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As has been already shown, the Islands of the Canaries, Madeiras, and the Azores possess a marine fauna closely allied to that of the old continent, notwithstanding that the prevailing set of the currents is from America. Very few mollusca are common to both sides of the Atlantic, except such as are inhabitants of the Arctic Seas, and extend along the coasts radiating from that centre. Out of about 160 species of shells of the Canary Islands and Mediterranean, of which I sent specimens to the late Professor C. B. Adams, he informed me that he could only identify one (Columbella cribraria) with a West Indian species-he had probably overlooked Neritina viridis, and perhaps one or two others.

Saxicava arctica appears to be the most cosmopolitan of mollusks ; belonging, as its specific name imports, to the Arctic Seas, but able to accommodate itself to a variety of climate, and to all zones of depth, as far as about a hundred fathoms; it has been brought from Spitzbergen, China, Behrings Straits, California, and Australia. This, with perhaps a few others, forms an exception to a general law which appears to limit the range of species in animals of this class.

The distribution of mollusca depending partly on the nature of the sea bottom, and on other conditions difficult of appreciation, is liable to great intervals of space. Neæra costellata, inhabiting the Mediterranean, Canaries, Madeira, and Norway, has only been met with at one point (Loch Fyne) between the first and last-mentioned localities, or in about 20 degrees of latitude, and there are other species which present parallel circumstances.

Before concluding, I may be allowed to make a few remarks on the distribution of Land Mollusca, which must, it is evident, be affected by many conditions, different from those which influence the spreading of their marine relatives.

We find among snails and allied genera an astonishing variety of habit. Some affect moist situations and dense forests never penetrated by the rays of the sun, feeding voraciously upon a rank vegetation; while others prefer the most arid tracts, where their food must be scanty and deficient in succulence; some, like Bulimus decollatus, pass most of their time buried in the earth ; while others, “through winter's cold and summer's parching heat," select exposed situations, and are enabled to retain their vital powers through extreme changes of temperature. Of these our little Helix umbilicata and Helix pisana may be quoted as examples. Most species seek shelter in the crevices of rocks, and under stones.

Although many terrestrial mollusca are capable of enduring not only extremos of heat and coll, but of existing for an astonishing long period

without food, (properties which, as admirably adapting them for a sea stock upon long voyages, are extensively taken advantage of for that purpose by sailors of the south of Europe ; and I may here remark, that as an article of food, the mollusca, with very few exceptions, have been too much neglected by ourselves, and that snails are not only wholesome and nutritious, but even, where prejudices do not interfere, esteemed a delicacy, not to mention that their being in request for culinary purposes would be the means of relieving our gardens from their inroads); notwithstanding, I say, their powers of endurance, they appear to be particular in the selection of locality. The arctic climate and productions are evidently not suited to snailish and sluggish habits and tastes. Even in the colder temperate regions species are few, but increase in numbers as we proceed southward, and they are found particularly to abound in limestone formations.

It is a most remarkable fact connected with the distribution of land shells, that some species are extended over very wide districts, while others are restricted to an area of a few square miles, or even less. Great Britain does not offer for observation a single species which is not likewise an inhabitant of France or Germany, though the neighbouring countries of the continent possess some which are not to be met with in this kingdom; and while thus among the hundreds of islands of Great Britain not one produces a species peculiar to itself, in the groups of the Canaries, Madeiras, and Azores, each island presents some species supposed to be strictly local.

This fact is particularly striking in the Madeiras—where Madeira proper contains but few species, while the small island of Porto Santo supplies an astonishing number, in general specifically distinct from those of Madeira, and the rocky islets called the Desertas, with difficulty accessible by man, have each some peculiar forms and in great abundance.

These facts seem to indicate that Great Britain and Ireland, including the Hebrides, Orkney, Zetland Islands, &c., have at one time formed part of the European continent, but that the more distant islands which I have named-raised by volcanic action from the depths of the Atlantic, have been each the scene of the creation of certain species which have been confined within their narrow limits by the surrounding sea.

Opposed to this idea is the fact already alluded to, that some marine littoral species, I may particularly mention Littorina striata, are common to West Africa, the Canaries, Madeira, and the Azores, which (as it is quite impossible for littoral phytophagous animals to have travelled along the bottom of the ocean,) would lead us to infer that the African continent had at one time extended as far west as the last-named islands, in accordance with an opinion very ably supported by Professor Edward Forbes, in his report on the connexion between the distribution of the existing Fauna and Flora of the British Isles, published in the memoirs of the Geographical Survey of Great Britain. Which of these theories is correct, or whether they can both, with some modification, be reconciled to each other, I must leave for geologists to determine. The only solution which suggests itself to me is, that the shores of the African continent may have extended as far west as the islands in question, and that immediately on the subsidence of the land, when it was barely submerged, and the conditions not yet incompatible with the existence of littoral species of marine Mollusca, the volcanic action took place, elevating the lofty masses of which most of these islands are composed, and that their peculiar land mollusca are of more recent origin.

