Doctor Archibald Geikie was born in Edinburgh in 1835. He was educated at the Royal High School—the most famous of the many celebrated scholastic institutions of the “Modern Athens,” and at Edinburgh University. He became an Assistant on the Geological Survey of Scotland in 1855, and in 1867, when that branch of the Survey was made a separate establishment, he was appointed Director. A few years later—in 1871—he was elected to fill the Murchison Professorship of Geology and Mineralogy in the University of Edinburgh, when the chair for these subjects was founded by Sir Roderick Murchison and the Crown in that year. Subsequently he resigned these appointments, when at the beginning of 1881 he was appointed to succeed Sir Andrew C. Ramsay, as Director-General of the Geological Survey of the United Kingdom, and Director of the Museum of Practical Geology in Jermyn Street.

If truth is elicited by the conflict of opinion, we ought to arrive at a right conclusion as to the physical history of the English Trias. Unfortunately, however, some of the hypotheses propounded result, as it seems to me, from dwelling too much on certain minor difficulties, or limiting the view to one group of facts, while others not less important are excluded. From these objections Mr. Mellard Reade's interesting communication, printed in the GEOL. MAG. for last December, does not appear to me exempt.

In the Geological Magazine for last month (January) I proposed to establish the genus Phlyctænius for the peculiar Coccostean from the Lower Devonian beds of Campbelltown in Canada, named by Whiteaves Coccostens Acadicus. In this paper I propose describing that form more in detail, along with an allied, though at the same time very strongly marked species from the Lower Old Eed Sandstone of Herefordshire, to which on that occasion I also referred.

During the course of a systematic investigation of the drifts of Flamborough Head, I have somewhat unexpectedly come across a fragment of marine Arctic beds enclosed in Boulder-clay, similar to those which form the well-known fossiliferous deposits of Bridlington and Dimlington; and as this occurs under very different conditions from those already described, it adds materially to our knowledge of the beds, and illustrates more clearly their origin.

Under the name of “Loess” there has been confounded two kinds of deposit which are due to entirely distinct and different causes. One is the fine-grained sediment left by the muddy water of flooded rivers and streams of all sorts; the other is the powdery dust and sand carried by wind, which in dry regions often produces large accumulations of this nature.

Now that so close attention is being given to the microscopic investigation of rock structures, it is somewhat remarkable that no one should yet have questioned the validity of the views currently received regarding the exact constitution of limestone. Taking account only of those limestones whose original structure has not been obliterated by subsequent changes, the general view isthat nearly the whole mass, in the great majority of cases, is either directly, or indirectly, due to organic agencies. This view is even maintained in the cases where a microscopic examination of the rock fails to reveal more than a few traces of any structure that can be regarded as organic.

The interesting phenomenon exhibited in some glassy rocks, such as obsidians and pitchstones, known as the perlitic structure, consists of a series of rectilinear and curved cracks. It has been produced artificially in Canada Balsam, and described by Mr. Grenville A. J. Cole, F.G.S.

Hitherto, any attempts of mine to produce the curved or secondary cracks on a glass plate were unsuccessful (the only result being primary cracks and appearances of air films between the glass and balsam); until noticing their occurrence on a rough mounting plate, it became evident that a roughened glass surface was the requisite thing in order to secure perfect cohesion. It is probable, therefore, that the specimen which Mr. Cole produced occurred on a ground portion of the glass plate.