In pursuance of an idea which occurred independently to Professor Tait and myself, a careful examination has been made of the solar autographs, taken at Kew and Cranford, under the superintendence of Mr Warren De la Rue. This was done with the view of detecting, if possible, some reference to planetary configurations in the behaviour of sun-spots, and in this undertaking, much aid was derived from a remark once made by Mr Beckley of Kew, when taking pictures of the sun, to the effect that, for a considerable period of time, he did not observe any spots in the act of breaking out on the visible disc of our luminary. A few words may not be amiss regarding the nature of the scrutiny to which the solar pictures were subjected, and also the value of this as a test of planetary action. In the first place, let us bear in mind, that by the rotation of our luminary, the different portions of his surface are successively presented to each planet in turn. Now, if the bodies of our system have any appreciable influence of this kind upon the sun, it is natural to expect that this should differ for any given portion of his surface, according as this portion is presented to the influencing body, or withdrawn by rotation, so that the sun's diameter is interposed between it and the planet. We should therefore expect to find that, for a given date, the spots should all begin to break out into visibility at or about the same ecliptical longitude. Similarly with regard to their healing up; and, generally, all spots on the sun's disc at a given date should behave in the same manner as they pass a given ecliptical longitude.

Although the osteology of Antarctic seals has been very completely discussed, notably by the late Dr J. E. Gray, Sir William Turner, and Professor Robert Thomson, yet the literature regarding the subject is somewhat scattered. I have therefore considered that it might be important from the point of view, as it were, of an index to publish a complete series of photographs of a set of the skulls of seals taken by the naturalists of the Scotia during the Antarctic voyage of 1902–1904.

New sauropod dinosaur material is described from Jones Ranch, Early Cretaceous of Texas (USA). Originally described as Paluxysaurus jonesi, the material from Jones Ranch has recently been referred to Sauroposeidon proteles. Elements newly prepared from dense concretionary matrix include the sacrum, ilium and proximal portion of the tail. Reconstructions of the skull and sacrum plus pelvic girdles are presented. ‘Paluxysaurus jonesi’ (=S. proteles) is a blunt-faced sauropod that was originally regarded as closely related to Brachiosaurus. Portions of the sacrum are now exposed and show that it is nearly complete, missing only parts of the first sacral (S1). The anterior sacrals are firmly fused, however, a newly discovered opisthocoelous last sacral (S6) remains unfused. A complete sequence of proximal caudal vertebrae shows a rapid transition from anteroposteriorly short and mediolaterally broad centra anteriorly, to more elongate cylindrical centra posteriorly. All proximal caudals have slightly amphicoelous centra. Some middle anterior caudals have a shallow longitudinal groove on the ventral surface of the centrum. Specimens from Jones Ranch exhibit characters of the sacrum and tail that clearly corroborate placement of ‘P. jonesi’ (Sauroposeidon proteles) as a somphospondylan titanosauriform.

If light, emanating from a fixed source, be reflected to the eye, also fixed, from the surface of a polished cylinder, which cylinder changes its position in some definite manner, the point of reflection moves in some curve or locus whose nature may be made the subject of investigation.

In the present paper I propose to examine that case in which an indefinitely thin cylinder is restricted to pass through a fixed point. The locus of the point of reflection is then a curved surface, For the present I shall still farther restrict the polished line to the plane passing through the vertex, the source of light, and the eye ; the locus being then a plane curve.

Let then a fine polished straight line, extended indefinitely both ways, turn on the vertex O, while light emanating from the source A is reflected to the eye at B; it is required to investigate the locus of the point C at which the reflection takes place.

The reflection is only possible while the polished line passes outside of the angle AOB. When the wire lies along AO, the point of reflection is at A ; when along OB, at B; and when it is equally inclined, outwards, to OA and OB, the reflection occurs at O, wherefore the curve must pass through the three points O, A, and B.

