ALBERT

Notes: Résumé Globitermes sulphureus construit normalement un nid complexe, obéissant à un plan rigoureux, qui est décrit en détail, mais semble pouvoir se contenter d'une architecture beaucoup plus simple dans des conditions écologiques particulières (zone des rizières). Une attention particulière est donnée aux matériaux constituant le nid. Les observations et analyses permettent de conclure que ce Termite utilise trois matériaux distincts: terre du sol environnant, excréments (riches en lignine), bois ou autre matière végétale non digérée (où la cellulose est abondante). Chaque région du nid comporte une proportion définie de ces 3 éléments; les matériaux terreux, prédominant à la périphérie, diminuent rapidement d'importance en allant vers l'intérieur; les matières excrémentitielles dominent dans la zone interne de la muraille, mais sont progressivement remplacées par le bois non digéré dans les régions plus internes. Dans la cavité centrale du nid sont entassés des amas irréguliers constitués presque iniquement de débris de bois très fin solidement agglomérés; ces amas sont interprétés comme des réserves alimentaires.

Notes: Conclusions et résumé 1o Les matériaux de surface de la fourmilière sont l'objet de remainiements quasi continuels, visibles d'heure en heure. 2o Les ouvrières comblent beaucoup plus rapidement les concavités naturelles ou provoquées de la surface du dôme qu'elles n'en aplanissent les bosses. 3o Le travail n'est pas régulièrement réparti autour du dôme; il est plus intense sur un secteur plus ou moins large de la périphérie. 4o Les Fourmis recouvrent la périphérie d'une souche avant son centre (avec la restriction no 3 d'un travail plus intense sur une portion de la périphérie). 5o Elles paraissent distinguer leurs propres édifices des imitations qu'en fait l'expérimentateur, même avec les matériaux de leur propre nid.

Notes: Summary 1. The anatomy and histology of the retro-cerebral endocrine system of female larvae of the antMyrmica have been described, and changes during development assessed from both aspects. These morphological and histological changes are comparable with those described in other groups of insects. 2. These anatomical and histological changes have been related to a critical developmental stage in the larva, which can be defined by developmental markers (imaginal rudiments). 3. This stage is critical since larvae reaching it may either developomit towards pupation or become dormant, in which case development is temporarily halted. 4. It appears that in larvae reaching this stage neurosecretion may occur at one (whereupon larvae develop, via non-dormancy) or may be postponed (larvae become dormant). 5. The condition of dormancy in these larvae can be recognised by examination of developmental markers alone, without further experimentation.

Notes: Summary 1. One strain occur only inApis mellifica fasciata Latr. which dominates Lower- and Upper-Egypt. This contradicts Rotter's hypothesis (1921) in which he supposed that the Egyptian honey-bee is of different strains and that the honeybee of Upper-Egypt is more primitive than that of Lower-Egypt. 2. Apis mellifica fasciata Latr. obtained from seven different districts are quite similar in the characters investigated; a) biological characters: body weight, lenghth of the life-cycle, longevity and resistance to starvation, b) anatomical character: number of ovarioles of virgin queens, and c) morphological characters: length of the flagellum, length of the tongue, dimensions and cubital index of the fore-wing, number of hooks on the hind wing, length of the third sternum and dimensions of the first wax gland. 3. The tongue length of the workers of the Egyptian honeybee is more or less uniform in Lower- and Upper-Egypt. It does not differ also considerably in a given apiary.

Notes: Résumé Pendant l'essaimage, les imagos ailés deNeotermes tectonae sont attirés en grand nombre par les branches mortes ou les chicots des cimes des arbres de teck (Tectona grandis). Ces parties mortes, pour la plupart d'origine non pathologique, s'observent en abondance dans les plantations serrées, et elles restent attachées aux arbres longtemps, se décomposant peu à peu. Pour établir leur loge, les imagos attaquent très souvent la moelle exposée aux endroits où une partie terminale s'est détachée, ou bien ils transpercent latéralement les branches pourrissantes. Ils n'utilisent que rarement d'anciens forages abandonnés. Les colonies primaires sont saprophages. Leurs galeries initiales suivent le fil du bois et sont tantôt dirigées vers le sommet, tantôt et le plus souvent vers la base des branches, ce qui s'explique peut-être par le plus fort degré hygrométrique des parties basales. Ordinairement, les galeries des colonies juvéniles s'étendent après un ou deux ans dans les parties vivantes de la cime ou du tronc, mais les colonies peuvent subsister pendant trois ans et plus sur le bois mort, atteignant exceptionnellement dans ce milieu la phase de première apparition des individus ailés. On peut trouver jusqu'à six colonies primaires dans la même branche. Bien qu'occupant la même partie limitée d'un arbre et possédant des galeries entremêlées, les colonies peuvent rester séparées très longtemps, du moins lorsque leur nombre n'excède pas deux. Les jeunes colonies vivent côte à côte avec d'autres espèces d'insectes utilisant le bois pourri comme nourriture ou, tels que les fourmis, comme abri. Une fois établies, les colonies paraissent ne subir que peu de pertes à la suite d'influences défavorables ou de prédateurs; chose curieuse, elles ne sont pas recherchées par les pics.

Notes: Summary Information on flight periods and times of flight ofCubitermes ugandensis and ofC. testaceus in eastern Uganda is reviewed. All work was done in the laboratory with the exception of a few field observations on flight. Alates removed from the mound were negatively phototactic and gregarious. These characteristics were reversed by use of the wings. Alates would fly only if free of contact with other termites of the colony and in the presence of light. Observations were made on the flight activity ofC. ugandensis in connection with light intensity. Wing shedding in both species was stimulated by pairing or attempted pairing but, inC. ugandensis at least, was not dependent on such stimulation. Wing shedding was followed by indifference to light. Artificial wing removal demonstrated that inC. ugandensis the connection between loss of wings and loss of positive phototaxis was not a direct one. The method of wing shedding is discussed. Females of both spp. did not generally take up the calling attitude until they had paired with, and lost, a male. In the absence of males,C. ugandensis females would run actively for many minutes after wing shedding, after which the calling attitude was taken up between further periods of active running. An apparent defence mechanism against small predators, used byC. ugandensis females in the calling attitude, was noted. The presence of wings did not inhibit pairing in either species. Male tandems were frequent but nearly always very inconstant. Female tandems were not seen and no female was seen to follow a male. Tandems showed no positive geotaxis and remained indifferent to light.C. ugandensis females tended to climb up and down for some minutes after pairing. Thigmotaxis proved important in nest site selection by both species. Burrowing appeared to be dependent on external factors and not part of a behaviour pattern. Gregariousness returned with selection of the nest site but definite photonegative behaviour was not seen until the pairs were installed in cells. The plasticity of post-flight behaviour is discussed.

