It is found almost everywhere in hot climates, and even in most temperate climates during the summer. From statistics we find that as a broad general rule in malarious countries about one-third of the total population suffers from attacks every year, and also that about one-third of the admissions to hospital and attendances at dispensaries are due to malaria. But these figures are merely based upon records, and do not cover the enormous additional number of patients who remain untreated. Thus we know that the malaria-parasites or malarial enlargement of the spleen can be found in native children in malarious countries to an enormous extent, reaching 100 per cent. in very insalubrious spots. The case mortality is only about 0.5 per cent., but the prevalence of the disease is so extremely great that the total mortality caused by it makes an addition to the general mortality of anything up to 10 per mille, or even 15 per mille; and the malady complicates all other diseases in the tropics in a way which renders them more difficult to treat. In India alone it has been officially estimated that the total deaths from malaria average about 1,300,000 a year in ordinary years, and may reach a much higher figure during years of epidemic prevalence. Thus the total bill of annual mortality and sickness which King Malaria presents to the human race is something enormous. Hence the development of the human race, especially in warm countries, has long demanded that we should ascertain exactly how this piague is propagated and should endeavour to find how best it may be prevented. It is remarkable that even more than five hundred years before Christ the ancients certainly were acquainted with one great law, namely, that malaria is connected with stagnant water, such as marshes; and there are good grounds for believing that Empedokles of Sicily actually delivered Selinus from malaria by draining its marshes or by turning two rivers into them. This knowledge seems to have been generally held since ancient times, though it must have been acquired quite empirically; but Varro and Columella, at about the time of the Christian era, actually suggested that the disease is in some way connected with insects which breed in marshes. In more modern times, however, malaria has been ascribed to noxious vapours given off by stagnant collections of waterthe hypothesis evidently being that the poison is some kind of chemical one. I have mentioned that in 1880 Laveran discovered that the disease is due to certain protozoal parasites in the blood. When this fact was accepted ten years later, many observers at once rushed to the conclusion that these parasites have an extra corporeal existence in marsh water, and actually attempted to demonstrate this by producing infection in healthy persons by such water brought from malarious localities. The experiments of Agenore Zeri (1890) are to be particularly mentioned. He gave water from the Pontine marshes persistently to number of persons orally or in spray, or by clyster but entirely without result. At the same time many thought that the poison may lie, not only in stagnant water, but generally in the soil of warm countriesthis being called the hypothesis of the telluric miasma; but, of course, this was merely a hypothesis which did not rest upon any observations or experiments. Even ten years after Laveran's discovery we were still completely ignorant as to how the malaria parasites enter the body. We might search for them in marshes and soil; but the search was likely to prove extremely difficult, because all water and soil is full of innumerable different organisms, and it would have been no light task to ascertain which of all these are really responsible for the disease among men, especially since Zeri had shown how difficult it was to produce infection by means of water in bulk. a At the same time, however, the hypothesis originally but vaguely mooted by Varro and Columella had been gaining ground. Indeed, Lancisi had repeated the same speculation in 1717, and seems actually to have suspected mosquitoes and to have studied them. So late as 1881 several theorists repeated this conception, though on studying their statements I think that little value is to be attached to them. In 1883, however, Dr. A. F. A. King wrote a most able paper on the subject, in which he gives no fewer than nineteen reasons why mosquitoes are likely to carry malaria. He thought that the insects bring the poison from the marsh and inoculate it into men. Many of his reasons are good, but others are now seen to have been untenable-and, in any case, he gave no experimental evidence. Next year, Laveran himself and Robert Koch independently enunciated the same speculation, but gave few reasons and no experiments in support of it. Ten years later, however, Manson repeated the hypothesis, but in a different form. He depended less upon the epidemiological evidence cited by King than upon certain parasitological evidence which occurred to himself. By this time (1894) the parasites of malaria had been very carefully studied, and were shown to possess, not only certain forms which provide for their propagation in the