The Paper which I have the honour of presenting to the Society, is drawn up from letters written by Captain Hall to some of his friends in this country, after a visit made to the Cape of Good Hope, and an excursion to the Table Mountain, in July last. I have given the description, as much as possible, in his own words, and have only connected parts, which, from the nature of the communications, were necessarily disjoined from one another. One of the letters being written to myself, and containing a general view of the whole, has been my guide for arranging the rest.

As the reputed fact of Archimedes having burned the Roman ships engaged in the siege of Syracuse, by concentrating on them the solar rays, has not only been doubted but disbelieved by some of the most eminent scientific men, I shall briefly give the evidence on both sides.

The burning of the ships of Marcellus is mentioned by most of the ancient writers who refer to the machines which Archimedes employed in the defence of his native city, and their statements have been repeated by succeeding authors, without any doubts having been expressed until comparatively recent times. Our earliest authorities on the subject are Diodorus Siculus, Lucian, Galen, Dion, and Pappus.

The recently published model of evolution and biogeography and the resulting classification of the Tetraconodontinae (Van der Made 1999) were criticised by Pickford (2001) on eight points. It was claimed that Conohyus giganteus is a suine, and that this ‘radically modifies tetraconodont systematics’. However, Pickford failed to demonstrate that the type specimen is a suine, and even if it were a suine, this would affect only one of over twenty species names; not a radical change of the proposed evolutionary model.

In a new investigation of this kind it is always desirable to repeat the observations under as many conditions as possible. The variables are so many that with a limited experience it cannot be expected that the subject will be exhausted, or that the conclusions arrived at from early observations will be in all cases confirmed. As an opportunity offered in the beginning of 1890 for repeating the tests made the previous year on the amount of atmospheric dust at different places on the Continent, it seemed desirable that the old ground should be gone over again rather than that the investigation should be extended to new areas. The observations made in this country have also been confined to the same stations as in 1889; and in this paper I intend giving the results of a series of tests repeated at the same stations, at about the same dates, but under the conditions existing in 1890, as has already been given for 1889 in Part I. of this subject.

The phenomena and colours of the soap-bubble have been the subject of more frequent observation than any other facts in science. For nearly two centuries they have afforded amusement and instruction to the young, and have exercised the genius of the most distinguished philosophers. Hook and Newton ascribed the beautiful colours of the soap-bubble to the different degrees of thickness of the attenuated film, and this opinion has been implicitly adopted by every optical writer down to the present day. In the latest and best Treatise on Light, Sir John Herschel expresses the current theory more distinctly than others, when he says, “that the brilliant colours which appear on soap-bubbles consist of a regular succession of hues disposed in the same order, and determined, obviously not by any colour in the medium itself, in which they are formed, or on whose surfaces they appear, but solely by its greater or less thickness.…It is at first uniformly white, but as it grows thinner and thinner, by the subsidence of its particles, colours appear to begin at its top, where thinnest, which grow more and more vivid, and arrange themselves in beautiful horizontal zones about the highest point, as a centre.”

The common forked setæ which constitute the ventral setal bundles in the Naididæ possess, like the simple setæ of many of the earthworms, a slight swelling on the shaft, the so-called nodulus. The setæ themselves are the principal organs of locomotion, being used as levers, which obtain a hold of the substratum by means of their hooked and forked distal ends; and besides being movable in an anteroposterior direction they are capable of some degree of protrusion and retraction. The position of the nodulus on the shaft is held to regulate the distance to which the seta can be protruded; though it can be retracted so that the nodulus is below the level of the epidermis, it cannot be protruded beyond that degree which brings the nodulus level with the surface.

The title which I have given to this paper, is, perhaps, faulty, and apt to lead the imagination to expect a description of the various forms of those sea-weeds which clothe the channel of the deep;—the arrangement of the species, as depending on the soil and depth of water, the food which they yield to the various creatures that browse upon them, and the protection they afford to such as take refuge among their leaves and branches. Very different, however, is the scene which I propose to describe,—a bed of peat-moss, covered by the sea at every full tide, but indicating, by the appearances which it exhibits, that its present low level is different from its original position. In other words, it is a geological phenomenon, occurring in the Frith of Tay, similar to the one observed on the Lincolnshire coast, which, in 1796, was examined by the late Sir Joseph Banks and Dr Joseph Correa de Serra, and described by the latter in the Transactions of the Royal Society of London for 1799, p. 145, under the title, “On a Submarine Forest, on the East Coast of England.” I venture to prefix the same title to this paper, which I now offer to the consideration of the Royal Society of Edinburgh, aware of its impropriety, but urged by the wish to connect similar phenomena by the common terms employed in their description.