Notes: Summary The present study summarizes the today's knowledge of the genusMimopria Holmgr. The synonymy of the genus is discussed.Atrichopria Kieffer andKiefferopria Brèthes are considered synonyms ofMimopria Holmgr.Atrichopria rufa Kieffer is considered synonym ofMimopria ecitophila Holmgr.Kiefferopria horni Brèthes andAtrichopria seminigra Kieff. are transferred herewith inMimopria Holmgr. New key ofMimopria-species described up to now is attached.

Notes: Summary This work deals with analysis of soils from mounds belonging to the following Termites:Bellicositermes bellicosus Smeathman,Bellicositermes natalensis Haviland,Amitermes unidentatus (evuncifer) Silvestri,Nasutitermes ueleensi Sjöstedt andCubitermes fungifaber Sjöstedt. The following data were collected: texture, organic carbon and nitrogen rates, loss by calcination,pH and colour of dry soil. In order to compare the different materials, samples were always taken in the mounds and on the adjacent land. The native building materials differ with the Termite species. As for theMacrotermitinae which take soils from the depth, the texture is finer in the soils coming from the mounds than in the adjacent soils; there is no difference forAmitermes mounds; but for the mounds ofCubitermes andNasutietermes, the rate of fine elements is greater than in the surrounding soils which contain an important amount of iron oxyde concretions. The buildings ofMacrotermitinae are poorer in organic matter than the adjacent land, but the contrary occurs with the mounds ofCutitermes, Nasutitermes andAmitermes.

Notes: Résumé Le rapport entre les amplitudes et le déphasage des pulsations des champs magnétique et électrique enregistrés au niveau du sol, dont les périodes sont supérieures à la seconde, dépendent de la variation de la conductivité avec la profondeur En vue d'interpréter les résultats des observations effectuées au Centre de Physique du Globe de Dourbes, divers types de distribution de la conductivité sont étudiés, et en particulier un modèle composite constitué d'une couche de conductivité uniforme prolongée par un milieu où la variation de la conductivité est continue semble être susceptible de représenter les résultats expérimentaux.

Notes: Summary The vertical gradient of gravitational field is derived by a corollary ofGreen's theorem from the gravitational potential. For the solving of the integral defined the vertical gradient is given a simple approximation. For practical computation are presented the numerical values of coefficients.

Notes: Summary The theory of a Zöllner's horizontal pendulum with perfect wires of suspension is made. We use the Euler's angles of the axes of a system fixed in the moving body relatively to fixed axes and a fourth angle caracterising the amplitude of a motion of translation. We give the conditions for the decoupling of the four types of motion (pure rotation, pitching, rolling, translation) and the equations of forced motions. A rigorous theory of Lettau's double pendulum is initiated. We suppose that the primary pendulum has only one degree of freedom. First the case of a secondary pendulum not disturbing the primary one is examined, and then the case of an indifferent primary pendulum, wich enables us to understand what happens in the normal case. The potential energy of the secondary pendulum is not always a minimum in the central position when the plane of symmetry is vertical and it is possible that parasitesolutions appear, stabler than the central one. This study is extended to the case of a non-vertical plane of symmetry and indications are given for the study of the free motions of the system. In conclusion we could say that this system is simple only at first sight. Its use would be necessary in the case of a real great drift of the underground of the station. But in the contrary case ordinary simple pendulums are sufficient and more easy to understand.

Notes: Summary The subject is treated, how far the events of motion in the sea can be reproduced by application of methods, which are based on the hydrodynamical differential equations. In particular comparisons between observed and computed sea-levels for the tides in estuaries and in the North-sea are worked out. Furtheron, a method is communicated, which is giving the shape of the sea-surface, when distribution of density is known, without using a layer of no motion. The result shows a remarkable agreement with the topography of the sea-surface in the South-Atlantic given byA. Defant.

Notes: Zusammenfassung Der nachfolgende Aufsatz diskutiert erneut die Frage der Korrekturen bei der Auswertung seismischer Filme. Die vom Verfasser vorgeschlagene Methode ist auf alle Verfahren der angewandten Seismik anwendbar und kann zur Entlastung des Wissenschaftlers von jedem Zeichner oder Rechner gehandhabt werden.

Notes: Summary The fault plane solution for the Alaska earthquake of October 24, 1927, is obtained and is found to be similar to that of the more recent earthquake of July 10, 1958, which occurred in the same general region. Using the data from the plane of polarization of theS waves, the mechanism at the focus is seen to conform to a single couple or faulting model rather than to a double couple. TheS waves, further, select one of the nodal planes forP as the fault plane.

Notes: Summary An electronic sound spectrograph has been used to analyze the transients in complicated earthquake and explosion signals. Transient analysis with a sound spectrograph gives a means for directly obtaining group velocity at each of the spectral frequencies for each of the separate arrival branches, for any type of transient signal. Compared to frequency analysis, it presents the fine spectral structure of the signal as it changes with time, not an average over a time that includes many parts of the seismic signal. Dispersion as well as the body wave spectrum of theP wave has been observed by transient analysis of seismic signals. Dispersion has also possibly been observed in theS wave, and in the various multiply reflectedS waves, which have been found to increase in period from one arrival to the next. The dispersed pattern of arrival of fundamental and higher mode surface waves has been observed for oceanic, continental, and mixed paths. Among these signals is a clear indication of the continental second shear mode. The separation of surface waves for the direct and complementary paths has also been accomplished. Our results compare well with those obtained by standard techniques. The dispersion of the fundamental and higher mode signals from explosive sources in shallow water may be easily studied by making sound spectrograms and amplitude sections of these seismic signals. These shallow water shots show bubble pulses and Airy phases, which are clearly defined on the spectrograms and sections.

Notes: Summary The author describes the pulsing ionospheric technique which since 1939 has been successfully employed for forecasting surface weather.

Notes: Zusammenfassung Messungen der Gefrierkernkonzentration während der Jahre 1957 und 1958 zeigten im Verlauf des Monats Januar markante Spitzenwerte, die zeitlich mit den vonE.G. Bowen vorhergesagten Maxima übereinstimmten. Da es große Schwierigkeiten bereitet, das Auftreten dieser Maxima durch die «Meteorstaubhypothese» zu erklären, wird auf Umstellungen der Zirkulation der Atmosphäre im Januar hingewiesen, die möglicherweise diese Schwankungen der Gefrierkernkonzentration auslösen können.

Notes: Zusammenfassung Der Transport radioaktiver Aerosol-Partikel durch die Atmosphäre wirft neue meteorologische Probleme auf. Eine kinematische Methode der Vorhersage von Trajektorien zeigt erhebliche Unterschiede gegenüber den Stromlinien. Die Ausbreitung von Partikelwolken ist eine Funktion der Vektorstreuung des Windfeldes und einem von der Zeit abhängigen Parameter. Der Massenaustausch zwischen der Troposphäre und der viel partikelreicheren Stratosphäre vollzieht sich vorwiegend in horizontaler Richtung im Niveau der Strahlströmungen. Einige Besonderheiten der Stratosphäre über dem tropischen Pazifik werden kurz beschrieben: die Aufspaltung der Tropopause über dem Äquator und die großen zeitlichen Änderungen der zonalen Windströmungen. Während die Gravitation und das Auswaschen durch Niederschläge vorwiegend gröbere Partikel (Durchmesser〉2μ) zur Sedimentation bringen, fällt die Koagulation an Wolkenelementen hauptsächlich die kleinsten Partikel (〈0.1 μ) aus.