human host, but also other forms which, when the blood is freshly drawn, emit several so-called flagellated bodies. These latter forms had really led Laveran to his discovery, but their zoological significance still remained quite unexplained, and while some writers thought that they had some special significance, others believed them to be merely the result of death in vitro. Manson now urged that the flagellated bodies given off from these forms are really flagellated spores; that when mosquitoes ingest blood containing these forms, the flagellated spores escape in the insect and enter its tissues, where they ripen into some further unknown stage. Then, he thought, the insect dies two or three days later on the surface of the water, and this later stage of the parasites enters the water, and finally rises in the marsh mist to infect man. Obviously therefore Manson's hypothesis was quite different from King's; the former thought that mosquitoes derived the parasite from men and transferred it to the marsh, while King though just the opposite. Neither really reached the wonderful truth: both were half right, both half wrong. One cited parasitological and the other epidemiological evidence; and neither attempted experimental verifications. Nevertheless, all these hypotheses, including those of the telluric miasma, were necessary for the laborious experimental inquiry which was now evidently demanded in the supreme interests of human life and health. I gather from what I have been told that my own work on the subject may prove sufficiently interesting to students to be worthy of mention here, I was first drawn to the malaria problem in the year 1889, when I observed during active service in Burma that the prevalence of malaria did not at all accord with the theory of the telluric and marsh miasma; and my doubts were strengthened during subsequent years by careful thought and study. If the poison is given off in an aerial form either from water or from soil, the disease ought to be almost uniformly distributed. Such, however, is not the case, and it really occurs principally in very small spots or pockets, generally in close proximity to stagnant water. Thus in one station where I afterwards served, my regiment was severely inflicted, while other regiments, scarcely a mile distant, remained almost entirely free. I was therefore very dissatisfied with this hypothesis, and being acutely alive to the great importance of the problem, I determined to study it carefully. In 1894 Manson acquainted me with his hypothesis, and I then NATURE remembered that Laveran had said the same thing; but I was not aware of King's paper, or of the remarkable researches on Piroplasma by Smith and Kilborne. In 1895 I attacked the work experimentally at Secunderabad in India, and determined first to adopt the mosquito speculation as a working hypothesis, and then to study other hypotheses if it failed-though I was much impressed by the former. The whole history of my work has been fully given in my Nobel Lecture, published in England by the Journal of the Royal Army Medical Corps (1905); and I need mention here only the salient points. For more than two years I caused mosquitoes of the genera Culex and Stegomyia to feed on patients containing malaria "crescents," which were the proper forms for transmission according to Manson. But my failure was complete, and indeed it was impossible to follow what he thought were flagellated spores in the insect's tissues. I then adopted another technique, which was to compare insects of the same species which had been fed on malarial blood with those which had not been so fed, and to see if I could find any particular parasites in the former after they had been kept alive for some days. Many hundreds of insects were studied completely in this manner, and more than a thousand incompletely; but my failure was still complete. I obtained, however, a close practical experience of the insect's tissues, and learnt much about some common parasites which they possess. I also endeavoured to infect healthy persons by means of water in which presumably infected mosquitoes had been allowed to die, as Manson thought that such water would infect; and, lastly, I worked at a hypothesis of mine, that infected mosquitoes might carry infection by their bites, and Mr. Appia, assistant-surgeon of my hospital at Bangalore, kindly submitted to be bitten by many such insects in 1896. The result still remained quite negative. We now know the reason: the species of insect with which I was working were the wrong species. In 1907, however, I observed another variety, which I called dappled-winged mosquitoes, and which everyone now knows were Anophelines. I first saw these in an intensely malarious quarter near Ootacamund, where I myself acquired malaria during my investigations. A few months later I obtained eight of these insects in Secunderabad, and employed them for my usual experiments. Six of them died or gave bad dissections. as a was SO fortunate On August 20, 1897, I to find in the tissues insects, four days after it had been fed upon of one of these case of malaria, certain bodies which I had never observed