The observations tabulated in the present paper were taken at Ben Nevis Observatory, chiefly during August 1885. In a note communicated to the Society at the end of last session, a description was given of some observations of air-temperatures and humidities at Granton Marine Station, and it was stated that the work was to be continued at Ben Nevis. At present we confine ourselves to the hygrometrical work : it is hoped that the results of the temperature observations will be communicated to the Society early next session.

This paper forms the first half of Part I. of a research into the minute anatomy, physiology, and development of Patella vulgata. The paper aims at giving a complete account of this form in both its physiological and morphological aspects. It treats, first of all, with the external features and rough anatomy. The epidermal system is then treated in detail. Some interesting modifications of the superficial epithelium are described. The epithelial cells are usually elongated columnar, with processes connecting them with a dense subepithelial layer of connective tissue. The attachment of the circular muscle is covered with modified epithelium, the epiblast cells not being absent in that region, as is said to occur in the case of the adductor muscles of Anodon. The modified epithelium at one spot near the base of the tentacle functions as an eye. The cells are there pigmented, and the cuticle is modified so as to form a double layer, with intervening trabeculae. The retinal epithelium springs from a nerve plexus, which is supported by a mesh-work of connective tissue fibres, with large lacunas.

In a memoir published in the Chemical News, vol. xlviii. Page 37, and the Journal of the Chemical Society, 1884, page 94, I gave some account of a peculiar excretory product found in the Sepia's “liver.”The product was found to be albumin in pseudo-crystalline aggregations when examined under the microscope. These bodies are not of a constant occurrence in this organ of the Sepia. Since the publication of the above paper, which is a year and a half ago, I have made a thorough examination of this organ in Sepia, which substaniate and extend the observations of Krukenberg, Fredericq, and Jousset de Bellesme.

In connection with the observations carried on by one of us on the salinity and temperature of estuaries, it seemed desirable to examine the condition of the water near the mouth of a river flowing directly into the sea. For this purpose it was necessary to select a stream of considerable volume and free from pollution.

A very considerable number of earthworms have been referred to the genus Lumbricus, and its immediate allies Dendrobœna, Allolobophora, &c, which have in reality no marked affinities with any of these genera. Such are, for example, Lumbricus corethrurus of Fritz Müller, which Perrier has shown to belong to a distinct generic type described by him under the name of Urochœta, and Lumbricus microchœta of Rapp, which is also the type of a new genus, widely differing from Lumbricus proper. On the other hand, a very large number of species have been referred to the latter genus, concerning which there is little or no knowledge, so that it is impossible to speak with any certainty as to their exact systematic position.

In the case of a metallic conductor the resistance may be got at once by means of Ohm's Law. But when the conductor, the resistance of which is to be determined, is an electrolyte, the electromotive force acting along the circuit is only partly employed in producing the current.

The various forms of apparatus employed for procuring samples of water from beneath the surface are either designed to take up as a sample a mixture of the water in a certain vertical range, or to secure their entire charge at one definite position. The former description of water-bottle has been used almost invariably in deepsea work; the latter is necessary only in shallow water.

My object in this paper is to call attention to a few observations which occurred to me during a recent scientific survey of part of Central Africa, regarding the larger economy of tropical nature. And I wish especially, and with much deference, to attempt to supplement a well-known theory of Mr Darwin's, by bringing forward another claimant to the honour of being, along with the earth-worm, the leading organic agricultural and geological agent in nature.

From the synthetic outline of the history of biology contained in a previous paper, the practical corollary was deduced, that it was now legitimate, if not indeed urgent, for the biologist to reverse the usual order of investigation, and instead of merely adding inductively to the categories (therein enumerated) of accumulated fact, boldly to set about interpreting these in terms of their fundamental secret, that of constructive and destructive metabolism—anabolism and katabolism.

It is a familiar fact that the heart of cold-blooded vertebrates may continue to beat for a long period–even for days–after its removal from the body, but it is not so well known that contractions may occur in the heart of the higher vertebrates for a considerable time after death. On this latter point, however, there are many observations on record. Harvey noted that rhythmical contractions continued in the heart of the pigeon for some time after death, and, further, that after it had ceased to beat, it recovered its vigour, and both auricles and ventricles pulsated on the application of a stimulus, such as the tip of the finger wetted with saliva.

The electric conductivity of metals has been observed to change very greatly at their melting point, the resistance being in many cases nearly doubled when the metal is fused. The experiments recorded in the following communication originated in an attempt to investigate more fully into this fact. The metals chosen for the first observations were tin and lead, both of which have their melting points at temperatures that can be readily obtained.

The majority of recent investigations have concluded that the thickening of the rim of the blastoderm, and the new layer which is derived from it, is brought about by a true invagination of the segmented blastoderm. On the other hand, Klein and Kupffer hold that the newly formed layer is not derived from the segmented blastoderm (archiblast), but is mainly produced from an unsegmented portion of the blastoderm (parablast), which is intermediate in position between the archiblast and the yolk.

The shells of certain molluscs which are obtainable on the seashore between tides are seen to be more or less coloured green. I have noticed a fine rich colour on the operculum of a Turbo from the Pacific Ocean, which had been killed and the shell preserved dry. The shell has a high polish, the colour is the rich green of an ivy leaf, and the pigment is contained in the shell material. When the mollusc dies, and the shell is left exposed to air, light, and water, the green becomes a brownish-yellow colour. Some specimens of spirit, which had been poured off shells and fragments of coral obtained by dredging in deep waters, were examined by me for Mr J. T. Buchanan.