The experiments to which I shall refer were carried out in the physical laboratory of the University during the late summer session. I was ably assisted in conducting the experiments by three students of the laboratory,—Messrs H. A. Salvesen, G. M. Connor, and D. E. Stewart. The method which was used of measuring the difference of potential required to produce a disruptive discharge of electricity under given conditions, is that described in a paper communicated to the Royal Society of Edinburgh in 1876 in the names of Mr J. A. Paton, M. A., and myself, and was suggested to me by Professor Tait as a means of attacking the experimental problems mentioned below.

The above sketch which I took of the apparatus in situ may facilitate tha description of the method. The receiver of an air-pump, having a rod capable of being moved air-tight up and down through the neck, was attached to one of the conductors of a Holtz machine in such a manner that the conductor of the machine and the rod formed one conducting system. Projecting from the bottom of the receiver was a short metallic rod, forming one conductor with the metallic parts of the air-pump, and by means of a chain with the uninsulated conductor of the Holtz machine. Brass balls and discs of various sizes were made to order, capable of being screwed on to the ends of the rods. On the table, and at a distance of about six feet from the receiver, was a stand supporting two insulated brass balls, the one fixed, the other having one degree of freedom, viz., of moving in a straight line in the plane of the table. The fixed insulated ball A was made one conductor with the insulated conductor of the Holtz and the rod of the receiver, by means of a copper wire insulated with gutta percha, having one end stuck firmly into a hole in the collar of the receiver, and having the other fitted in between the glass stem and the hollow in the ball, by which it fitted on to the stem tightly. A thin wire similarly fitted in between the ball B and its insulating stem connected the ball with the insulated half ring of a divided ring reflecting electrometer.

Gigha is a little-visited island off the western coast of Kintyre and between the latter and the island of Islay. It lies about 5¼ miles south-west of West Loch Tarbert, and a little over 1½ miles from the nearest point of Kintyre where the mainland runs out for 1½ miles in the low, sandy, raised beach of Runahaorine (figs. 1 and 10).

The island is 6 miles in length from north-east to south-west, and has a greatest breadth of 2 miles. All round it are innumerable smaller isles, all elongated in the same direction as Gigha. Of these the most important are Cara, 1 mile from north-east to south-west by ½ mile in breadth, and Gigalum, ½ mile by ⅕ mile, and Craro, which is smaller still (figs. 2 and 10). The island forming Ardminish Point, on the eastern coast of Gigha, and Eilean Garbh, at the north-eastern end, will be dealt with here as if they were part of the main island, since at low tide they are connected with it by sandy isthmuses.

In the beginning of July last, I obtained, from the Frith of Forth, a species of bream, which has not been mentioned by naturalists as inhabiting the British seas. A few days after, I procured, from the same quarter, a second specimen of the same species, each exhibiting a conspicuous dark violet-coloured spot at the base of the upper part of the pectoral fins. (See Plate VI.)

On consulting the continental works on Ichthyology, I find this bream to agree best with the description Baron Cuvier has given of the Pagellus acarne, an inhabitant of the Mediterranean; but, as no figure of the fish accompanies his description, the discrimination of the species is rendered somewhat uncertain.

In preparing solutions of various salts with a view to determine their electrical conductivity, we found it of importance to know both the amount of salt in each solution, and its density. We prepared the solutions by mixing known weights of the salt under examination with known volumes of distilled water, and then measured their densities as soon as solution was complete by weighing a glass bulb in the liquid. We employed a balance which weighed to a milligramme with a kilogramme in each pan, and to give the results as great accuracy as possible we corrected for the upward pressure of the air displaced by the weights. The weight of the bulb itself was about eighty grammes. When not in use it was kept immersed in distilled water, in order to prevent change in its weight or volume being caused by impurities adhering to it. The temperature at which the densities were taken was 10° centigrade.