in mosquitoes before. These contained the characteristic pigment of the malaria parasite. Next day, August 21, I found the same bodies in the last mosquito of my batch of eight-only they were now larger and more definite. To those who had not worked at the subject, such evidence might appear slight indeed; to me, after years of toil and thought, the evidence was immensely strong. A little later I found the same bodies in two more mosquitoes, and knew that I was on the right track; I felt that the two unknown quantities of this complex equation had been simultaneously found-the species of mosquito which carries malaria, and the position which the parasites take in its tissues, namely, the wall of the intestine. Now, after seventeen years, I may perhaps be allowed to mention this point in order to encourage those students who, as I was then, are toiling after the unknown. But I at least obtained success, not only by labour but also by supreme good fortune; and I believe that but for this good fortune on these NO. 2349, VOL. 94] [NOVEMBER 5, 1914 dates, we should still have remained ignorant of the manner in which malaria is conveyed, and might have remained ignorant of it for the next century. Unfortunately my work was now interrupted for nearly six months, just at a point when I expected to unravel the whole history of the malaria parasites in a few weeks; and it was not until March of next year that I was able to take up the thread again in Calcutta. For many reasons I was then unable to work at the human parasites, but commenced the study of the malaria parasites of birds, which are closely similar to the former. In a very short time I was able to demonstrate the presence in mosquitoes of pigmented bodies derived from the allied parasites. These bodies were found to grow regularly during one week after the insects had been fed, to reach maturity, and to produce a number of elongated spores. Now came an intensely exciting moment. spores? According to Manson's hypothesis, they What happens to these ought to liberate themselves in the water in which the insects died; but I had now shown that the insects did not die after two or three days, as he supposed, but may live for weeks. spores in all directions through the insect's tissues, I attempted to follow the into the lower intestine, and even into the egg. On July 4, 1898, however, I observed the fact that the spores enter the insect's salivary or poison glands. The full truth was now immediately disclosed, and proved to be far more wonderful than any of us had ever dreamed of. The parasites are not only taken from man by the mosquitoes, as Manson had supposed, and are not only put into man by the mosquitoes, as King had supposed, but both hypotheses are true, and the insect carries the parasites directly from man to man. Here then was merely another case of the great law of metaxeny, which, however, was now proved for the first time to hold good for protozoal parasites. The malaria, like many larger parasites, require two hosts for their life-cycle. These researches mapped out step by step every detail of the transformation, and gave us a much greater logical certainty than could be obtained by isolated infection experiments. Nevertheless, such experiments were attempted immediately, and in July and August I infected twenty-two out of twenty-eight healthy birds by the means of the bites of infected Culex-thus completing the whole story in detail. True, that was done with birds' malaria, and I had only seen the first steps of the process with regard to human malaria; but, any zoologist will know that with such closely allied species, the life-cycle of one is sure to be almost exactly similar to the life-history of the other-as proved to be the case here. My work was now interrupted again, and for nearly a whole year; and it was not until August, 1899, that I was able to show directly that the human parasites have exactly the same development. Meantime, however, Koch and Daniels had confirmed my work on birds' malaria; and certain Italian workers repeated it with regard to the human parasites, even to causing infection in healthy human beings (November, 1898), three months after my similar work with birds. A very important discovery had been meantime made quite independently by MacCallum and Opie in America (1897), who showed that the bodies which Manson had thought were flagellated spores, were really sperms. Thus the large pigmented cells which I had found in mosquitoes at the same date were really fertilised macrogametes. This gave a much more correct zoological interpretation to my phenomena; but did not otherwise disturb the history which I had ascertained. This then was the result obtained. Let me summarise it briefly. From the time of the Romans, we were aware that the malarial fevers are connected with marshes and stagnant water in warm countries. Later, when it was seen that the disease is not confined only to the proximity of marshes, the theorists conceived that there is a telluric poison which causes malaria, and is especially abundant in damp places. All this was a very general proposition; and in order to prevent the disease, it