The present inquiry is closely connected with some of the phenomena presented in golf:—especially the fact that a ball can be “jerked” nearly as far as it can be “driven.” For this, in itself, furnishes a complete proof that the duration of the impact is exceedingly short. But it does not appear that any accurate determination of the duration can be made in this way. Measurements, even of a rude kind, are impracticable under the circumstances.

In 1887 I made a number of preliminary experiments with the view of devising a form of apparatus which should trace a permanent record of the circumstances of impact. I found that it was necessary that one of the two impinging bodies should be fixed:—at least if the apparatus were to be at once simple and manageable. This arrangement gives, of course, a result not directly comparable with the behaviour of a golf-ball. For pressure is applied to one side only, both of ball and of club; but when one of two impinging bodies is fixed it is virtually struck simultaneously on both sides.

M. De Luc, in his Idées sur la Météorologie, has made some objections to the Theory of Rain which I had the honour to lay before this Society. I shall now endeavour to answer these objections; and hope the Society will forgive me for taking up a little of their time and attention with this subject. The reputation of M. de Luc is so well established in the republic of letters, that I must not neglect remarks which have the fanction of such authority; although, in the present case, they appear to me to have come from a judge who was too much preoccupied with a different system.

The Quadrature of the Conic Sections, and the Computation of Logarithms, are problems of considerable importance, not only in the elements of Mathematics, but also in the higher branches of that science. On this account, every successful attempt to simplify their resolution, as well as any new formulæ which may be found applicable to that purpose, must always be interesting, and must in some measure contribute to the improvement of mathematical knowledge.

This study presents an appraisal of the Middle Eocene–Quaternary Dugong Supersequence of the Eucla Basin, offshore southern Australia. It combines details of the rock record with seismic-stratigraphical information, and the resulting stratigraphic framework provides constraints on the nature of the late post-breakup development of the southern Australian continental margin. It is well established that the onshore-to-mid-shelf succession comprises a predominantly aggrading-to-prograding unconformity-bounded succession of carbonate platform deposits; however, our analysis of the outer shelf–upper slope section challenges the widely held view that this shelf-margin wedge represents a distally steepened prograding carbonate ramp primarily modulated by global eustasy. Instead, our results show that the Middle Eocene–Quaternary succession is punctuated by a series of unconformities that reflect a persistent tectonic instability and differential vertical movements throughout the late post-breakup period, the genesis of which is most closely related to tectonic events. Moreover, the upper slope clinoform succession was constructed and shaped predominantly by alongslope processes, and four different contourite drift types are recognised based on their seismic-stratigraphic expression: elongate mounded drift (Quaternary); infill drift (Pliocene); plastered drift (Oligocene); and separated drift (Middle–Upper Eocene). The Quaternary drift – herein termed the ‘Eyre Terrace Drift’ – is a spectacular basin-scale deposit, over 500 m thick and traced for up to 200 km along the upper slope Eyre Terrace. Upslope-migrating sediment waves are associated with this drift. Key sedimentary attributes consistent with a contourite origin include fine-grained sediment, multi-scale gradational bed contacts and pervasive bioturbation. There is also evidence of episodic downslope mass-movement processes ranging from the large-scale Late Neogene Slide, which extends downslope for 15–20 km, to sporadic slumped beds and turbidites recovered in boreholes. The interaction of alongslope and downslope processes indicates a more dynamic sedimentary setting than previously assumed along the outer margin of the Eucla Basin.