Recent water-undersaturated phase equilibrium data on the subsystems of the granite-H2O system have provided important new constraints on the topology of the cotectic surfaces and hence on the compositional evolution of felsic magmas. The effect of water on phase relations can be deduced from a comparison of anhydrous and H2O-saturated data or from data obtained in the presence of a CO2-bearing fluid. However, although new experimental evidence indicates that the silica enrichment of evolving H2O-undersaturated, H2O-unbuffered melts during the co-precipitation of quartz and feldspar is as previously thought for orthoclase-rich compositions, it suggests that such a trend is considerably less for Ab-rich compositions. For water-poor trachytic melts, the newly recognised strong destabilisation of the sanidine melt component relative to the anorthite melt component with increasing water content indicates that the co-precipitation of two feldspars will result in saturation of the melt with ternary alkali feldspar at an earlier stage (i.e. higher melt anorthite content) than previously thought. This, in turn, implies that the melt differentiation path will have a greater component of anorthite depletion during the equilibrium co-precipitation of ternary feldspars and that the melt will remain in the peritectic region of the two feldspar plus liquid surface over a greater interval of crystallisation, thereby enhancing the possibility that the resoption of plagioclase during the early stages of equilibrium with alkali feldspar may go to completion. Comparison of CO2-free and CO2-bearing haplogranitic phase equilibrium data suggests that CO2 may be playing an independent part in the modification of phase equilibria and may induce a significant destabilisation of the orthoclase melt component.

The causes of the peculiarities of the solar rotation exhibited by the superficial layers of the sun's body must still be considered unknown, notwithstanding recent interesting attempts at explanation. This is no doubt partly due to the difficulties of the hydrodynamical problem placed before the mathematician in an investigation of such complexity as the movements of particles in a rotating fluid subject to energetic convection. But it must also be conceded that the observational data available for a basis of mathematical, or even speculative, research are still so scanty, that for this reason alone we may perhaps not feel surprised at the failure so far of theoretical attempts.

A few years ago the late Sir C. Wyville Thomson gave me for examination some specimens of Ascidians which had been obtained during the cruises of the “Porcupine” and “Lightning,” and last summer I received from Mr John Murray the remainder of the Ascidiæ Simplices and two species of the Ascidiæ Compositæ from the same deep-sea dredging expeditions. Some additional specimens of the “Porcupine” Ascidiæ Compositæ have been placed in my hands during the last few days (January 1, 1884). The present paper contains a detailed account of the Simple Ascidians alone; the Compound forms will be worked up along with the “Challenger” Ascidiæ Compositæ, and will be described and figured in the second part of my Report upon the Tunicata of the “Challenger” Expedition. It may, however, be useful to state here that the “Porcupine” Compound Ascidians include:—

The Reverend Dr Matthew Stewart, late Professor of Mathematics in the University of Edinburgh, was the son of the Reverend Mr Dugald Stewart, Minister of Rothsay in the Isle of Bute, and was born at that place in the year 1717. After having finished his course at the grammar-school, being intended by his father for the Church, he was sent to the University of Glasgow, and was entered there as a student in 1734. His academical studies were prosecuted with diligence and success; and he was so happy as to be particularly distinguished by the friendship of Dr Hutcheson and Dr Simson. With the latter, indeed, he soon became very intimately connected; for though it is said, that his predilection for the Mathematics did not instantly appear on his application to the study of that science, yet the particular direction of his talents was probably observed by his master before it was perceived by himself.

The remarkable and close parallelism exhibited by the suctorial disc of the fish Garra and of certain tadpoles belonging to frogs of the section Rana formosa of Rana was pointed out by the late Dr Annandale and myself in 1922. Evidence was then adduced to show that such structures have come into existence through a gradual accumulation of small changes, which probably originated in direct response to the increasing swiftness of the currents as the animals invaded higher and higher levels of torrential streams. The probable evolution and the development of the disc of Garra have been described already (Hora, 1921, pp. 639–643); whereas the peculiar structure of the disc in the tadpoles has hitherto been known only in its fully-formed condition. It seemed probable that, with the discovery of the earlier stages in the development of the disc, the line of evolution of the sucker would prove to be similar to that of the sucking disc of the fishes of the genus Garra (Hora, 1930, p. 241). The observations described hereafter confirm this view.

