ALBERT

Notes: A panel of speakers, knowledgeable in the problems of photogrammetry in the Third World, led a discussion which considered the place of sophisticated photogrammetric equipment in the Third World, problems of technician and management training, the desire for self reliance, and the needs of map revision.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméUne confrontation entre photogrammètres sur le sujet photogrammétrie et tiers-monde; équipement, instruction des techniciens, problèmes d'organisation, désir d'autonomie, révision des cartes.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEin Forum von Kennern der Probleme der Dritten Welt führte eine Diskussion über den Platz moderner Geräteausrüstungen in diesen Ländern, über Probleme der Ausbildung von Technikern und Führungskadern und erörterte den Wunsch nach Selbstbestätigung und die Notwendigkeit zur Laufendhaltung von Karten.

Notes: The problems associated with the depiction of a particular irrigation area by both line map and orthophotomap are described and the results compared.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméDes problèmes soulevés par la description d'une aire d'irrigation à l'aide d'une carte ou d'une ortho-photocarte: comparaison des résultats.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung der Probleme, die bei Auswahl sines Bewässerungsgebietes an Hand von Strich- und Orthophotokarten auftraten und Vergleich der Ergebnisse.

Notes: In 1981, a metric camera will be launched into space on a European Space Agency Spacelab mission. This paper examines the specification for this mission and the expected results. Other developments are also considered. These include the American large format camera and long focal length imaging systems.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméEn 1981, une chambre métrique sera lancée dans l'espace (mission Spacelab de l'organisation européenne spatiale). On examine ici les buts et les résultats attendus, ainsi que de futurs développements; chambre américaine à grand format, systèmes à longues focales.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Jahre 1981 soll sich an Bord des Europäischen Spacelab-Satelliten eine Messkammer befinden. Im Artikel werden die Anforderungen an dieses Projekt und die zu erwartenden Ergebnisse diskutiert. Desgleichen werden auch andere Entwicklungen, worunter sich die amerikanische Grossformat-Kammer und langbrennweitige Systeme befinden, erörtert.

Notes: Many attempts have been made to use various types of photography for traffic studies. The problems most frequently encountered are the expense involved in obtaining the photography and the time consuming and, hence, expensive operation of collecting the required data from the photography. This paper discusses the problems associated with various types of photography and describes a study which has been carried out to evaluate the potential of 16 mm and 35 mm time lapse photography taken from a helicopter. The accuracy of two dimensional co-ordinate transformation systems for collecting the required data from the photography is also described. Finally, recommendations are made regarding the most suitable type of photography and the most convenient and accurate transformation system to use when it is required to analyse the traffic flow data at complex urban and suburban intersections.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméBeaucoup de tentatives ont déjàété faites pour étudier les problèmes de circulation par photographie: les difficultés sont le coût de la photographie, les délais d'obtention et le coût du dépouillement. On examine ici les possibilités offertes par divers types de photographies et on donne les résultats d'une étude entreprise pour évaluer l'intérêt de la solution; camera 16 mm ou 35 mm plus hélicoptère. On précise ici l'exactitude requise pour les transformations de coordonnées. On conclut par toute une série de recommandations.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs gibt sehr viele Versuche zur Verwendung verschiedener Arten der Photographie für Verkehrsstudien. Die am häufigsten auftretenden Probleme sind die Kosten und der Zeitaufwand der Photographie, wodurch die Datenerfassung aus Photos teuer wird. Im Artikel werden die Probleme beschrieben, die bei Anwendung verschiedener photographischer Aufnahmen auftraten. Ferner wird ein Versuch mit 16 mm und 35 mm Zeitrafferaufnahmen aus dem Hubschrauber erörtert. Beschreibung der Genauigkeit zweidimensionaler Koordinatentransformationen zur Ermittlung der gewünschten Daten aus Photos. Abschliessend werden Empfehlungen bezüglich der am besten geeigneten photographischen Methode und zur Transformation der Daten gegeben, wenn Verkehrsströme an komplexen Kreuzungen in Städten und Vororten analysiert werden sollen.