Notes: Summary By comparing the equalities expressing the solar flux within a wide spectral region on the assumption of an extintion within the atmospheric aerosol given by βαλ−α and that of an extintion represented by β1λ−1, a relationship is established by means of which: 1) The error is discussed which is done when the air opacity is expressed by β1, in the case when α≠1; 2) A simple and quick method is worked out for determining the parameters βα and α from actinometric observations, carried out within the spectral regions λ〈525 mμ and 525 mμ〈λ〈625 mμ.

Notes: Abstract I has been shown that irradiation of air by sun-rays leads to a formation of atmospheric condensation nuclei, as measured with the automatic nucleus counter (1). To control the influence of the material, experiments were done in a gasometer where a rubber balloon was built in, also in a metal container covered either with uviol glass or window glass, or with air in a polyethylene balloon. The same influence of sunrays was observed in each case. Similar experiments were then done with compressed air from a metal container, or with oxygen gas, nitrogen gas or nitrous oxide all from metal containers. In all cases sun-rays produced condensation nuclei; the effect was present both at 1800 m and at 270 m altitude. Diffuse sunlight with high clouds also had an effect. Infra-red radiation and mechanical shaking were without result, but ultraviolet rays from a quartz-mercury lamp increased the nucleus count of the balloon whether it contained air or one of the above-mentioned gases. As yet it has not been possible to decide the mechanism of formation of these nuclei and what their meteorological and biological role might be. The detailed paper will appear later in «Geofisica pura e applicata».

Notes: Summary In brief a newly developed freezing nuclei meter is described. Results of measurements made with this instrument in New Jersey, California and in the Thule area, Greenland, are shown. These data are compared with measurements of condensation nuclei, simultaneously made with the General Electric and the Aitkennuclei counters. Also the results obtained from some measurements of the lightscattering function of the aerosol in industrial areas near New York City are presented.

Notes: Summary Working on the hypothesis that atmospheric ice-forming nuclei are largely of terrestrial origin, the nucleating ability of various types of soil particles and mineral dusts has been investigated. Of the thirty substances tested, twenty-one, mainly silicate minerals of the clay and mica groups, were found to produce ice crystals in supercooled clouds and also on supercooled soap films at temperatures of − 18° C, or above, and of these, ten were active above − 12° C. The most abundant of these is kaolinite with a threshold temperature of − 9° C. Ten natural substances, again mainly silicates, were found to become more efficient ice nuclei having once been involved in ice-crystal formation, i.e. they could be pre-activated or «trained». Thus, ice crystals grown on kaolinite nuclei, which are initially active at −9° C, when evaporated and warmed to near 0° C in a dry atmosphere, leave behind nuclei which are thereafter effective at − 4° C. Particles of montmorillonite, another important constituent of some clays, and which are initially inactive even at −25° C, may be pre-activated to serve as ice nuclei at temperatures as high as −10° C. It is suggested that although such particles can initially form ice crystals only at cirrus levels, when the ice crystals evaporate they will leave behind some «trained» nuclei which may later seed lower clouds at temperatures only a few degrees below 0° C. On this hypothesis, the fact that efficient nuclei are occasionally more abundant at higher levels would not necessarily imply that they originate from outer space. Indeed, in view of our tests on products of stony meteorites, produced both by grinding and vaporization, which show them to be ineffective at temperatures above − 17° C, it seems likely that atmospheric ice nuclei are produced mainly at the earth's surface, the clay minerals, particularly kaolinite, being a major source. Although a good deal of work has been carried out in different laboratories on the ice-nucleating ability of a wide variety of inorganic compounds, there has been little agreement in the results. Careful tests carried out in our laboratory have revealed a number of reasons for this. Spurious results may be obtained because of the presence, in the air or the chemicals, of small traces of silver or free iodine, leading to the formation of silver iodide: if all such trace impurities are removed, many of the substances that have been claimed to provide efficient ice nuclei are found to be quite ineffective. It is dangerous to infer that all twinkling particles in a water cloud are ice crystals since particles of some seeding agents glitter even at positive temperatures. The threshold temperature of a nucleant will depend upon the criterion adopted for the onset of nucleation, i.e. upon the fraction of the total number of particles of seeding agent which are activated; this, in turn, will depend upon the fraction of particles which happen to possess suitable crystallographic faces for nucleation. Much may also depend upon the manner in which the test is performed. Since some nucleating materials produce ice crystals only after a delay of 30 seconds or more, they may appear to be ineffective if tested in the transient cloud of an expansion chamber but highly effective if allowed to remain in an ice-supersaturated atmosphere for a minute or more. Again, we have found that the efficiency of some nuclei is governed by the supersaturation as well as the temperature of the environment, and the supersaturation regimes in expansion, diffusion, and mixing-cloud chamber may be widely different. Highly soluble particles, although able to act as «sublimation» nuclei in atmospheres super-saturated relative to ice but sub-saturated relative to water, on entering a water cloud go quickly into solution and lose their nucleating ability. Inorganic substances which definitely nucleate a supercooled water cloud in a mixing-cloud chamber at temperatures of −15° C and above are: AgI (−4° C), PbI2 (−6° C), CuS (−6° C), Ag2S (−8° C), Ag2O (−9° C), HgI2 (−8° C), V2O5 (−14° C), Cu2I2 (−15° C), the figures in brackets indicating the threshold temperatures at which about one particle in 104 becomes active as an ice nucleus. Cadmium iodide (−12° C), ammonium fluoride (−9° C) and iodine (−14° C) are examples of salts which will act as sublimation nuclei in an ice-supersaturated atmosphere and will nucleate a supercooled soap film, but which are ineffective in a water cloud because of their solubility. Although the most efficient nucleating agents tend to be hexagonal in structure, there are some striking exceptions e.g. Ag2S, Ag2O, HgI2, but in most cases, we have been able to find a low-index crystal surface on which the ice lattice could grow with a misfit of only a few per cent. In an attempt to investigate the nucleation mechanism in more detail, we have studied the growth of ice on single crystals of various nucleating agents. Perfect orientation of ice crystals has so far been observed on the basal faces of silver iodide, lead iodide, cupric sulphide, cadmium iodide, and freshly-cleaved mica, on the (001) plane of iodine, and on the (010) plane of mercuric iodide.

