§ 1. A short description of some temperature observations in the Madüsee has been published in the Scottish Geographical Magazine for December 1910, and this communication aims at giving a more complete description of the observations with a first attempt at the mathematical discussion of oscillations at the surface of separation of two liquids in a basin of varying depth and cross-section.

1. In the teaching of hydrodynamics many points of difficulty arise, both for teacher and for student. The subject abounds in subtleties even in its very elements, and the advanced student frequently finds himself in a state of doubt as to fundamental questions which crop up unexpectedly in connection with various problems. The following notes contain a discussion of a few of these fundamental matters: for example, they deal with some theorems of energy which have been found difficult by students, perhaps mainly through want of perfectly explicit statement of their scope and purpose. Finally will be demonstrated a theorem of vortex-motion, particular cases of which have been given by various writers, but which I have not seen stated elsewhere in the same generality. This will be found to lead to Lord Kelvin's well-known and far-reaching theorem of circulation, and to other theorems of the vortex-motion of a perfect fluid, some of which are already known.

The extensive series of specimens of members of the Hyolithidæ which Mrs Elizabeth Gray has collected from the Ordovician and Silurian beds of the Girvan district, and submitted to me for investigation, forms the basis of the following memoir.

Through the kindness of Dr John Horne and Professor J. W. Gregory, special facilities have been afforded me of examining the other Scotch examples in the Geological Survey Collection, Edinburgh, and the Museum of Glasgow University. My thanks are also due to Dr F. L. Kitchin for the opportunity of studying the specimens in the Jermyn Street Museum.

In a memoir “On the Craniology, Racial Affinities and Descent of the Aborigines of Tasmania,” published by the Society in October 1908, I described ten Tasmanian skulls in the Edinburgh Museums, and compared them with those of this extinct race in Paris, London, Oxford, Hobart Town and elsewhere. At that time I was under the impression that I had referred to all the crania of the aborigines, seventy-nine in number, which had been preserved in museums, and for the most part had been described. The memoir did not include a description of the rest of the skeleton.

Since the time when Agassiz and Buckland made known the former presence of glaciers in the mountain valleys of North Wales, much has been written concerning the glaciation of Snowdonia, but comparatively little attention has been given to that of Western Carnarvonshire. This part of the country stretches south-westwards as the broad promontory of Lleyn between Carnarvon Bay and Cardigan Bay. Western Carnarvonshire for the most part lay outside the paths followed by the native glaciers. None of the larger valleys of Snowdonia trend in this direction, and so the marks of recent glaciation are not so fresh and striking in this region as they are further east. Hitherto no one has attempted to give any detailed account of the Drift deposits over the whole of Lleyn, but various references to the glaciation of the region are found scattered in the literature dealing with the geology of Wales.

The fossils dealt with in this part of our memoir should have been included in the first paper of the series had it been possible to treat the plants described in the order of the complexity of their structure. Unfortunately, however, the specimens did not reach our hands until Part I. was already published; and since we were no longer able to place them in their proper position in the sequence already embarked upon, it was decided to defer their treatment until the conclusion of the memoir.

Among the specimens collected by the Scottish National Antarctic Expedition and brought back to this country was a series of the embryos of penguins of various species, collected at different stages of development by Mr R. N. Rudmose Brown and Dr J. H. Harvey Pirie. These embryos were, for the greater part, of the species Gentoo (Pygoscelis papua, Forst.), the remainder of the species Adelia (Pygoscelis adeliæ, Hombr. and Jacq.). Two Emperor penguins, which had been preserved for examination by the injection of the blood-vessels, were also brought home. Through the kindness of Dr W. S. Bruce these specimens were entrusted to one of us (D. W.) for examination and report, but as the work involved in this proved to be very extensive, Dr A. Campbell Geddes was asked to undertake a share in it, and this he agreed to do.

This report contains the results of the combined investigations.