A new locality with silicified permineralised plant megafossils is reported from the upper Turonian of Colombiers, Vienne, western France. The plant fossil assemblage consists of Geinitzia reichenbachii (Geinitz) Hollick et Jeffrey and ‘Lomatopteris' superstes Saporta. Whilst G. reichenbachii is a worldwide widespread Cretaceous conifer, ‘L.' superstes is reported in western France for the first time. The latter fossil shows bipinnately compound leaf, marginal teeth, one thick primary vein, pinnate secondary veins and faint, reticulate, narrower veins. Besides its fern-like gross morphology, these characters indicate that it most likely belongs to angiosperms and eudicots. The formation of silicified nodules bearing such fossils from the Cenomanian to the Coniacian of western France was previously attributed to the secondary silicification of limestones during Cenozoic climatic weathering episodes. However, based on both petrography and preservation evidence, we demonstrate that it was an endogenic process contemporaneous to the earliest stages of fossil diagenesis created by palaeoenvironmental and climatic conditions.

Although there are reports of permineralised woods in Mesozoic and Cenozoic strata in Mexico, there are few palaeobotanical studies based on coniferous stems. Four taxa of fossil wood from three localities in Mexico are described at the anatomical level and identified taxonomically based on detailed comparisons with woods of extant and fossil taxa. Agathoxylon gilii sp. nov. and A. jericonse sp. nov. are determined from the Todos Santos Formation (Upper Jurassic), in Chiapas; A. parrensis sp. nov. is described from the Las Encinas Formation (Palaeocene) in Coahuila; and Taxodioxylon cabullensis sp. nov. corresponds with material from the Packard Shale Formation in Sonora. Dominance of Araucariaceae and Cupressaceae in this region during the Mesozoic and early Cenozoic is further supported by leaf records, but these materials may also represent other taxa, like Cheirolepidaceae, which may have araucarioid secondary xylem. Records of Brachyphyllum and/or Pagiophyllum, which may represent araucarioid or cheirolepidaceous taxa, and different cupressaceous leaves, have been collected in rocks of the same period in nearby formations. At present, the amalgamation of isolated organs to form one plant is uncertain and, thus, there is an open challenge to reconstruct the plants and better understand these extinct communities. The new fossil taxa will add to the diversity of extinct plants and conifer communities during the Mesozoic and early Cenozoic in low-latitude North America.

The bivalve ligament provides the thrust for shell opening, acting as the resistance in a lever system against which adductor muscle effort is applied. Usually, its outer lamellar layer is subjected to tensile stress, while the inner fibrous layer is compressed, with the pivotal axis located between them. However, opisthogyrate rostrate bivalves display a concave dorsal margin, and both the umbo and the postero-dorsal angle of the shell project dorsally to the ligament, which then fails to act as pivotal axis. Three opisthogyrate rostrate genera of unrelated lineages show somewhat different solutions to this morpho-functional challenge. In Cuspidaria (Anomalodesmata), the ligament is internal, subjected only to compression and ventral to the pivotal axis, a thickened periostracum develops, forcing the dorsal margins of the valves to act as pivotal axis, and the posterior parts of the shell's dorsal margins gape dorsally. In Nuculana (Palaeotaxodonta), the inner layer of the ligament is internal, the outer layer is external but reduced, and some species develop a dorsal ridge parallel to the commissural plane, on a level with the rostrum and acting as pivotal axis. In Pterotrigonia (Palaeoheterodonta) and other rostrate trigoniides, the ligament is external opisthodetic, but is allometrically reduced. Trigoniides may also develop a dorsal ridge.

Presented for the first time is a reconstruction of the skull of Diadectes (Diadectomorpha) based on several specimens of a single species Diadectes absitus from the early Permian of central Germany. Since its first discovery at the end of the 19th century the only reconstructions of the skull of Diadectes were without specific designation, despite a rich Permo-Carboniferous fossil record. The skull of D. absitus is reconstructed in dorsal, lateral, posterior, and ventral views and includes exocranial and endocranial elements. The reconstructions of Diadectes presented here are compared with those of all other authors, and the differences are analysed and discussed. The comparisons recognised three features not recorded in other species of Diadectes: (1) anterior and posterior margins of the transverse process of the pterygoid parallel one another; (2) the angle between the posterior margin of the transverse process and the lateral margin of the quadrate ramus of the pterygoid is sharply defined; and (3) the anterior ventral margin of the transverse process of the pterygoid bears a distinct sharp ridge. These characters are discussed in the context of the skull anatomy of Diadectes and inaccuracies in previous cranial reconstructions of the genus are rectified.