Notes: Summary Coda waves viz. the tail portion of an earthquake record have been observed and analysed byCarder, Macelwane and others. They showed that the periods of such waves increase with the increase of epicentral distances.Carder observed that these waves have very little transverse component so that these may be considered as of the type of Rayleigh waves. RecentlyOmote showed that the Coda waves contain three periodsT 1,T 2,T 3 of whichT 1 increases with epi-central distances as observed by previous observers. ButT 2,T 3 remain constant for all earthquakes from different epicentral distances.Omote tried to explain this phenomenon by considering that the surface of the earth consists of several layers andT 2,T 3 are free oscillation periods of the surface layers.T 1 period has been explained bySezawa and also byJeffreys which has been shown byGutenberg. The author has attempted to explain the periodsT 2,T 3 by considering passage of cracks at the focal region. The Rayleigh wave character of Coda waves and low velocity of such waves have been explained.

Notes: Summary Differences between epicenter azimuths and the direction of arrival of firstP-waves are determined from the horizontal seismograms of Djakarta station. Systematic azimuth deviations of more than 15° are encountered in the NW through N to SE azimuths. Azimuth deviations caused by a discontinuity dipping 5, 10 and 15° and with a ratio of velocity of longitudinal waves at either side of the discontinuity of 1.23, 1.38 and 1.52 are calculated. The most simple model suitable to the observed data is that of a discontinuity with a velocity ratio of about 1.5, dipping 8–10° in a N 10° E direction. In the S and W directions of Djakarta no dipping discontinuity is needed to account for the few observed data in these quadrants.

Notes: Riassunto Fino ad oggi sono apparse solo teorie elettrogeosmotiche transitorie unidimensionali. Quì risolviamo un problema del genere bidimensionale, con elettrodi verticali cilindrici. Le curve rappresentative delle portate d'acqua catodicaq K a cui perveniamo, denotano diminuzioni abbastanza rapide fino ai tempi dell' ordine dei «tempi elettrodici τ», (t=τ), portate che poi diminuiscono in modo molto lento. Si riscontrano quì più estesi «pianerottoli»q K che non quelli delle monodimensionalità (t=τ/9). Inoltre, col crescere dei rapporti distanze eteropolari-raggi catodici, o col diminuire dei raggi catodici, tali portate (che si compongono dei contributi dei singoli anodi) s'incrementano nel modo diagrammato.

Notes: Summary Calculations are performed to determine the time variation of supersaturation during cloud formation. It is shown that a simple expression can be used to obtain the maximum supersaturation (and hence the number of nuclei activated) as a function of updraught velocity and nucleus spectra insert omitted portion of copy reported in Part 1 and it isshown that they lead to cloud droplet concentrations which agree with those actually observed.

Notes: Summary The development of the law of radiation, and his consequences, shortly exposed.

Notes: Summary Certain problems of synoptic meteorology relating to the nature of the large quasi-stationary cyclonic and anticyclonic centers aloft are examined from the standpoint of an hypothesis which seeks to connect their maintenance with that of the smaller transient disturbances. The suggested link between these two scales of eddies is in many ways similar to that operating in the general circulaton in order to account for the sustained existence of the circumpolar mean zonal motions, according to the more modern concepts. Newer views concerning the dynamcis of large convective processes, and the essential nonlinearity of the laws governing motions in the atmosphere, figure importantly in the arguments advanced.

Notes: Zusammenfassung Infolge der Verhinderung der Metamorphose durch KClO4 treten bei den Kaulquappen vonXenopus laevis nach etwa 1 1/2 jähriger Versuchsdauer atypische Gewebsbildungen auf, und zwar: krebsartige Wucherungen der larvalen Epidermis und des Kiemenepithels, knötchenförmige Verdickungen des Mitteldarmepithels, welche zu Ulcerationen und Darmdurchbrüchen führen, mesenehymale Wucherungen, die zum Teil larvale Blutgefäße und Nerven durchsetzen. Der larvale Knorpel zeigt zum Teil eigenartige Degenerationserscheinungen mit kugelförmigen Eiweißablagerungen im Plasma, zum Teil aber auch Wucherungen (Chondroblastome und chondroplastische Sarkome). Die Schilddrüse der Versuchstiere hat adenomatösen Charakter mit Neigung zu heterotopem Wachstum. Je weiter die Verlagerung erfolgt, desto atypischer wird der Follikelbau. Versuche mit KClO4 an metamorphosierten Krallenfröschen von gleicher Versuchsdauer hatten niemals atypische Wucherungen zur Folge.

Notes: Summary 1. The mitotic peculiarity of the ventricle has been studied. 2. Diffused mitotic activity is noticed throughout the tissue matrix. No definite mitotic zone is seen. The total mitotic activity varies in the different regions as well as in different times of growth. 3. Except in 3 day heart, the rate of cell division is always more in the central area. 4. The ratio of dividing nuclei to resting nuclei in the peripheral region of 3 day heart is higher than that in the central region. 5. The most important item in the individuation of this organ is that the total percentage of dividing nuclei in the different stages, always present a slender figure. However, the cell increase is continuous. 6. The frequency is at its maximum. (11.03%) in 13 day heart, and the minimum (3.09%) in 21 day heart. The percentage of divisional figures in other stages fluctuates in between them. The cell increase in the heart continues even after hatching.

Notes: Summary 1. Optic vesicle from stage 24 (Nieuwkoop andFaber 1956) can induce lens in the ectoderm from early to mid grastrula, and even from ventral ectoderm of a tail bud stage. 2. Lenses were induced from early ectoderm cultured over night before grafting even though it remained thick. 3. For lens formation and its differentiation, prolonged contact with the optic vesicle seems essential. 4. Lens anlage removed from the influence of the optic vesicle as late as the stage 24 (Nieuwkoop andFaber 1956) and cultured as an explant attached to the head region failed to differentiate. 5. The environment offered by the head region and the headmesoderm plays an important role in determining the lens competence. 6. Xenopus optic vesicle can induce lens from Axolotl ectoderm. 7. There was no instance of retinal regeneration.

Notes: Résumé L'étude plus poussée des cloisons radiaires au sommet du dôme montre que l'hétérogénéité d'amassage dans un ou deux quadrants se produit même avec un croisillon très étroit permettant la libre circulation des Fourmis sur la majeure partie du sommet. Le phénomène de l'amassage hétérogène ne se produit plus si les cloisons radiaires ne vont pas jusqu'au sommet. Si on enlève les croisillons pour les replacer peu après dans la même position, l'amassage maximum se fait soit dans les mêmes quadrants, soit dans d'autres. Des cloisons circulaires concentriques sont rapidement comblées jusqu'au bord. Des cloisons rectangulaires verticales implantées à la périphérie du dôme, tangentiellement aux contours, donnent lieu à un amassage important de brindilles en amont, jamais en aval. L'auteur propose, pour expliquer ces faits, diverses hypothèses. On a étudié aussi les parcours individuels des Fourmis transporteuses de brindilles, au cours de leur ascension du dôme. La moitié portent les brindilles près du sommet, les autres les laissent à la périphérie.

