of the geological articles which appeared in the Witness newspaper during the course of the last autumn, sent him a parcel of fossils disinterred from out the deep belt of Red Sandstone which leans to the south in that locality, against the grauwacke of the Lammermuirs. Mr. Stevenson had recently discovered them, he stated, near Preston-haugh, about two miles north of Dunse, in a fine section of alternating Sandstone and conglomerate strata that lie unconformably on the grauwacke. They consist of scales and occipital plates of the _Holoptychius_, with the remains of a bulky, but very imperfectly preserved ichthyodorulite; and the coarse, arenaceous matrices which surround them seem identical with the red gritty Sandstones of the Findhorn and the _Scat-Craig_,] Now, a few years since, I had the pleasure of introducing Professor Fleming to the Organisms of the Lower Old Red Sandstone, as they occur in the neighborhood of Cromarty; and, notwithstanding his extensive acquaintance with the upper fossils of the system, he found himself, among the lower, in an entirely new field. His knowledge of the one group served but to show him how very different it was from the other. With the organisms of the lower he minutely acquainted himself; he collected specimens from Gamrie, Caithness, and Cromarty, and studied their peculiarities; and yet, on being introduced last year to the discoveries of Mr. Webster at Balruddery, he found his acquaintance with both the upper and lower groups stand him in but the same stead that his first acquired knowledge of the upper group had stood him a few years before. He agreed with Agassiz in pronouncing the group at Balruddery essentially a new group. Add to this evidence the well weighed testimony of Mr. Murchison regarding the three formations which the Old Red Sandstone contains in England, where the entire system is found continuous, the Cornstone overlying the Tilestone, and the Quartzose conglomerate the Cornstone; take into account the fact that, there, each formation has its characteristic fossil, identical with some characteristic fossil of the corresponding formation of Scotland--that the Tilestones of the one, and the lower group of the other, have their _Dipterus_ in common--that the Cornstones of the one, and the middle group of the other, have their _Cephalaspis_ in common--that the Quartzose conglomerate of the one, and the upper group of the other, have their _Holoptychius_ in common; and then say whether the proofs of distinct succeeding formations can be more surely established. If, however, the reader still entertain a doubt, let him consult the singularly instructive section of the entire system, from the Carboniferous Limestone to the Upper Silurian, given by Mr. Murchison, in his _Silurian System_, (Part II., Plate XXXI., fig. 1,) and he will find the doubt vanish. But to return to the fossils of the Cornstone group.