was necessary to undertake very extensive drainage. Now, however, the new knowledge obtained enabled us to particularise the exact route of infection. We believe no longer that the poison is spread uniformly in the air of warm countries, but know that it is always contained in the minute bodies of certain insects, and, more than that, in the still more minute salivary glands of those creatures. Here then, science had given us knowledge which could not fail to be of immense practical importance to the world. The discovery of the full life-cycle of the parasites enables us, not only to exercise the route of infection, but to determine exactly which species of mosquitoes are concerned. My failures with numerous undetermined species of the genera Culex and Stegomyia had shown that these are probably innocuous as regards malaria; and my ultimate success with certain Anophelines had shown that these were inculpated, Since then, the work of many observers has proved that, out of about five hundred Culicidæ only about twenty species carry malaria, and that all these belong to the Anophelines. So that for the prevention of malaria we are not obliged to deal with mosquitoes in general, but only with particular species. Still further, the knowledge so obtained enabled us to study exactly the habits of the culpable species. In fact, I necessarily began such studies during the whole of my researches. The genera Culex and Stegomyia breed most commonly in artificial collections of water round houses; but I saw as early as 1897 that the dappled-winged mosquitoes (Anophelines) breed principally in different sites; that is,chiefly in natural collections of water, such as marshes, puddles, streamlets, and the edges of lakes, ponds, and rivers. This had been known before in the case of certain species; but I now saw the great epidemiological and sanitary bearing of the phenomenon. The reason why malaria is connected with marshes was now fully established by quite independent work. Humanity had explained the fact by supposing that the poison of malaria itself rises from the marsh; it was now seen that it is not the poison itself that rises from the marsh but the carrier of the poison. The net result was the same, except that we now knew not only the source of the poison but the exact method of transference. After ali, humanity had reached the truth by empirical observations made during thousands of years; but science, in confirming those observations, has brought them to a fine point of exact theory. Such But these were by no means the only fruits obtained. To return to our military parallel, when a commanding position of the enemy is carried, victory extends to a large area round it. The principal function of men of science is not merely to observe, describe, and catalogue phenomena, but, above all, to solve difficult problems; and the solution of one such problem frequently gives us the solution of many more. has proved to be true also in this case; for so soon as we had solved the malaria problem we were able to apply the same theorem to a number of other diseases. As already stated, Manson had shown in 1879 that the embryos of F. bancrofti can live in certain species of Culex-but he had not shown how they pass back from these insects to man. Now, however, James and Low, working independently, showed that the embryos enter the insect's proboscis, thus suggesting that they return into the human circulation by a route similar to that which is used by the parasites of malaria, and this work has been well followed up by Bahr and many others. Another discovery, concerned with one of the most important of human diseases, namely, yellow fever, was made by Reed, Carroll, Lazear, and Agramonte during the last days of last century. Without knowing the causative agent of that disease, they yet showed by direct experiments on human beings that the infection is carried directly from man to man by another species of mosquito, Stegomyia fasciata, or calopus. It had long been stated by epidemiologists that malaria differs from yellow fever in that the former is connected with damp and decaying vegetation and the latter with insanitary conditions round houses. The former hypothesis was verified by the observation that Anophelines breed in terrestrial waters, and the latter was now explained by the fact that Stegomyia breed in artificial collections of water round houses. A little later Graham gave strong evidence in favour of the theory that dengue fever is carried by a species of Culex. Thus mosquitoes have now been incriminated as the carrying agents of no fewer than four important disease of man. But this is by no means all. I have mentioned that before my work Bruce incriminated Glossina morsitans as the carrying agent of nagana; and he and others now showed that the deadly sleeping sickness of Africa is carried by other tsetse-flies. Various Spirochetes, especially that of tick fever, have been shown to be conveyed by ticks. A peculiar type of comparatively mild fever of which the cause, like that of yellow fever, is still unknown, has been proved to be conveyed by sand-flies. Several diseases of animals have been proved to