem to give evidence to the same fact as the corals,—there occur numerous fragments, and occasionally wholetrunks, of fossil pines, that apparently testify, by their an-nual rings of small size, indicative of slow growth, to a cli-mate as ungenial and severe as that of Sweden or Norway .The evidence which they yield can, however, be scarce said tobe of a conflicting character with that of the corals and thecycadites. If the Oolitic land was a lofty one, a very fewmiles might have served to separate a genial from a severe

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