Notes: Résumé La glande mandibulaire deCalotermes flavicollis est constituée de deux types distincts de cellules: des grandes cellules sécrétrices dont chacune déverse son produit de sécrétion à l'extérieur par l'intermédiaire d'un canalicule, et des petites cellules centrales. Au moment de la mue, les canalicules sont rejetés, et les petites cellules élaborent les nouveaux canalicules effectuant une migration centrifuge, puis dégénèrent. Dès l'éclosion, la glande mandibulaire est différenciée. Au cours du développement post-embryonnaire, elle augmente de taille, sans que son anatomie varie. Entre les différentes castes, les variations sont peu co nsidérables, mais le développement de la glande est maximum chez les sexués fonctionnels, imaginaux et néoténiques.

Notes: Summary At Westbank, British Columbia, the red antFormica subnitens Creighton obtained food from two primary sources: animal tissues and liquids containing sugar. Animal tissues were of insects, and those that formed the largest part of the diet of the ants were other ants, Coleoptera, and Lepidoptera. Hemiptera, Homoptera, and Orthoptera were taken in lesser numbers. The number of insects captured per day varied depending on the number of ants foraging. The number captured throughout the summer varied with the requirements of the ant brood. The ants used plant secretions from May to early June as a source of sugar. From June until September they collected honey dew from 10 species of aphids and one species of Membracidae.

Notes: Résumé Macrotermes gilvus est fréquent dans les rizières de la plaine du Mékong, inondées plusieurs mois chaque année. L'architecture des nids est décrite et comparée à celle d'autres régions. Le problème de l'alimentation des Termites pendant les hautes eaux est examiné; il semble que les meules à champignons jouent le rôle de réserves alimentaires, permettant la survie des sociétés.

Notes: Summary 1. Larval eclosion and the conditions of growth of young larvae ofMyrmica have been examined by observation and experiment. 2. No structural organisation of the egg mass has been observed which would cause the growth and development towards either dormancy or non-dormancy, of larvae derived from any particular group of eggs. 3. First instar larvae are not ‘distinguished’ from eggs by workers. 4. First instar larvae feed on adjacent eggs in the egg mass. At least one egg is eaten to enable the larva to survice, and many more can be eaten if available. 5. Second instar larvae are ‘detected’ by workers and removed from the egg mass. 6. In a group of larvae those which reach the second instar in advance of the rest gain the advantage of worker attention and feeding, and are directed towards non-dormancy. 7. The brood rearing efficiency of workers varies with seasonal condition and temperature. The presence of brood at other stages of development may affect the survival of young larvae. 8. These results are discussed in relation to colonial efficiency.

Notes: Summary Recently one of the authors introduced for a polydisperse aerosol the useful concept of the equivalent radius which is computed from a monodisperse substitute aerosol with the same fraction of charged nuclei as the actual. In this paper the result of a theoretical and experimental investigation into the agreement between equivalent and average radius of polydisperse aerosols are presented. It is shown that for normal conditions as is to be expected in practice the equivalent radius represents a very good estimate of the average size of submicron particles in polydisperse aerosols.

Notes: Zusammenfassung Für die regionale Klassifikation der Witterungslagen in Gebieten von der Grösse des Alpenraumes wird ein Klassifikationsschema vorgeschlagen, welches auf der Grundlage der im Buch vonFlohn: «Witterung und Klima in Mitteleuropa» veröffentlichten Klassifikation vonLauscher aufgebaut ist. DasLauscher'sche Schema wird von 5 auf 6 Klassen und von 17 auf 33 Typen erweitert wodurch es allgemein für beliebige Gebiete verwendbar wird und eine übersichtliche Charakterisierung der Witterungslage gibt. In der Verschlüsselung durch zwei Ziffern wird sowohl der Witterungscharakter als auch die vorherrschende Strömungsrichtung angegeben.

Notes: Summary The note presents results of five years measurements of circum-global radiation in Dublin with two Bellani spherical pyranometers constructed and supplied by the Physikalisch-Meteorologische Observatorium in Davos. It was found that the agreement of these remarkably simple instruments is very good over the whole period and that they are most suitable and convenient for climatological stations.

Notes: Résumé La marche annuelle de l'intensité du vent en Grèce est étudiée d'après les données anémologiques de 31 stations. Les stations considerées ont été classifiées en 6 types selon la marche annuelle de l'intensité du vent; les raisons qui justifient cette classification sont discutées. L'amplitude annuelle de l'intensité du vent est plus grande aux régions insulaires et littorales qu'à l'intérieur de la Peninsule Héllénique.

Notes: Summary The Southern Oscillation in air pressure may be described primarily as an air pressure balance whose scales are centred near Djakarta (Indonesia) and near Easter Island (South Pacific Ocean) respectively. A synoptic station was established at Easter Island July 1, 1949. 1) The 8 twelve-monthly air pressure values of Djakarta and Easter Island from the period July 1949 up to July 1957 have been correlated with the simultaneous air pressure values at 289 stations throughout the world; 2) The 7 twelve-monthly air pressure values of Djakarta and Easter Island from the period July 1949 up to July 1956 have been correlated with the simultaneous air pressure values at 65 grid points in North Asia and from the period July 1950 up to July 1957 with simultaneous air pressure values at 32 grid points in Africa; 3) At least 5 twelve-monthly air pressure values of Djakarta and Easter Island have been correlated with simultaneous air pressure values at 159 grid points between latitudes 20° and 60° S (Southern Hemisphere Project, Weather Bureau, Pretoria). The latter coefficients obtained, being less reliable, have been used only indicatively. The 545 correlation coefficients have been plotted on world charts and isopleths of the correlation coefficients with the values −0.9,; −0.7; −0.4; 0; +0.4; +0.7 and +0.9 have been drawn (Fig. 1 and 2). The patterns of the isopleths on both maps are very much alike. This is due, of course, to the fact that the coefficient of correlation between Djakarta and Easter Island air pressure deviations reaches a value as high as −0.93. From these pictures may be inferred that the Southern Oscillation acts for the greater part as a stationary wave and for the rest as a progressive wave. Another prominent feature of the Southern Oscillation, shown by the pictures, is that the Easter Island scale is meridionally developed, whereas the Djakarta scale is mainly zonally developed, especially along the equator. It is shown to be very probable that the arctic and antarctic regions both cooperate with the Djakarta region, thus stressing an undeniable overall zonal symmetry of the two patterns. A first impression is obtained of the kind of encroachment of the antarctic circulation on the Southern Oscillation. The well detailed patterns in the northern moderate and high latitudes call up the idea of the planetary waves in the zonal current which normally flows through these latitudes and the question is raised whether blocking action is stimulated when the Southern Oscillation is well developped. Similar indications are obtained from the still rather provisional and rough patterns in the southern moderate and high latitudes.