possess a similar history; and others, both of animals and men, are suspected to lie in the same category. Perhaps, however, the most important and dramatic result was that obtained in the case of plague -the most terrible of epidemic diseases, the wonder and the despair of humanity since the beginnings of history, the scourge which was so often attributed to the direct action of God. It is due really to the rat flea. And this discovery signals another advance, because plague is, as we all know, due, not to an animal, but a vegetable parasite; and we therefore see that bacteria also may adopt precise routes of entry. A similar case is that of Mediterranean fever, which is carried principally by the milk of infected goats; and leprosy (another supposed scourge of heaven) has been attributed to the bites of bed-bugs; while some are even beginning to think that measles is due to fleas. Gentlemen, I have now completed my task. We have seen at least another instance of how strongly recent advances in science bear upon medicine-how they confirm facts previously guessed at, achieve victories formerly undreamed of, and establish great theorems which will be of value to humanity so long as civilisation exists. But they affect not only the theory and the treatment of disease, but, what is perhaps still more important, its prevention; and it is especially in this line that the new theorems affect us. A whole great epidemiological group of diseases has been separated out, the so-called insect-borne diseases, and they are perhaps on the whole the most important, at least in the tropics. But, more than that, these discoveries give us practical methods of prevention, which may be summed up in the two words-no vermin. We now have a great sanitary ideal put before us: so to manage our habitations, villages, towns, and cities that the vermin in them shall be reduced to the lowest possible figure. Scores of entomologists and medical men are now dealing exactly with the habits of these creatures and showing us how to effect the required object. It demands only intelli NATURE gence, energy, and organisation on the part of administrators. Unfortunately these qualities are not always forthcoming, and administration often lags years behind the dictates of science. Although fifteen years have now elapsed since many of the facts which I have described were discovered, I think that I may say after constant study of the subject, and with all due consideration, that mankind has hitherto not effected more than about one-tenth of the improvement of health which it might have effected already if it had put its heart into the business. When I had completed my work in 1899 I had fondly dreamed that a few years would see the almost complete banishment of malaria from the principal towns and cities in the tropics; that those benign climates and those beautiful scenes would be almost rid at once of a Scourge which has blighted them from time immemorial. In this I have been disappointed. True, much has been done in certain places, as Ismailia, Italy, West Africa, and parts of India and in Panama, the Malay States, and in some other spots; but much more might have been done had we remained fully alive to our opportunities-and our duties. It is not the fault of science that we do not fully utilise the gifts which she gives to us. None of us here will live to see the full fruition of those gifts in this particular case; but we have at least seen the beginning, and may believe that our children will reap the profit. But it is ever thus with science. labourers condemned to drive tunnels through mounHer slaves are like tains-working, perhaps for years, in darkness, and oppressed by the immense spissitudes of nature above, them; but always encouraged by the hope that at any moment they may emerge into the sunlight and upon the vision of a new world. May I conclude, as appropriate to the subject of this address, with four lines which were written years ago by one who was then toiling at the researches here described and in the darkness of the most utter failure-at work, moreover, for which he had little liking or ambition. They may encourage others who are now in a like case. Writing generally of the sublime spirit of inquiry he said : Thee most we honour, thee UNIVERSITY AND EDUCATIONAL : EDINBURGH.-The election of the lord rector in each of the four Scottish Universities is one of the great events in a student's life. As a rule the candidates are chosen on account of their political eminence, and the election runs on purely party lines. For ten days preceding the election proper the Conservatives and Liberals vie with one another in the issue of posters, pamphlets, and cartoons. They raid each other's temporary offices at all hours of night and day; and in Edinburgh University when the great day of the election comes and the votes are being recorded in the various class-rooms, there is a gigantic tussle in the quadrangle so as to gain and hold a certain position of vantage below the clock. A torchlight procession finishes the day's doings. Early in the summer the two parties among the Edinburgh students chose Sir John Simon and Sir Edward