George Poulett Scrope was born in London in 1797, is the second son of J. Poulett Thomson, Esq., of Waverley Abbey, Surrey, the head of the eminent mercantile firm of Thomson, Bonar, and Co., of London and Petersburg, and was educated at Harrow and St. John's College, Cambridge. During his undergraduateship he passed the winter of 1816–17 at Naples, with a part of his family, where he was struck by the phenomena of the neighbouring volcano, then in almost permanent though moderate activity. Returning to Naples in 1819, he renewed his study of Vesuvius and the volcanic territory of the Campagna; and, in the spring of 1820, made the tour of Sicily, visiting Etna and the Lipari isles. Having by these opportunities been led to take much interest in the phenomena of volcanos—at that era much misunderstood and undervalued by the rising schools of geology, both in England and on the Continent, where the doctrines of Werner were still in the ascendant—Mr. Thomson (who, on his marriage in 1821, had assumed the surname of Scrope) passed the summer of that year in a close study of the extinct volcanos of Central France, and collected there, the materials for the volume, published by him some, years later (in 1827), “On the Geology and Extinct Volcanos of Central France”—a work which has been ever since generally accepted as the best authority as to this interesting district.

The review of my “Report on the Agriculture of Belgium,” which appeared in the last number of the GeologicalMagazine, illustrated by a reprint of the map which originally accompanied it in the “Journal of the Royal Agricultural Society” (2nd series, vol. vi., part 1), has induced me to offer some further remarks on the surface-geology of that kingdom while the subject is still fresh in the recollection of the readers of this Magazine.

The outlying mass of Lias on the borders of Shropshire and Cheshire is so thickly covered with Boulder-drift, that its line of boundary throughout almost its entire circumference is very obscure. The direct sequence from the underlying Keuper Marls is scarcely anywhere visible, and I believe no record of the occurrence of the Avicula contorta zone has hitherto been published.

The Lower Silurian rocks of Scotland, largely developed as they are in the south, and in spite of the great labour that has been bestowed upon them, are by far the least known of all the fossiliferous formations of that country. While the maps of the Government Geological Survey are coloured in all the subdivisions of the strata of the other formations included in their area, the Lower Silurians are merely indicated by a common purple tint, and not the slightest attempt at a subdivision is made. Even the single bed of Limestone they contain, below the horizon of that of the W. coast, is doubtfully referred to the Llandeilo, and the sign of interrogation is carefully placed before its title. Nicol, Harkness, J. C. Moore, and many other eminent geologists, have worked different portions of these ancient deposits since the publication of “The Silurian System,” but as yet very little progress has really been made in correlating its different parts with those of the type formation of the sister country.

A Considerable amount of difficulty has been felt by geologists in accounting for the origin of the Boulder-clay of Caithness. It is an unstratified clay, of a deep grey or slaty colour, resembling much that of the Caithness flags on which it rests.

In the spring of 1869 Mr. William Adams, F.G.S., of Cardiff, sent to me for examination several pieces of Coal-shale, bearing some minute organisms which had been recognized as Entomostraca by Mr. Charles Moore, F.G.S.

The confusion which has of late years resulted from the multiplication of names for the same geological stratum, formation, or system, sufficiently indicates the necessity for the adoption of certain rules by which our geological nomenclature may be reformed and brought into a state of something like uniformity. When this necessity is acknowledged, but little doubt can arise as to the principles on which such rules must be based; the law of priority, with certain necessary limitations and exceptions, will be made to govern the terminology of Geology, as it already does that of almost every other Natural Science.