Notes: Summary The study presents new evidence for the fact that approximately two years prior to the occurrence of maxima and minima of the sunspots, also 1 1/4 to 2 years after the occurrence of maxima, the subtropical high-pressure belts are strengthened and shifted toward the poles, and further that the pressure gradient increases from the high-pressure belt toward the polar region in the summer of the Northern Hemisphere. Based on the summerly amounts of precipitation in Central Europe and average summerly atmospheric pressures in Edinburgh, the intervals of the sunspot cycle, during which the subtropical high-pressure belt is shifted toward the poles, are determined more precisely. The distance of beginning and end of these intervals from the nearest sunspot extreme is expressed in fractions of the distance from the preceding sunspot extreme to the following one, rather than in years. Thus, the departures in anomalous sunspot cycles find their explanation. Finally a chart shows the average annual rings of 10 Central European spruces during a period of almost 200 years. This chart clearly demonstrates the incorrectness of the assertion that the 11-years' sunspot period can be found in annual rings of old trees. This is at least not true in Central Europe. On the other hand the chart expresses well the double or triple variation of precipitations within the sunspot cycle.

Notes: Zusammenfassung Bei der Prüfung der Voraussetzungen, unter welchen die sogenannten «Wachstumskurven» für Lösungströpfchen abgeleitet wurden, kommt man zu dem Ergebnis, dass diese Kurven nur im Falle des Gleichgewichts und nur auf Lösungströfchen mit dem Radiusr≥0.1 μ im Gebiete hoher Feuchten angewendet werden sollten. Da die Bezeichnung «Wachstumskurve» irreführend ist, wird empfohlen, dem GebrauchB. J. Mason's (Physics of Clouds) folgend, diesen Ausdruck prinzipiell durch die Bezeichnung «Gleichgewichtskurve» zu ersetzen. Desgleichen sollten alle für diese Gleichung definierten Grössen wie kritische übersättigung, potentieller Radius und kritischer Radius so umbenannt werden, dass aus der neuen Bezeichnung hervorgeht, dass es sich um Grössen im thermodynamischen Gleichgewicht handelt. Eine Überlegung weist nach, dass in der Regel bei jungen Wolken und Laboratoriumsversuchen, sobald die Feuchtesättigung überschritten wird, die Voraussetzung des Gleichgewichts nicht erfüllt ist. Es wird besonders darauf hingewiesen, dass die Vorstellung, dass die Übersättigung in der Umgebung eines Kerns mindestens seine kritische Gleichgewichtsübersättigung erreicht haben muss, damit der Kern über seinen kritischen Gleichgewichtsradius anwachsen kann, mit dem Experiment in der Mischwolkenkammer nicht in Einklang gebracht werden kann. Die Übersättigung, welche erforderlich ist, in 60 bis 120 Sekundenüber 50% aller Aitkenkerne eines natürlichen Aerosols zu Tröpfchen anwachsen zu lassen, liegt zwischen 2 und 10‰. Der Betrag der notwendigen Übersättigung scheint von der Zeit und der Kerndichte, vielleicht auch den Dimensionen der Kammer und der Temperatur, nicht aber von der chemischen Beschaffenheit des Kernes abzuhängen, da bei den Versuchen die annähernd gleichen Ergebnisse erzielt wurden, unabhängig davon, ob die Kondensation von Wasseroder Benzindampf erfolgt.

Notes: Summary From a study of the variations in potential gradient at Eskdalemuir, Scotland, it is shown that the radioactivity there has roughly doubled during the past six years; in other words, a radioactive contamination equal in activity to the natural background has occurred. Calculations indicate that only some 2% of this contamination can be ascribed to world-wide fall-out following thermonuclear explosions; the remainder must have been generated locally. The obvious sources are the atomic stations — notably Windscale — in Cumberland, and it is considered that, apart from the accident in October 1957, Windscale has leaked radioactive material ever since it first came into operation. The resultant contamination is very considerable and its relation to danger levels is discussed.

Notes: Zusammenfassung Ausgehend von derEmden'schen Theorie der äquatorialen Beschleunigung der Sonne und einer früheren Anwendung derselben auf den Planeten Jupiter, wird auch die Beschleunigung bei Saturn hier erstmalig diskutiert und der Versuch gemacht, dieselbe Theorie zur Erklärung der Ostabweichung der Kontinente der Erde im äquatorialen Gebiet anzuwenden. Das ist nur möglich, wenn man 1.) auf die archaische Periode der Erdentwicklung zurückgreift, bei der aber die wesentlichen Höhenunterschiede der Erdoberfläche schon ausgebildet waren, 2.) der Pol im wesentlichen die jetzige Lage hatte und 3.) der Reibungskoeffizient der festen Erdkruste aber wesentlich geringer war: 1014 gegen etwa 1020 c.g.s.

Notes: Zusammenfassung Gegeben ist ein festes, elastisches Medium, das aus homogenen, isotropen, planparallelen Schichten aufgebaut ist. Im Innern einer Schicht wird ein punktförmiger Störungsherd von Multipolcharakter angenommen. Die Störung setzt zur Zeitt=0 ein. Unter Anwendung der Laplace-Transformation werden nach dem Verfahren vonCagniard «Exponentialkoeffizienten» und «Übertragungsfaktoren» berechnet, die gestatten, die elastischen Verschiebungen der an den verschiedenen Unstetigkeitsflächen reflektierten und gebrochenen Wellen zu bestimmen.

Notes: Summary By means of the long-period records at Uppsala and Kiruna of thirteen specially selected earthquakes, the Love and Rayleigh wave dispersion is determined for all oceans and all continents except for South America. The observations have given information on crustal structure along several paths, not investigated earlier; in other cases, they have confirmed earlier results. The methods are discussed. The results for oceanic areas are summarized in the following table: The observations demonstrate the oceanic structure of the central Arctic area as well as the complete similarity of the Atlantic and Pacific bottom structure. Continental dispersion curves are determined for very long paths over Euro-Asia and for the hitherto longest path over North America as well as for a path crossing Africa. These observations indicate an average crust about 10–15 km thicker along the Euro-Asiatic path than along the North American path, whereas there is perfect agreement between the North American and the African continent. A shear-wave velocity of 4.3–4.4 km/sec is obtained for the upper part of the mantle under the continents. Further conclusions must await the computation of a greater number of theoretical dispersion curves.

Notes: Summary Condensation nuclei which grow into droplets in natural clouds constitute only a small fraction of the total population of nuclei, since they must be activated at low supersaturations (〈1%). Such nuclei cannot readily be measured by the usual expansion methods. A chemical diffusion method is described in which water vapour and HCl vapour diffuse between a water surface and an aqueous HCl solution; this produces the continuous small supersaturations required to study these «cloud nuclei». Nucleus numbers are obtained photographically. Results of observations made by this method during the period April–August 1958 are presented and discussed; they suggest that the main source of cloud nuclei is the dry land surface.