The mines of Joachimsthal in Bohemia, have long been celebrated for their riches. They were successfully worked at an early period, and though their produce has been exceedingly fluctuating, yet the mining district, in which they occur, continues one of the most important of that country. They seem to have been particularly lucrative and important while they belonged to the house of the Counts Schlick, and when, in the beginning of the sixteenth century, a larger kind of silver coin was introduced into Germany, it took the name of Joachimsthaler, from the place of its coinage, a name which was afterwards changed into thaler, talaro, and dollar.

These mines are not less remarkable for the variety of the species, and for the beauty of the specimens which they have produced. The ancient collections of minerals at Vienna, the Imperial cabinet, that of Von der Nüll, that of Von Morgenbesser, and others, contain magnificent suites of sulphuret of silver, of red silver, &c. chiefly crystallised. The finest specimens, however, of the red silver, and perhaps the finest that ever were known in the species, were dug up so late as 1817 and 1822. The National Museum at Prague possesses one of them, consisting of a group of crystals several inches long, without having any rock attached to it, and weighing about twelve marks, or upwards of six pounds Avoirdupois, the value of the silver of which is more than L. 16 Sterling.

Alderia modesta (class Gastropoda, order Sacoglossa) has a central nervous system of a type common in the Stiligeridae and Limapontiidae. The visceral loop is short and bears two ganglia, the abdominal and supra-intestinal.

Medio-dorsal bodies, probably neurosecretory in function, are present on the cerebral ganglia. They were also found in eight other species of Sacoglossa and latero-dorsal bodies were noted in Oxynoe viridis (Pease) and Lobiger viridis (Pease).

Dissections of sixteen species of Sacoglossa showed that the order may be arranged on the length of the visceral loop and the number of ganglia on it. The evolution of medio-dorsal bodies is discussed.

The essential character of all tabular aids to computation is, that the results of many operations are recorded in some systematic way for easy reference, and that thereby the computer is spared the toil of obtaining these results for himself.

In many cases this constitutes almost the whole advantage of the table. Thus when, instead of extracting the cube root of some number, we take it from a printed book, we are merely using another's labour. The gain to the calculating community is, that the oft-repeated extraction of the same root is avoided. We also gain by the facility of systematic calculation; the labour of computing a series of successive results being in general only a small fraction of that which would have attended the same work performed in a desultory manner.

The structures known as pedicellariæ were first described by O. F. Müller. He regarded them as parasitic organisms, and described under the generic name of Pedicellaria three species—Pedicellaria tridens, P. triphylla, and P. globifera. Lamarck, in the first edition of his “Animaux sans Vertèbres,” published in 1801, and also in the second edition, following Müller, classified the genus Pedicellaria with the Corynidæ and Hydridæ among the naked polyps. Cuvier also, in the first edition of the “Regne Animal,” took the same view of the nature of pedicellariæ. It was not until 1825 that the real nature of these organs was recognised. Delle Chiaje, in his work on invertebrate animals, asserted that pedicellariæ formed an integral portion of the Echinus, and were simply appendages of the test. The following quotation from his work shows that he thoroughly understood the true nature of these structures. He says (vol. ii. p. 324):—“Fanno elleno parte integrale degli echini e servon loro per attacarsi a corpi adiacenti ed anche a ritenere gli animaletti da cibarsi.”

The following communication is intended to be the first of a series, in which I propose to consider the results of observations made at Makerstoun, near Kelso, Roxburghshire, in the Observatory of the President of this Society. These observations, and the tabular results, will be found ultimately in the volumes of Makerstoun Observations, constituting volumes of the Society's Transactions.