Snch an explanation would, I believe, be consistent with established geological facts, but I merely suggest it for the consideration of those who are more qualified than I can pretend to be to grapple with the vast subject of the history and conditions of our planet, in times anterior to the present distribution of land and water,

THIRD MEETING.

Royal INSTITUTION.—November 14, 1853.

JOSEPH DICKINSON, M.D., F.L.S., &c., PRESIDENT, in the Chair.

At an EXTRAORDINARY MEETING, held previous to the Ordinary Meeting, the following resolution, passed at the last Extraordinary Meeting, was read and confirmed, viz.—"That the Subscription, payable by Ordinary Members, be increased to £1 ls. Od. for the present session.”

It was moved by Mr. Joun Forshaw, and seconded by the Rev. Dr. HUME: “ That this Society appoint five members of Council, viz.The Treasurer and Secretary, Mr. J. P. G. Smith, Dr. W. Ihne, and

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Mr. John HartnUP, as representatives to deliberate with the repre. sentatives of the Polytechnic, Architectural and Archæological, and Historic Societies, on the subject of the proposed union of the Societies, and report thereon."

An Amendment was moved by Mr. C. F. Salt, and seconded by Dr. IXMAN : “ That this Society has reason to be satisfied with its present condition and future prospects, and therefore respectfully declines the application to appoint five delegates to meet others to report on a proposed union."

The Amendment having been put and negatived, the original motion was carried.

It was moved by the Rev. Dr. HUME, seconded by Dr. Inman, and carried unanimously: " That it be a recommendation to the Council to publish annually, and not at longer intervals, such account of the proceedings, and such papers, or abstracts of them, as the Council may think right, and the funds warrant."

Mr. HENRY GREENWOOD, and W. H. PEARSE, M.D., were ballotted for, and duly elected Ordinary Members.

The Rev. Dr. Hume exhibited some curious manuscripts, denominated the Ireland Manuscripts, relating to the Liverpool Election of 1670.

Mr. Towson, in the absence of Mr.HARTNUP, mentioned some interesting facts relating to the planet recently discovered by Mr. Hind. This was the ninth discovered by him since he had adopted his systematic method of examining the heavens; and the total number of planets known to exist between Mars and Jupiter is now increased to twentyseven. It is a most extraordinary fact, that the last discovered is the brightest of the small planets, and could be observed in the finder of the Liverpool telescope. It was observed by Mr. HARTNUP, on the 10th, 11th, and 12th, of the present month, and its character fully established.

Mr. T. P. MARRAT exhibited a new mineral, called Cornistanite. Its appearance under the blow-pipe was similar to that of Borax, as was also its smell. It did not melt, but was very luminous, like lime or magnesia.

Mr. HENRY Cox exhibited an earth worm, which was phosphorescent. He was requested to make further observations on the subject, and endeavour to furnish such information to the Society as would enable them to determine the origin and character of the animal.

Mr. Joseph Boult read a paper, of which the following is an abstract:

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THE MOST MARKED DEVELOPMENT OF THE ARTS

PROMOTED BY WAR. The alternations of public opinion are aptly compared to the oscillations of a pendulum; usually more or less in extremes, it seldom passes through, and never abides in, that juste milieu known to mechanics as the centre of motion. Therefore, as each subject is brought under notice, it must be seen from many positions ere that is attained from which only the correct view can be taken. Whatever be the subject, a more or less extreme opinion is formed of its merits; and, according to the bias of the observer, every fact, or apparent fact, is eagerly enlisted in support of the opinion he upholds.

In all states of society the majority will be dissatisfied with things as they are, and desirous of change, in the hope of obtaining more success in the several pursuits. Many reconcile themselves to the want of success, as far as that reconciliation may be effected, by assuming that in different circumstances they would have that scope which is now denied them. In times of peace such persons are ready to welcome war, as giving an entire change to the routine of operations; in war time they clamour for peace, from a similar motive.

It was, therefore, extremely natural, during the lengthened continuance of the late European war, that public opinion should incline to peace; an inclination which was no doubt strengthened by the heavy taxation and debt which now form part of its monumental record in this country. At the commencement of that war, and for many years of its progress, public opinion was decidedly in its favour, and prepared to uphold it at any cost; but the cost reached an almost fabulous amount, and a reaction ensued. The centre of motion was approached, and it was passed ; though, happily, not before that war was honourably concluded. Since the peace, the pacific oscillation has gradually ascended higher and higher, until the utmost extreme of literal nonintervention is almost attained. The experience of school-life is ignored, and men who, when boys, withstood the tyrant of the play-ground, and protected his feeble victim from oppression, have now outgrown such weak generosity, and wish their country to look on, a dispassionate witness of similar cowardly aggression. Meanwhile, the most extreme statements, in favour of what are called the peace doctrines, are frequently hazarded, and ad captandum addresses upon the blessings of peace published.

Amongst the most favoured and frequently reiterated opinions, are +! . intimate and mutually advantageous relations subsisting between

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