Notes: Résumé Les moyennes mensuelles des températures publiées parF. Eredia pour 482 stations ont servi au calcul de la phase de la composante annuelle par la technique deYakovlev plus expéditive que la méthode d'analyseLabrouste. L'examen de la répartition géographique de la phase calculée fait ressortir les influences de l'orographie, de l'orientation des côtes et de la latitude sur la mise en place dans le temps de la fraction permanente de la marche annuelle des températures.

Notes: Summary The possibility of the use of measurements of the electrolytical conductivity of precipitation water as an aid to the chemical analysis has been examined. The measured conductivity of rain-water and of water obtained by melting snow and rime was of the order of magnitude of that for more or less good distilled water, apart from some exceptions. Considerable variations of the conductivity of rain-water continuously measured during rainfalls were observed. The relation between the conductivity and the chemical composition of the precipitation water was discussed by using the data of the Scandinavian precipitation-chemistry project. The importance of pH measurements was also shown by this consideration.

Notes: Summary The diffusion of gaseous radioiodine vapour to surfaces is controlled by boundary layer effects, and diffusion to the walls of a tube is in good agreement with theory. In the presence of condensation nuclei the behaviour of the radioiodine depends on the amount of iodine carrier present. With no carrier the radioiodine appears to undergo adsorption on the nuclei.

Notes: Summary The conditions for sliding over artificial joint surfaces have been studied experimentally by cutting rock cylinders at various angles to their axes and studying slip over these surfaces in a triaxial testing apparatus. The types of joint used were: (i) filled with plaster to simulate a soft joint filling, (ii) bare surfaces ground approximately flat, and (iii) natural surfaces across which shear failure had taken place. The results agreed reasonably well with the simple theory for a constant coefficient of friction. Measured coefficients of friction lie in the range 0.5–0.8 and differ by surprisingly little between the various surfaces. The surfaces across which sliding has taken place exhibit interesting slickenside phenomena. Subsidiary failures frequently occur which cut across the joint surfaces.

Notes: Zusammenfassung Es wird das Interpretationsproblem der Refraktionsseismik in einem einachsig inhomogenen Körper allgemein behandelt und exakt gelöst.

Notes: Summary The analysis of the readings taken with aWorden gravimeter during fieldwork over a period of four years when compared with tests in a laboratory shows that its behaviour is not dependent on vibration and that the drift can be separated into two distinct parts; an isothermal drift and a thermal drift. The former is remarkably constant over short and long periods of time and is of the order of 0.01 mgal/hour. The latter is complicated and is dependent on the rate of change of the ambient temperature being different in size and sign, for quick and slow changes of temperature. The sensitivity changes slowly with time, 0.1% per year, and is only slightly affected by temperature. Tares or jumps in the readings are very rare. Modifications to the meter are suggested, consisting of the inclusion of a rheostat in the lighting circuit and the attachment of a thermometer to the outside of the instrument. In order to keep the correction for drift to a small size and to increase the accuracy, returns to a base station should be made according to changes in the ambient temperature rather than at fixed time intervals.

Notes: Summary This paper presents the study of variations of the solar radiation and the blueness of the sky during the eclipse of June 30, 1954 at Athens. The comparison of the solar radiation march during the eclipse day to that of the two preceding and the two following days of the eclipse-all five days were almost identical from the standpoint of weather—proved that the direct solar radiation and the total (sky and sun) radiation underwent a considerable decrease during the phenomenon. The blueness of the sky also underwent a significant change, especially at the maximum of the eclipse.

Notes: Summary Measurements of the concentration of small ions near the ground showed that large numbers of «ions» of sign opposite to that of the potential gradient were produced in rain. A series of laboratory experiments designed to examine the processes involved, showed that the ions were produced by the disintegration of films of water when drops splash, and a determination was made of the dependence of the charge released by individual drops on the parameters involved. The paper will be published elsewhere.

Notes: Summary Spectral analysis of atmospheric emission and absorption in the translucent region 8–13 microns from observations made in London and in the relatively clean air near Ascot (Berks) has confirmed the existence of a continuous extinction in the lowest 2 Km of the atmosphere which outweighs the selective extinction due to gaseous constituents. This continuous extinction must be due to atmospheric aerosol, or to the far wings of distant, strong gaseous absorption lines. Our provisional conclusions are that the former cause predominates in London, but is unimportant near Ascot where the observed extinction must be mainly due to the latter cause. Attention is drawn to the important contribution which the continuum can make to the heat balance of the atmosphere below 2 Km. The report will appear elsewhere.

Notes: Summary A technique is described which allows the study of the concentration of silver-iodide particles produced by a ground generator. It consists of marking these particles with Iodine 131, then filtering the air at the required places with air-borne filters. The iodine is extracted chemically, concentrated in a very small silver iodide disc which is then placed upon a nulcear emulsion. After two weeks the activity is measured by electron track counting. Limitations of the method are given. The paper has been published in extenso in the «Zeitschrift für angewandte Mathematik and Physik» (ZAMP), XIa, p. 375, 1958.

Notes: Summary The scheme of a seism caused by the slipping of a transcurrent fault is examined and the law of the variation of the seismic superficial displacement v/s distance to the fault is given, assuming that no extra stress is produced at the base of the broken layer. Taking a simple example for the preseismical strain, it is possible to find an order of magnitude of the extent of the fault in depth. An application to the San Francisco seism of 1906 gives a depth of about 13 km.

Notes: Summary The figures of equilibrium independant from the law of density in their interior can be characterized by the remarkable property that the absolute value of the «shape-parameter» must be a minimum. This gives an equation between the flattening and the twoStokes constant ε and δ, by which the ∞3 figures of equilibrium can be selected from the ∞4 solutions ofHelmert's equations for a given mass. Each inhomogeneous spheroidical figure of equilibrium is determined unequivocally by the mass and the shape of its free surface or by the mass and three physical parameters; the law of density is strictly individual. From the threefold infinite multiplicity of the figures of equilibrium linear series are to find out with two fixed physical parameters or you can compute a series of figures with a common level surface or the series built by all level surface of a given figure of equilibrium. Though the moments of inertia are notStokes constants the normal spheroid of earth unequivocally defined by ω,W 0 andC can be determined without hypotheses, because in the series (ω,K) also the moments of inertia and the mechanical ellipticity are constant. Therefore the empirically known mechanical ellipticity can be substituted by the static flattening returning to the homogenous figure in the beginning of the series. Of course the determination of the normal spheroid of earth demands the knowledge of gravity in equator and of the equator-axis instead of the unknown mass of earch series (ω,W 0), (ω,K) and (K,W 0), which intersect in the normal spheroid, are discussed. Also the boundary surface of the figures of equilibrium in the Cartesian system of the coordinatesa, α andh m is discussed; this surface is determined byf=−3a2/2.

Notes: Zusammenfassung Es werden Messanordnungen beschrieben, die für geoelektrische Tiefsondierungen bis ungefähr 4000 m geeignet sind. Anschliessend werden die erzielten Messergebnisse besprochen. Die Übereinstimmung zwischen der geoelektrischen Prognose und dem Ergebnis der Bohrung ist eine sehr gute. Die Abweichung schwankt im Mittel um ungefähr 8–13%.