Notes: On 17th January, 1978, the Secretary of State for the Environment announced the establishment of a Committee, chaired by Sir David Serpell, with the following terms of reference: “Taking account of the views of users and other interested parties, in the context of national surveying and mapping needs, to consider and make recommendations about the longer term policies and activities of the Ordnance Survey and ways of financing them.” Interested organisations, among them The Photogrammetric Society, were invited to submit evidence to the Committee. The Society's submission is reproduced in full. The Secretary of State has asked the Committee to report, if possible, early in 1979.〈section xml:id="abs1-2"〉〈title type="main"〉SummaryAs has been stated the national survey, comprising as it does the horizontal and vertical control frameworks and the basic scales mapping based upon it, represents (assuming completion of the last named) a priceless national asset, but it is not “money in the bank”. It is an ephemeral and fragile asset which will have been frittered away unless it is constantly maintained, repaired and refurbished; even so it will not last forever. At one time or another the various components will all require replacement eventually. What must be avoided at all costs is a repetition of such culpable neglect that it all needs replacement at the same time. This summarises what is now, and must remain, the prime objective of the Ordnance Survey. Superimposed upon this are the needs to make the survey available, in various forms, to users; to produce small scale mapping; and to collect and disseminate various other forms of topographic data.〈section xml:id="abs1-3"〉〈title type="main"〉Résumé Le 17 Janvier 1978, le secrétaire d'Etat à l'environnement anonçait la création d'une commission, présidée par Sir David Serpell: les objectifs étant précisés de la manière suivante; “Tenant compte des besoins des utilisateurs et des autres parties intéressées aux activités cartographiques, proposer une orientation à long terme de la politique de l'établissement et revoir les modes de financement de l'Ordnance Survey.”Les organisations concernées, et parmi elles la Photogrammetric Society, étaient invitées à entrer en relation avec la commission: on reproduit ici in extenso la déposition de la Photogrammetric Society. Le secrétaire d'Etat a demandéà la commission de remettre son rapport début 1979 si possible.〈section xml:id="abs1-4"〉〈title type="main"〉Zusammenfassung Am 17.1.1978 kündigte der Staatssekretär für Umweltfragen die Gründung eines Komitees unter Vorsitz von Sir David Serpell an, dasfolgende Aufgabe erfüllen soll: “Analyse der Ansichten von Nutzern und anderen interessierten Gruppen bezüglich der nationalen Anforderungen an Vermessungswesen und Kartographie, um daraus Empfehlungen für die längerfristigen Aktivitäten des Ordnance Survey und die Möglichkeiten zur Finanzitrung abzuleiten.” Interessierte Organisationen, darunter die Photogrammetric Society, wurden eingeladen, die Tätigkeit des Komitees zu unterstützen. Für Anfang 1979 soll ein Bericht vorgelegt werden.

Notes: Book review in this ArticleTHE UNITED KINGDOM FROM SPACE (2). By D. J. Carter and H. J. P. Arnold. Space Frontiers Ltd. Havant, Hampshire, 1977.SURVEYS FOR DEVELOPMENT. Edited by J. J. Nossin. Elsevier Scientific Publishing Co. Amsterdam, Oxford, New York, 1977.REMOTE SENSING OF THE TERRESTRIAL ENVIRONMENT. Edited by R. F. Peel, L. F. Curtis and E. C. Barrett. Butterworths, London, 1977.MAPPING FOR FIELD SCIENTISTS. By W. Ritchie, D. A. Tait, M. Wood and R. Wright. David and Charles, Newton Abbot, Devon, 1977.SURVEYING AND PHOTOGRAMMETRY. COMPUTATION FOR CIVIL ENGINEERS. By D. E. Murchison. Newnes–Butterworths, London, 1977.RESOURCE SENSING FROM SPACE: PROSPECTS FOR DEVELOPING COUNTRIES. Report of the Ad Hoc Committee on Remote Sensing for Development. US National Academy of Sciences, Washington, D.C., 1977.MISSION TO EARTH: LANDSAT VIEWS THE WORLD. By N. M. Short, P. D. Lowman, S. C. Freden and W. A. Finch. National Aeronautics and Space Administration, Washington, D.C., 1976.REMOTE SENSING IN GEOMORPHOLOGY. By H. Th. Verstappen. Elsevier Scientific Publishing Company, Amsterdam, Oxford, New York, 1977.

Notes: The paper describes two research projects on the application and value of satellite imagery taken, by ERTS 1 and Skylab, for small scale mapping. It describes the methods used in controlling a block of normal system corrected imagery and the accuracies achieved.The interpretation and evaluation of the imagery are discussed and the results of ERTS 1 and Skylab in this field are compared. Finally, some examples are described where ERTS 1 imagery has proved of practical value as a navigational aid when flying conventional photography and airborne geophysical surveys and for providing base maps when concerned with resource evaluation of poorly mapped areas.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé On présent les résultats de deux projets de recherche sur les applications possibles el la valeur pratique des imageries satellitaires, prises avec ERTS 1 et Skylab en vue de la cartographie à petite échelle. On décrit les méthodes utilisées pour “appuyer” un bloc à imagerie corrigée (système normal) et l'exactitude obtenue. On compare de ce point de vue ERTS 1 et Skylab. Enfin on donne quelques applications pratiques qui se sont révélées utiles: aide à la navigation pour les levés photographiques et géophysiques aériens; établissement de cartes expédiées en vue d'inventaire de régions souscartographiées.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Beschreibung von zwei Forschungsprojekten über die Anwendung und den Nutzen von Satelliten-Bildern, die von ERTS 1 und Skylab aus aufgenommen wurden, für die Herstellung kleinmassstäbiger Karten. Es werden die Verfahren beschrieben, die beim Festpunktanschluss von korrigierten Bildern angewendet wurden. Die dabei erreichten Genauigkeiten werden mitgeteilt. Diskussion der Interpretation und Bewertung der Bilder und Vergleich der diesbezüglichen Ergebnisse von ERTS 1 und Skylab. Schliesslich werden einige Beispiele beschrieben, wo Bilder von ERTS 1 von praktischem Wert als Navigationshilfe zur Luftbildaufnahme und geophysikalischen Lufterkundung und bei Beschaffung von Grundkarten bei der Ressourcenerkundung in kartographisch schwach erfassten Gebieten waren.