Carson as their candidates, and had affairs developed normally there would have been very lively times. The shadow of the war, however, stayed the coming strife, and with great wisdom the leaders of the Liberal and Unionist Associations agreed to invite as eminent man of no political party. Their choice fell their lord rector on Lord Kitchener, himself an honorary graduate of Edinburgh University. A new lord rector is chosen NO. 2349, VOL. 94] an rence. [NOVEMBER 5, 1914 every three years. University Court, the governing body of the UniverHe represents the students on the sity, and when present presides at the meetings of the Court. This, however, is a comparatively rare occurHis one imperative duty is to address the students of the University once during his tenure of office. The addresses of Lord Kitchener and of President Poincaré, who, as announced last week, has been elected rector of the University of Glasgow, will be looked forward to with great interest. SHEFFIELD. The council of the University has made the following appointments:-Mr. Wilfrid Vickers (Manchester), to the post of junior lecturer in education and assistant-master of method; Mr. H. J. Davies, to the post of demonstrator in engineering; and Mr. F. Orme, to the post of demonstrator in non-ferrous metallurgy. The council of the University, realising that under the present exigencies of trade, manufacturers will be more than ever faced with problems requiring scientific solution, has approved the formation of a University Scientific Advisory Committee to offer assistance, under conditions arranged to safeguard the interests ing on processes within the Sheffield University area. of the consulting profession, to manufacturers carryFrom applications already received, there is doubtedly a big field for work in front of the committee. un adopted as candidate for the rectorship of the UniverMR. WINSTON CHURCHILL has been unanimously sity of Aberdeen, and will be returned unopposed on November 7. A COURSE of six lectures on chemistry, beginning on November 16, is to be given at the Royal Academy of Arts, by Prof. A. P. Laurie, professor of chemistry in the academy. The lectures will be given on Mondays, pigments and mediums used in painting the Royal Wednesdays, and Fridays, at 4 p.m. The subject of the first lecture will be the present condition and the Academy diploma pictures. Future deal with modern pigments, mediums, oils, varnishes, lectures will methods of wall painting, the theory of colour, and the chemistry of building materials. 66 THE Professional Classes War Relief Council" has issued an appeal for funds. Representatives from the chief professional institutions with representatives of the principal societies organising relief have united to form the council, so that it is acquainted with the circumstances and needs of each profession. The intention is to assist by advice and indirect help rather than by monetary assistance. The council does not intend to interfere in any way with the work of the committees controlling the various benevolent funds, but it thinks that considerable advantages will flow from bringing into close touch the professional institutions and the societies organising relief. The council will also be able to organise special kinds of assistance which will cause those funds to go further and do more ultimate good than would be possible without cooperation. The main object will be to bridge over the temporary difficulty caused by the war and to pave the way to permanent profitable employment. Since there is no other organisation or general fund to meet this kind of distress, the need for such a fund is very great. The chief forms of assistance arranged are in matters of education, training, emigration, maternity aid, and temporary employment, all of which are to be worked under separate representative subcommittees of men and women whose capabilities fit them especially for dealing with their special departments. It is necessary to form a central fund to carry on the work, this fund being used to maintain the forms of assistance proposed; to help those members of professions which have no benevolent funds; to provide assistance for the families of professional men who have given up all to enlist for the service of their country. All those who have this need at heart are invited to send donations to the treasurer, Professional Classes War Relief Council, 13 and 14, Prince's Gate, S.W. Cheques to be crossed Messrs. Coutts and Co. SOCIETIES AND ACADEMIES. LONDON. Zoological Society, October 27.-Prof. E. A. Minchin, vice-president, in the chair.