Notes: Zusammenfassung Messwerte russischer Stationen beweisen die Existenz eines «Kontinental-Effektes» bei der maximalen Elektronendichte derF2-Schicht. Im Sommer besteht im Innern des asiatischen Kontinents vorzugsweise eine höhere Konzentration bei Tag; andererseits fehlt dort die sogenannte «Abend-Konzentration».

Notes: Riassunto Coi dati rilevati nel Settembre 1924 dalla ≪Mario Bianco≫ a Nord dello Stretto di Messina si determinano i coefficienti di diffusione turbolenta, longitudinale e trasversale, per gli strati superficiali della corrente ≪scendente≫ convogliata dallo Stretto medesimo: ottenendo valori in buon accordo con quelli calcolati da altri AA. per altre correnti marine. Inoltre si forniscono elementi sull'estensione per diffusione in profondità delle acque ioniche penetrate nel Tirreno.

Notes: Summary Annual average results of rainwater analysis, carried out byC. Junge at about 60 stations of the United States sampling network are used in an attempt to correlate the ionic species present in rain, as a general contribution to atmospheric chemicstry. Correlation with physical parameters is attempted at the same time in some cases, and the resulting trends discussed. The results obtained are presented in the general form of linear and planar correlation, and linear regression coefficients.

Notes: Summary Following a recent hypothesis on the role of activated sodium chloride particles as possible condensation and sublimation nuclei, an analysis of data given byC. Junge on the chemical composition of aerosols, is made. It is established that all reported giant nuclei fall into three distinct categories of composition and that within each of these categories the ratio of the sums of anions to the sums of cations for constituents for which analyses were made, remains remarkably constant throughout the days of sampling, and for both geographic positions at which sampling has been carried out. A dependence of the hydroxide-carbonate content, on that of nitrate is also indicated in the «alkaline» nuclei. The system is treated as a saturated solution, and it is shown by the procedure of continuous variations that singularities occur at particular ratios of the prevalent chemical groups in solution, possibly indicating formation of complex species. This, together with the presence of double salts in the solid phase may be partly the reason for the constancy of ratio of sums in the groups of particles studied byJunge, while the grouping itself may depend on the origin and subsequent transformations of the particles.

Notes: Summary Following a recent hypothesis on the role of activated sodium chloride particles as potential nuclei of atmospheric precipitation, further analysis is made of average annual data due toC. Junge on the chemical composition of rainwater salts, and correlation of some parameters with the total amount of rainfall is attempted. It is found that the results obtained are in agreement with the proposed role of activated sodium chloride as a nucleus of a substantial part of the atmospheric precipitation.

Notes: Summary The influence of heterogeneity on the determination of the diffusion coefficient by the dynamic method is investigated for polydisperse aerosols with various Gaussian particle size distributions. It is further shown, theoretically and experimentally, that the misapplication ofGormley's formula to polydisperse aerosols must give different apparent diffusion coefficients when they are determined with the same air-flow by two batteries having different dimensions and numbers of channels. On the other hand, the apparent diffusion coefficients as measured by two diffusion batteries with different constants can be equalized by selecting the air-flows through the batteries so that (a/3.77bLc)Q for the two batteries is constant wherea, b, L are the dimensions of the channels,c their number andQ the air-flow. The dependence of the apparent diffusion coefficient on air-flow was tested in a new experimental set-up with reduced length of connecting tubing of anti-static rubber. The results of these experiments confirm previous findings.

Notes: Zusammenfassung In der Nullschicht, die identisch ist mit der Schicht des hochtroposphärischen Windmaximums, kehren sich im Mittel die großräumigen Vertikalbewegungen um und herrschen die stärksten ageostrophischen Windkomponenten zum hohen Druck hin. Diese übergradientischen Winde in der Nullschicht können zur Erklärung der thermisch-indirekten Zirkulation der planetarischen Westwinddrift herangezogen werden. Ein echtes persistentes Windminimum hat ebenfalls Nullschichtcharakter mit ageotrophischem Massenfluß zum tiefen Druck hin (Nullschicht 2. Art mit negativem Nullschichteffekt). Eine persistente Schicht mit verschwindendem horizontalen Druckgradienten kann vielleicht als Nullschicht 3. Art bezeichnet werden, die keinen Nullschichteffekt aufweist. Sie kehrt die großräumigen Vertikalbewegungen nicht direkt um, sondern trennt übereinanderliegende Bereiche mit voneinander unabhängiger Vertikalbewegung. Alle drei Arten von Nullschichten sind im Zusammenhang mit der allgemeinen Zirkulation von großer Bedeutung.

Notes: Summary A survey is given on the present status of knowledge about the chemical composition of atmospheric aerosols. Results on the size distribution and the physical structure of the nuclei provide the necessary basis for an under-standing of their chemistry. Very little is known about the chemistry of particles smaller than 0.1μ. For larger particles micro-analyses show the presence of sulfate, nitrate, chloride, sodium and ammonium which varies in a characteristic way with the size of the particles. The sea spray component can be isolated. Data from rain water analyses are used to obtain information on the large scale distribution of these components and their sources. Some remarks about the fraction of the particles acting as true condensation nuclei and the radioactivity will conclude the paper. The subject has been already developed in detail inAdvances of Geophysics, Vol. 4 (edited byH. E. Landsberg & J. van Miechem), Academic Press Inc., New York, 1958.

Notes: Summary Various recent results on the analyses of rain water, ice samples from Greenland and the SO2 and H2S concentration in air are combined to obtain a picture of the sulfur budget and cycle in the atmosphere. Estimates are presented on the role of industrial sulfur on a global basis. The cycle of sulfur is complicated, but is an interesting example of a trace substance which is present as gas and aerosol. The importance of sulfate for the composition of atmospheric nuclei in remote places is pointed out. The paper will be published elsewhere.

Notes: Summary Although the bubble chamber was only invented byGlaser in 1952, there are today over a hundred chambers in use in physics laboratories throughout the world. In the field of high energy physics they have proved to be an invaluable tool and already much information has been obtained concerning very energetic particle interactions and properties of «strange» particles by the use of both hydrocarbon and liquid hydrogen chambers.

Notes: Summary The properties of condensation nuclei generated at a metal point corona discharge have been examined. The threshold voltages for nucleus production and for small ion production are the same. The fraction of the nuclei which is charged is initially small and becomes virtually zero after a few seconds. It is demonstrated that in the non-uniform field near the point there is a force on the nuclei driving them to the point. From determinations of the diffusion coefficient it is tentatively concluded that a portion at least of the nuclei are originally of molecular size. No satisfactory explanation has been found for certain anomalous features of the variations in size and in concentration of the nuclei with time after production.

Notes: Summary Brief report on an experiment actually in progress.