A large number of proteid substances, when in solution, are coagulable by heat. As the temperature of such a fluid is raised, faint opalescence at first appears, and then, at a higher temperature, masses (flocculi) of albumen separate out, in most cases, suddenly, from the fluid. It is generally held that each coagulable albumen is so affected at a definite temperature peculiar to itself; thus, egg albumen is said to become opalescent at 60° C, and to separate out in flocculi at 63° C. Unfortunately, hardly two observers agree as to the exact temperature at which opalescence and coagulation occur; thus, keeping to the example, egg albumen, Wurtz puts the coagulation point at 73° C, and Henrijean at 60° to 61° C.

The interval which elapses between tapping a muscle or tendon and the resulting movement of the limb has been estimated by many observers—Burckhardt, Tschirjieu, Waller, Brissaud and Francois Franck, Eulenberg, De Watteville, &c.—but the precise signification of these so-called reflexes is not yet fully understood. What follows is intended to add to our knowledge of this subject.

With Grunert it is necessary to take a long step backward. Although the memoirs of Bezout, Vandermonde, and Laplace were known to him, in addition to those of Hindenburg, Rothe, and Scherk, he advances only a short distance into the subject; his aim, indeed, is little more than the establishment of Cramer's rule for the solution of a set of simultaneous linear equations.His mode of presenting the subject, however, is fresh and interesting, the method of “undetermined multipliers” being taken to start with.

The present paper is a continuation of my monographs already published by the Royal Microscopical Society, London, in their Journals for June and December 1888. It has been carried out under similar conditions in the Botanical Department of the British Museum (Natural History), South Kensington, but I am especially indebted to Edmund Grove, Esq., F.R.M.S., for much valuable cooperation, and to Julien Deby, Esq., for the readiness with which he has placed at my command the resources alike of his library and cabinet. Herr E. Weissflog and Dr James Rae, R.N., have also furnished me with many excellent preparations.

§ 1. The scientific world is practically unanimous in believing that all tangible or palpable matter, molar matter as we may call it, consists of groups of mutually interacting atoms or molecules. This molecular constitution of matter is essentially a deviation from homogeneousness of substance, and apparent homogeneousness of molar matter can only be homogeneousness in the aggregate.

In the fresh-water mussel the general results are much the same as in Mytilus. Movement of the animal is as a whole right-handed and slightly forward, though this is not invariably the case.

The movement appears to be brought about by the contraction and expansion of the foot, which is wedge-shaped, and larger in proportion than in the sea-mussel. When portions are detached, however, the same four parts, or pieces of them, exhibit decided movement as in the sea-mussel. The palps rotate, the gills and mantle-lobes also move, but remarkably slowly, while the ventral margin of the foot is pre-eminently active; it is par excellence the highly motile detached portion. Where not otherwise stated, the palps, gills, and mantle-lobes are always laid out with their inner surface uppermost, and for convenience of diagrammatic representation, as well as for clearness of explanation, the palps are always supposed to start from the half-round of the clock face. Thus right-handed rotation will have the successive positions of quarter to, hour, quarter past, ending with original position at half past.

Strophanthus extract and Strophanthin are substances of great pharmacological activity, as, by subcutaneous administration, Strophanthin produces death in average-sized frogs with a dose of . of a grain, and in rabbits weighing about 3 lbs. with a dose of of a grain. The kind of action is the same with both substances, and therefore Strophanthin may properly be regarded as the active principle of Strophanthus hispidus.

It is next pointed out that the transformation of the primitive permutation into any other may be accomplished by interchanges only, because by this means any given letter may be made to occupy the first place, then any other given letter to occupy the second place, and so on. From this also it follows that any system of circular substitutions may be replaced by a system of interchanges. Should the transformation of one permutation into another be effected by interchanges, the number of these will be even or odd according as the two permutations belong to the same or different classes; for, by the above theorem, every interchange makes only one group more or one group less, and consequently the total number of interchanges, and the net increase or diminution of the number of groups, must be both even or both odd. The counting of interchanges may thus be substituted for the counting of cycles.

In the case of two Vectors, α β, the Scalars α2, β2, Sαβ are connected by no relation. In other words, the Tensors of two straight lines, and the angle between them, are three independent quantities. In this case every other Scalar Function of α and β can be expressed in terms of α2, β2, Sαβ.

In these papers the meteorological observations taken during the voyage of the “Challenger ” are discussed; and, from data collected from all parts of the world, fifty-two maps have been prepared, showing for each month of the year the distribution of temperature and pressure over the globe and the prevailing winds. Part I. deals with the diurnal, and Part II. with the seasonal phenomena of meteorology.

Although numerous most admirable descriptions of the stomach of various species of Delphinidae (the family of toothed Whales to which the Narwhal belongs) have from time to time appeared from the pens of most able observers (of whom a list will be found in the references appended), we have found it impossible to find anything more than a mere indication of the histological structure of the various portions of the walls of the peculiar digestive apparatus of these animals. As one of us had an opportunity of obtaining material in a comparatively fresh condition, we decided to make arrangements for preserving it properly, so that it might be subjected to microscopic examination on being brought to this country, With all the care that was taken some portions of the mucous membrane have suffered slightly, but in all cases the changes are so slight that we are enabled to speak positively on the points to which reference is made.