-E. Heron-Allen and A. Earland Foraminifera of the Kerimba Archipelago, obtained by Dr. J. J. Simpson in the years 1907-8. The area is new so far as the Foraminifera are concerned, the only records in any way approximating to it being the species described by d'Orbigny in 1826, by Brady in 1876 and 1884, by Möbius in 1880, and by Egger in 1893, from material which was collected from adjacent areas to the east of Madagascar, and off Mauritius and the Seychelles. The material consisted of fine siftings from dredgings, and having but few molluscan fragments and stones the larger adherent forms are poorly represented, but 470 species and varieties have been identified, including two new genera, and twenty-eight new species and varieties. The general facies is strikingly similar to that characteristic of Australian, Torres Straits, and Malay gatherings. The problem of distribution thus raised is obscure, the intervening ocean being abyssal, while the species now recorded are all shallow-water types. Many of the specialised forms common to these widely separated areas do not apparently occur in similar dredgings from intervening coasts, such as the Red and Arabian Seas. No doubt the equatorial current, which traverses the Indian Ocean from E. to W. and impinges on the African coast in our area, is primarily responsible for this phenomenon.-T. H. Withers: A new Cirripede. The description was based on a number of disconnected valves from the Chalk of Surrey and a complete specimen from the Chalk of Hertfordshire. Except for three valves referred to a new species of Scalpellum (sensu lato), the whole of the material belongs to a remarkable new asymmetrical Cirripede which differs from Verruca in the more primitive structure of the valves, in the presence of two lower lateral valves on the rostro-carinal side, and in the absence of interlocking ribs. This species represents the ancestral type from which has arisen the recent group of asymmetrical sessile Cirripedes forming the family Verrucidæ, and in its structure clearly shows its origin from the symmetrical pedunculate Cirripedes of the family Pollicipedidæ. It presents further evidence that the sessile condition was arrived at independently on several different lines of descent during the evolution of the Cirripedia.-W. L. Distant: Report on the Rhynchota collected by the Wollaston Expedition in Dutch New Guinea. Challenger Society, October 28.-Dr. S. F. Harmer in the chair.-Dr. E. J. Allen: The artificial culture of marine plankton diatoms. Experiments were described in which it was attempted to grow cultures of the diatom Thalassiosira gravida in a medium containing only pure chemical salts dissolved in doubly distilled water, the medium having a composition as nearly as possible that of natural sea-water, with the addition of Miquel's nutrient solutions. In such purely artificial solutions little growth took place, but if a small percentage, even less than 1 per cent., of natural sea-water were added, large and vigorous cultures were obtained. There are reasons for sup posing that this is due to the presence in the natural sea-water of minute traces of an organic substance which acts as a growth-stimulant. Provided that the small percentage of natural sea-water be present, the amounts of the various salts constituting the artificial sea-water, as well as the total salinity of the mixture, can be varied within wide limits without much detriment to the cultures. MANCHESTER. Literary and Philosophical Society, October 6.—Mr. Francis Nicholson, president, in the chair.-R. L. Taylor and Prof. Haldane Gee: Some original pen-andink diagrams used by Dalton. The uncertainty in Dalton's mind as to the number of atoms present in water, ammonia, carbon dioxide, and other compounds is faithfully reflected in some of the diagrams, and his attempts to depict the constitution of these and more complex bodies are full of interest. October 20.-Mr. Francis Nicholson, president, in the chair.-Prof. S. J. Hickson: Sea-pens from the Malay Archipelago.-Dr. J. Stuart Thomson: Sea-pens from the Cape of Good Hope. These Pennatulaceæ were dredged off the coast of South Africa by the Cape Government trawler Pieter Faure during the ten years 1898-1907. Numerous species of scientific interest were collected, amongst which was Cephalodiscus gilchristi, an invertebrate having affinities with vertebrates. The collection of South African sea-pens is interesting, not so much because of the discovery of new species as on account of the fact that variations in certain species have been found which link genera together. One fine phosphorescent form, Anthoptilum grandiflorum, grows four or five feet in height, and is of a brick-red colour. It occurs in abundance at certain localities, probably forming dense miniature forests on the sea floor. The marine fauna of South Africa may be described as cosmopolitan in character. PARIS. Academy of Sciences, October 19.-M. P. Appell in the chair.-Gaston Darboux: A proposition relating to linear differential equations of the second order with two independent variables.-Pierre Duhem: The hydrodynamical paradox of Dalembert.-Edouard Heckel : Male castration of the giant maize of Serbia.-Comàs Solà: Photographic observation of a comet. The comet was found by its record on a photographic plate exposed October 17. It is probably identical with the comet discovered by Lunt at the Cape of Good Hope on September 18.-Ernest Lebon: A new table of divisors. Alfred Angot: The earthquake of October 3, 1914. From the seismograph installed at the Parc Saint-Maur Observatory the epicentre was calculated to be 2600 kilometres distant, in Asia Minor. The epicentre proved to be only 150 kilometres from the calculated spot. |