organic life over the surface of the earth, at the time when each
particular system of rocks was formed. Species identical with the
remains in the Wenlock limestone occur in the corresponding class of
rocks in the Eifel, and partially in the Harz, Norway, Russia, and
Brittany. The situations of the remains in Russia are fifteen
hundred miles from the Wenlock beds; but at the distance of between
six and seven thousand from those,--namely, in the vale of
Mississippi, the same species are discovered. Uniformity in animal
life over large geographical areas argues uniformity in the
conditions of animal life; and hence arise some curious inferences.
Species, in the same low class of animals, are now much more limited;
for instance, the Red Sea gives different polypiaria, zoophytes, and
shell-fish, from the Mediterranean. It is the opinion of M.
Brogniart, that the uniformity which existed in the primeval times
can only be attributed to the temperature arising from the internal
heat, which had yet, as he supposes, been sufficiently great to
overpower the ordinary meteorological influences, and spread a
tropical clime all over the globe.



ERA OF THE OLD RED SANDSTONE--FISHES ABUNDANT.



We advance to a new chapter in this marvellous history--the era of
the Old Red Sandstone System. This term has been recently applied to
a series of strata, of enormous thickness in the whole mass, largely
developed in Herefordshire, Shropshire, Worcestershire, and South
Wales; also in the counties of Fife, Forfar, Moray, Cromarty, and