The majority of the fossils described in this paper were collected by the late Dr Marcus Gunn on the coast of Sutherland between Brora and Helmsdale, more especially on the beach of Culgower Bay in the neighbourhood of Culgower (Maps I. and II.). It is several years since I first had an opportunity of seeing Dr Gunn's collection at his house in London: at that time pressure of other work made it impossible for me to do more than recognise the importance of the fossils as records of a Jurassic flora from a country which has afforded very little information in regard to Mesozoic Botany.

The task of examining and determining the fine series of lamellibranchs collected by Mrs R. Gray in the Girvan district, from rocks of Llandeilo, Bala, and Llandovery age, has been no light one. In the first place, the literature of the subject is very scattered, and is chiefly to be found in the various reports of the Geological Surveys of the different States of North America and Canada. The work of British palæontologists is to be found in the publications of the Geological Survey and in various periodicals, but nothing systematic has been attempted before in this country, although Sowerby described and figured, in an appendix to Murchison's Silurian System, all the known species. Under these circumstances there has been the greatest difficulty in studying original types, many of which are Swedish or North American.

The anatomy of all marine mammals presents an interesting field of observation upon their structural adaptation to a particular environment, and naturally, therefore, an extensive literature already exists in respect to these mammals, notwithstanding the many difficulties connected with their detailed examination. Their large size and the rapidity with which their tissues undergo decomposition have been serious obstacles in the way of prolonged dissection both of Cetacea and of Seals. Consequently, the examination of many parts of their anatomy has, of necessity, been more or less hurried. Accordingly, in the course of the preparations for the Scottish Antarctic Expedition, led by W. S. Bruce, LL.D., etc., arrangements were made for the preservation of mammalian specimens by the same injection methods that are now commonly used for the practical study of human anatomy, and the medical officer to the Expedition received practical instruction from myself in the application of these methods.

Probably the commonest type of foliage among the impressions of Carboniferous plants is one which simulates that of our living ferns. These palæozoic fronds were originally believed to belong to the true ferns, but recently some of them have been taken from this group and included in the Pteridospermeæ. There remain, however, a large number of fronds the true affinities of which are yet doubtful. Thus, though there are still a considerable number of species which belong to the ferns, the number of doubtful examples and of those now definitely known to be pteridospermous far exceeds the number of those attributed to the Filices. Indeed, we cannot now consider the latter group to have been dominant during the Carboniferous epoch.

Harmaline is one of two alkaloids found in the seeds of Peganum Harmala, a strong-smelling herbaceous plant belonging to the order of Rutaceæ. This plant grows to a height of from 1 to 3 feet, is much branched, and profusely covered with leaves. It is found wild in S. Europe, Asia Minor, Egypt, Arabia, N.W. India, and Siberia. It is the Πήγανον ἄγριον (wild rue) of Dioscorides, Πήγανον being the name still applied in Greece to several species of Ruta.

In 1895 Professors Dewar and Fleming made an extensive and careful series of observations connecting temperature and the thermo-electromotive force of some twenty metals compared with lead. The greatest care was taken in the preparation for, and in the conduct of, the experiments, and about thirty readings, at temperatures ranging over the 300° between the boiling point of oxygen and the boiling point of water, were recorded for each metal. A full description of the mode of experimenting, with the results for each metal, was published in the Philosophical Magazine, July 1895. In their discussion of the results a further examination of them was promised, but has not appeared. Professor Fleming, however, in a Friday Evening Discourse at the Royal Institution in 1896, indicated that the lines of thermo-electric power did not appear as straight lines although they were approximately so.

The following is the first of a series of papers which I intend to issue on South African Alcyonaria. During a lengthened residence at the Cape of Good Hope, I devoted special attention to the Alcyonaria collected on board the Government steam trawler Pieter Faure. Professor Hickson has contributed two papers on Cape Alcyonarians to the volumes Marine Investigations in South Africa; but since then a large number of forms have been dredged, and there still remain in the collection entrusted to me many unidentified and undescribed species. In this first instalment I have confined myself to the Alcyonacea. The present work has been carried on in the Zoological Institute and Museum of Natural History, Berne, and it would be difficult to overstate my indebtedness to Professor Studer, who, besides giving me much valuable advice, stimulus, and encouragement, placed the entire literature of the subject at my disposal.

