We have already shown that removal of the spleen (1) or of the thymus (2) has very little effect on the animal economy. Since the spleen and thymus together comprise the largest amount of lymphoid tissue in the body of young animals, it would appear not improbable that although removal of either of these organs causes no marked disturbance, their simultaneous extirpation might be expected to give rise to some more manifest change. Friedleben (3) states that, while in his series of experiments no dog died of removal of the thymus, and that the removal of the spleen in young dogs does not influence the course of life, the simultaneous removal of the thymus and spleen causes a marked deterioration of blood formation, and leads to death.

During the last five years the greater part of my time has been taken up by the study of the plankton in the fresh-water lakes of Denmark, and in the spring of 1904 the first part of an extensive paper upon this subject was published by me. In that paper I have compared the results arrived at by me with the results of plankton explorations in other countries, and have tried to collect together everything known at the present moment regarding the periodicity and geographical distribution of the European freshwater plankton.

The problem to divide the plane, without overlapping, into a network of regular polygons with the same length of side, has been completely worked out for the three geometries for the case in which the polygons are all of the same kind. The resulting networks are called regular

In October of this year (1904) there came into my hands a very interesting specimen of a young salmon. In round terms, the fish is 1 pound in weight and nearly 14 inches long.

In June 1904 I received an invitation from Sir John Murray to visit Scotland and spend three or four weeks in exploring the Scottish lakes, in order to make a comparison between them and the Danish lakes : he was of opinion that such a comparison of the lakes of a highland and a lowland country, which had hitherto not been attempted, would lead to some interesting results. The admirable bathymetrical and physical explorations carried on by Sir John Murray in Scotland, and more especially in Loch Ness, being far advanced, the question as to the scope of the biological observations called for consideration ; so he desired me to indicate, from the impressions derived during my visit, my views as to the most useful lines of investigation that might be taken up with reference to the biology of the Scottish lakes. I was much interested in the task imposed upon me, and at the same time gratified at the prospect of assisting in the design of the biological explorations in the lakes of a foreign country ; and as it was of the greatest significance to me to learn the nature of alpine lakes, I immediately accepted the invitation. I spent three weeks in Scotland,—the first two at, Fort Augustus, on Loch Ness, and the third in Edinburgh. From Fort Augustus I explored the lakes of the Caledonian Canal, and thus became acquainted with alpine lakes; from Edinburgh I explored a few lowland lakes, especially Loch Leven. The steamer Mermaid, belonging to the Marine Biological Station at Millport, fully equipped for deep-sea work, under the direction of Dr Gemmill, was sent into the Caledonian Canal, and many hauls were taken with the dredge and trawl, as well as with different kinds of tow-nets, in Lochs Lochy, Oich, and Ness, down to the greatest depths (500 and 750 feet).

In the summer of 1902, while working as a student in the Chemistry Department of Edinburgh University, I prepared a quantity of potassium chromoxalate (Gregory's salt) as an ordinary exercise, and this led me to attempt the preparation of a similar derivative of succinic acid, since such derivatives apparently had not been obtained.

The recognition of the importance of lateral strain in the theory of elasticity, as now taught in most engineering colleges, makes it very desirable that students should make experiments upon the lateral contraction of tension specimens and the lateral extension of compression pieces with the same facility that they now determine the values of Young's modulus and the modulus of shear.

In the Annual Report of the Smithsonian Institution for 1902 Prof. Langley has published an important note on “Good Seeing,” in which he describes some experiments undertaken with the view of improving the definition of telescopic images, so far as it depends on the conditions of the air in the vicinity of the instrument. Up to now the belief has prevailed among astronomers that in order to obtain good definitions the air inside the telescope-tubes should be kept as much as possible not only at a uniform temperature but also in a state of perfect tranquillity. Langley, however, shows that this view is not quite correct, and that maintaining constant and uniform temperature inside the tube, while preventing circulation between the air inside and outside the instrument, is not sufficient to produce satisfactory telescopic images. Particularly, this method does not diminish the troublesome boiling which in solar observations proves so often to be a source of grave inconvenience to the observer. But he shows that if the air inside and near the telescope-tube is agitated by stirring, the definition becomes at once markedly better. The improvement has in all cases been so decided that the reality of this beneficial effect of stirring cannot well be doubted.

The South Orkneys are a small group of islands situated in the Southern Ocean, in about 62° S. lat. and 45° W. long., roughly 800 miles S.E. of Cape Horn. A single landing was made from the “Scotia “on Saddle Island, a small island on the north side of the group, and another on Coronation Island, the largest and most westerly. With these two exceptions all the rock specimens were obtained on Laurie Island, the most easterly of the group.

The subject of the moon's development has been dealt with by Professor G. H. Darwin by means of a highly abstruse mathematical analysis, which the present writer cannot pretend to be able to discuss. He wishes to point out, however, that Professor Darwin's theory requires the assumption that earth and moon formed, at one time, a single highly-heated fluid mass; the theory being that the moon was thrown off by centrifugal force aided by the sun's tidal influence and synchronous vibratory motion of the fluid mass.

In this memoir the author described a Pennella found attached to the back of a Balænoptera musculus, specimens of which were given to him in 1903 by Mr Chr. Castberg. The specimens were of the same species as the Pennella balænopteræ described by Koren and Danielssen in 1857, and found infesting B. rostrata. The species is a giant Copepod, and the longest examples measured about 12½ inches.

During the last generation the idea of reducing the “setting “of cloths to mathematical accuracy has been gradually taking hold of the minds of thinking men in the various textile trades. That this end is perfectly attainable is perhaps an open question, but there can be no doubt that the investigation of such problems must lead to a more satisfactory knowledge of the factors which determine the construction of fabrics.