* Registered in terms of the Act 5 and 6 Vict. cap. 45. All rights reserved to the Edinburgh Geological Society under the provisions of the said Act. The authors alone are responsible for the facts and opinions contained in their respective papers. CONTENTS. Professor ALLEYNE NICHOLSON on the Palæontological Significance of the Mr RALPH RICHARDSON on Phenomena of Weather Action and Glacia- tion exhibited by the Alps of Switzerland and Savoy, Mr JOHN HENDERSON on the Wardie and Granton Series of Sandstones Mr RALPH RICHARDSON on Phenomena of Glaciation exhibited by the Rocks of Corstorphine Hill, near Edinburgh, Dr DANIEL HAHN on the Phosphorescence of Minerals, Mr THOMAS SMYTH on the Occurrence of Chalk-Flint Nodules and Greenstone Boulders in the Post-Pliocene Sands (stratified) at Marion- Dr DANIEL HAHN on the Want of a systematic universal Nomenclature in Mr G. H. KINAHAN on Metamorphism and Vulcanicity, . CATALOGUE of the BRACHIOPODA of the LOTHIANS and FIFE- Mr G. J. PRIMROSE GRIEVE on Metamorphism and Vulcanicity, Mr ALEXANDER SOMERVAIL on the Glacial Phenomena of Scotland, with . Mr MILNE-HOME's Address as President of the Society, Mr RALPH RICHARDSON on a Striated Erratic recently exposed at Granton, with observations on the requisites for determining the Parent Rocks . Dr W. T. BLACK on Rolled Pebbles from the Beach at Dunbar, Mr JAMES MELVIN, Bonnington, on the Nature and Origin of the Surface or Vegetable Soil, and its Influence on Geological Phenomena, Mr ANDREW TAYLOR on Metamorphism and Vulcanicity as displayed by Mr RALPH RICHARDSON'S Obituary Notice of Dr JAMES BRYCE, 141 Excursions to Alnwick Hill, Camps Quarries, and Moorfoot Hills, Mr MILNE-HOME's Address as President of the Society, and Obituary Notice of Sir RICHARD J. GRIFFITH, Bart., Mr ALEXANDER SOMERVAIL on the Higher Summits of the Pentland Mr JAMES WILSON on the Importance of Palæontological Evidence in Mr THOMAS D. WALLACE on the Structural Geology of Strathnairn, Mr RALPH RICHARDSON'S Obituary Notice of Dr PAGE, formerly President Mr ALEXANDER SOMERVAIL on Roches Moutonnées and other Points of Geological Interest in the Valley of the Urr, Kirkcudbrightshire, Mr RALPH RICHARDSON on the Connection between Geology, Meteorology, and Agriculture, as illustrated by the leading Agricultural Districts Mr ANDREW TAYLOR on the Petrology of Arthur's Seat, . Mr W. IVISON MACADAM on the Chemical Composition of a Nodule of Mr WILLIAM M'DIARMID on the North-East Coast of Norfolk, Mr THOMAS STOCK on a Section recently exposed near Straiton, TRANSACTIONS OF THE EDINBURGH GEOLOGICAL SOCIETY. SESSIONS 1874-77. Thursday, 5th November 1874. The Society held its Forty-First Anniversary Meeting on 5th November 1874, when the following Inaugural Address was delivered by Professor H. ALLEYNE NICHOLSON, one of the VicePresidents of the Society : INAUGURAL ADDRESS. On the Paleontological Significance of the Migrations of Animals. By H. ALLEYNE NICHOLSON, M.D., D.Sc., F.R.S.E, F.G.S., Professor of Natural History in the University of St Andrews. The "Introductory Address," which is usually delivered at the commencement of the Annual Session of most learned societies, is very properly intended to be of interest to all the members of the body before which it is given. Hence such addresses usually deal with the internal affairs of the Society itself, or are concerned with the current condition of the special science which the Society may happen to cultivate. That the custom here indicated is, in a general way, a good one, I cannot doubt. I am not, however, without the precedent of high authority in departing from this custom to-night; and I intend, therefore, rather to occupy your attention this evening with a few remarks upon a subject to which, it is true, I have been led by my own special studies, but which, nevertheless, has a general interest for all those who are engaged in the elucidation of geological phenomena. The subject upon which I have chosen to address you to-night concerns the conclusions which may be drawn by the palæontologist from his study of the migrations of animals. This subject has been handled more or less fully by Sir Charles Lyell in his VOL. III.-PART I. great work on the "Principles of Geology," and has also been incidentally treated of by Darwin in the "Origin of Species;" whilst Barrande, Edward Forbes, De Verneuil, and other eminent palæontologists have drawn attention to it in various portions of their works. In following such distinguished authorities, I do not propose to occupy your attention to any extent with the for the most part well-known facts relating to the migrations of existing species of animals. I may have occasion to summarise some of these facts, but that will be all. On the contrary, I purpose to confine my remarks to the bearing of these admitted facts upon various interesting geological and biological questions. I need hardly point out to you the importance of the general subject of the migrations of animals as regards the science of geology. Upon what we believe upon this subject must ultimately depend what we understand by the term "contemporaneous" as applied to different groups of strata. That the stratified rocks of the earth's crust are, wherever we may examine them, divisible into a succession of definite groups or "formations," is admitted by every geologist. That we cannot compare the successive formations of two different and remote areas except through the organic remains which they may contain is also universally conceded. Lastly, it is a matter of general belief, that when we find two formations in widely detached portions of the earth's surface containing the same fossils, or an assemblage of similar and representative forms, then we have to deal with two "contemporaneous" formations. As I have just said, however, all geologists would not attach the same meaning to the term "contemporaneous," and their views upon this fundamental question would depend upon what they believed about the migrations of animals, and of marine animals in particular. The oldest view is one which would attach the natural signification to the term "contemporaneous," and would hold that contemporaneous deposits in different regions were really deposited at precisely the same period. The more modern view, on the other hand, would hold that the word "contemporaneous," when employed by geologists, is to be construed in a loose sense. Such deposits have not been laid down at the same actual point of time, though, speaking geologically, the interval which separates them is a small one. They are "homotaxeous' deposits and they contain similar fossils, because the animals inhabiting one area migrated extensively into the other. Hence, on this view, two formations containing similar or identical fossils, if placed geographically far apart, would be held in all cases to differ in point of age, the difference between them being the length of time which would be required for the migration of the animals of the one area to the other. It is obvious, therefore, that the establishment of this exceedingly important view " |