Protocatechyl-tropeine is one of a series of new tropeines investigated primarily with the object of determining the difference in pharmacological action between a lactone and the corresponding hydroxy-acid. Its constitution is shown in the following formula :—

Like most other tropeines, it paralyses the vagal nerve endings in the heart. It also diminishes the irritability of voluntary muscle and its myo-neural junctions, and paralyses the respiratory centre.

Since the report on the Hydroids collected by the Scotia was completed, almost three years ago, I have had an opportunity, thanks to the kindness of Dr W. S. Bruce, of looking through the enormous mass of material brought together by him during his Antarctic voyages. The search, begun in the hope of finding a few minute species—which, since many are epizoic on other forms of marine life, might readily be overlooked on cursory examination—has resulted in the addition of no less than 25 forms to the 36 already recorded. Deducting from this total of 61 forms two varieties, it appears that the Scotia collection contains in all 59 distinct species. Few, indeed, of these have been obtained in truly Antarctic latitudes—subantarctic or temperate seas having furnished the greater number—but this result is in accordance with the findings of the majority of the recent Antarctic expeditions. Dr Billard, in summarising the results of the Belgian, Swedish, and French expeditions, states that the known Hydroid fauna of Antarctic regions comprises only 32 species. But from his list he has, I think unjustly, excluded South Georgian records. His list, moreover, published before the valuable paper by Professor Hickson and Mr Gravely on the Discovery Hydroids was issued, necessarily makes no reference to the large number of forms recorded by them from Victoria Land.

Having been struck by the evident importance of Antarctic phenomena in relation to the climatic condition of lower latitudes, I have endeavoured in the following discussion to give a complete representation of these conditions, and to trace their bearing on the climate of sub-Antarctic and temperate zones. It is only now that sufficient data are available for such a purpose. I have been singularly fortunate, not only in the opportunities which I have had for obtaining access to valuable data, but also in the possession of that “practical” knowledge which has resulted from my two years' residence in the Antarctic. In any discussion of this nature it is obviously an immense advantage to have studied in the field the conditions there obtaining. This I have been able to do also for the Arctic during two voyages undertaken for this specific purpose, thereby being enabled to appreciate the great diversity in the fundamental conditions affecting the meteorology of the two Polar regions.

Under the name Tutu, three species of Coriaria—C. ruscifolia (L.), C. thymifolia (Humb. & Bonp.), and C. angustissima (Hook.)—are usually included. Other species have been described, but they appear to be varieties only. All the forms are poisonous, and in times past this plant has proved a serious hindrance to the rearing of stock in New Zealand. Lindsay, in the course of a tour through the country during the latter part of 1861 and the earlier months of 1862, “was everywhere struck by the abundant evidences of the devastation produced among flocks and herds from their feeding on the toot plant”; and he further states that “he seemed a fortunate farmer or runholder who had not lost more than 25 per cent, of his stock from toot-poisoning; while in some instances the losses were so high as 75 per cent.”

The present paper deals with further investigations into the structure, the stratification, and the plant remains of peat deposits, carried on in various districts during 1907, 1908, and 1909.

The objects of the research, stated briefly, are to determine, as far as the state of preservation of the material permits, the history of the flora on peat-covered areas since their formation during the later stages of the glacial period. This really resolves itself into a research dealing with the changes in distribution undergone in post-glacial times by part of the British flora.

That phase of the nucleus just preceding the heterotype mitosis, and which was first called Synapsis by Moore (1895), has come to be regarded as an important and critical period in the life-cycle. It was called synapsis because of the apparent condensation and contraction of the chromatin at one side of the nuclear cavity. This discovery at first received scant support, the synaptic contraction being considered by many investigators to be nothing more than an artifact—an artificial contraction caused by imperfect fixation. In 1897, however, Moore's discovery was confirmed by Miss Sargant, who not only observed it in fixed material, but also found it in the living pollen-mother-cells of Lilium.