The public attention, animated by scientific controversy, has of late years been much directed to Geological subjects; and the certainty of many important facts, has in consequence been ascertained beyond dispute, which were formerly unknown, or at least involved in such obscurity, that no person could have ventured to assert them, without being charged with extravagance. But though, no doubt, many branches of this science still remain to be investigated, such inquiries may now be said to have acquired a considerable degree of consistency and interest, from the substantial basis upon which they have been found to rest.

Last summer I began an investigation of the Müllerian duct of Amphibians at the suggestion of Professor Wiedersheim, to whom I am indebted for most kind advice during the progress of my work, as well as for all the material that I have made use of in the course of it.

I have been able to examine stages in the development of the duct in Rana esculenta, Triton alpestris, Salamandra atra and S. maculosa, Siredon pisciformis (Axolotl), and Desmognathus; but I have paid special attention to Salamandra atra and Axolotl, which have not yet been studied in this connection. The Urodeles are easier to work with than the Anura, owing to the comparatively early formation of the Anlage of the Müllerian duct; and I have found Axolotl to be particularly instructive, as the pronephros and segmental duct persist during the early stages of the formation of the Müllerian duct.

I propose in this paper to describe what I have observed in various stages of the development of these two forms, and to compare the results thus arrived at with the appearances described in the published works on the subject.

Notwithstanding the rapid progress of zoology in other departments, the Heteropoda still remain imperfectly known, if one may form a judgment from the scantiness of definite information respecting them to be found in systematic works. Nearly all the available space is usually occupied with an exposition of the errors and doubts of the great men who gave us the first outlines of the order, while comparatively little is done to improve the subject, or make it intelligible to the student.

The Lower Devonian Posongchong Formation (Wenshan, Yunnan Province, southwestern China) consists of a series of continental deposits with an outstanding plant megafossil diversity. More than 20 years ago, this formation was interpreted as ‘Siegenian' (∼Pragian) in age based on palynology. However, such interpretation needs further evidence because of the known differences between the dispersed spore assemblages from South China and Euramerica/northwestern Gondwana. Here, we present new dispersed spore assemblages recently recovered from the Posongchong Formation. The isolated spore diversity is highly diverse, with 18 genera and 32 species. The recognised taxa include, among others, Ambitisporites avitus, Aneurospora conica, Aneurospora posongchongensis sp. nov., Aneurospora xujiachongensis, Apiculiretusispora plicata, Archaeozonotriletes chulus, Concentricosisporites agradabilis, Dibolisporites echinaceus, Emphanisporites rotatus, Gneudnaspora divellomedia, Latosporites ovalis, Retusotriletes triangulatus, Tetrahedraletes medinensis and Verrucosporites polygonalis, with Aneurospora and Retusotriletes being the most abundant forms. The known Posongchong palynoflora (previous spore data included) suggests that the Posongchong Formation assemblages can be correlated with the Pragian interval of the polygonalis–wetteldorfensis Oppel Zone (PoW). This age determination is supported by the presence of index species of PoW, such as Verrucosporites polygonalis, Dictyotriletes subgranifer and Camarozonotriletes parvus (sensu Steemans, 1989), the latter being known only from the Pragian of Belgium and Germany. Recent advances in the study of the marine faunas in the overlying sequences also indicate a Pragian age for the Posongchong Formation. This new investigation of the Posongchong palynoflora highlights differences of abundance at species level between the Gondwanan–Laurussian floras during the Early Devonian.

Up to the present time no systematic account of the cranial characters of the people of Scotland has been published. Incidental references to, and measurements of, a limited number of Scottish skulls may indeed be found in the writings of various authors, as in Sir Daniel Wilson's Prehistoric Annals of Scotland, in Drs Davis and Thurnam's Crania Britannica, and in Professor Cleland's Memoir on Variations in the Human Skull. Measurements of five Scottish crania are recorded by Sir W. H. Flower in the Osteological Catalogue (Man) of the Museum of the Royal College of Surgeons of England, four of which were found amongst the ruins of an ancient Culdee Monastery at St Andrews, and the fifth is said to be that of a Highlander. Dr Barnard Davis, in his Thesaurus Craniorum, gives the measurements of a somewhat larger number, six of which were from Caithness, and one is stated to be a Scottish Highlander. The same skulls have been remeasured and described by Dr J. G. Garson.