Notes: The author reviews the present state of aerial triangulation methods and outlines the requirements for future research which were suggested at the symposium of Commission III of the International Society for Photogrammetry in 1974. He maintains that none of these research topics is very relevant to aerial triangulation as it is practised in Britain today. A combination of complacency, the natural inertia imposed by economic arguments and the higher priorities accorded to younger developments such as automated cartography is conspiring to prevent replacement of adequate but out-dated methods. He considers that there are nevertheless, strong arguments for selecting a newly designed, optimum, modern system, based on a modular approach, which can be introduced on a national basis and made fully available to all interested organisations.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméRevue de l'état actuel des méthodes de triangulation aérienne et rappel des voies de recherches recommandées au symposium de la Commission III de la SIP en 1974. Aucune de ces voies n'a malheureusement de rapport avec ce qui est actuellement pratiqué en Grande Bretagne en matière de triangulation aérienne. Une certaine complaisance, mêlée à une inertie assez naturelle due à des raisons économiques et à la plus grande priorité accordée à des domaines plus neufs comme la cartographie automatique, a perpétué l'emploi des méthodes pertinentes mais désuètes. L'auteur pense qu'il y a de puissants arguments pour qu'on choisisse et mette en oeuvre une méthode moderne, avec approche modulaire dont l'emploi se ferait à l'échelle nationale et à laquelle tout organisme intéressé pourrait recourir.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer Autor referiert über den gegenwärtigen Stand der Verfahren der Aerotriangulation und skizziert die Anforderungen für künftige Forschungs-arbeiten, die auf dem Symposium der Kommission III der Internationalen Gesellschaft für Photogrammetrie 1974 vorgeschlagen wurden. Er bekräftigt, dass keiner dieser Forschungsgegenstände bezüglich der gegenwärtig in Grossbritannien praktizierten Aerotriangulation relevant ist. Eine Kombination von Selbstzufriedenheit, natürlicher Beschränkung infolge ökonomischer Argumente und der höheren Prioritäten wegen der neueren Entwicklungen z.B. in der automatischen Kartographie verhindert den Ersatz passender, aber unmoderner Verfahren. Der Autor ist der Meinung, dass es trotzdem starke Argumente zur Auswahl eines neuen optimalen, modernen Systems gibt, das auf dem Bausteinprinzip beruht und das auf nationaler Grundlage eingeführt und allen interessierten Organisationen zugänglich gemacht werden kann.

Notes: A plot of relative parallax measurements in a student exercise is proposed for revealing errors in parallax bar readings taken from a stereo-pair of aerial photographs. The sensitivity of the computed heights to measurement error is also evaluated.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn propose un tracé graphique des mesures de parallaxe pour mettre en évidence des erreurs de lecture à la barre de parallaxe.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs wird eine Auswertung relativer Parallaxenmessungen bei einer studentischen Übung vorgeschlagen, um Fehler der an einem Stereomikrometer vorgenommenen Ablesungen aufzudecken, die an Hand eines Luftbildpaars erfolgten. Der Einfluss des Messfehiers auf den Höhenfehler wird ebenfalls abgeschätzt.

Notes: 1:70 000 scale photographs taken over Syria with a Russian AFA topographic camera equipped with a Russar 29b super-wide angle lens have been tested. The tests included (i) the measurement of a field of points using several different instruments and a comparison of the photogrammetrically derived co-ordinates with the values derived by field survey; (ii) the production of plots at 1: 25 000 scale for comparison with a check plot produced from large scale, wide angle photography; and (iii) production of orthophotographs, also at 1: 25 000 scale. Difficulties were experienced with the asymmetrical lens distortion pattern and the variations in illumination and resolution present in the photography. The former were overcome by manufacture of asymmetrical lens distortion correction plates. When this was done, the accuracies attained were comparable to those achieved in previous tests using photographs taken at the same scale with the Wild RC 9 camera equipped with the Super Aviogon I lens and measured on the same or similar types of measuring equipment.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé On décrit ici un test relatif à une couverture aérienne au 1: 70 000 exécutée en Syrie avec une chambre russe AFA dotée d'un super-grand angulaire 29 b. Le test comprenait: la détermination d'un polygone au sol, et la comparaison des determinations géodésiques et des déterminations photogrammétriques; la restitution de parcelles au 1: 25 000 en vue de les comparer avec une parcelle-test provenant de photos à grande échelle; et la réalisation d'ortho-photos au 1: 25 000. La distorsion disymétrique de l'objectif a conduit à quelques difficultés, ainsi que des inégalités d'éclairement et de finesse sur les clichés. On a surmonté les premières en faisant fabriquer des plaques correctives. Ceci fait, l'exactitude atteinte s'est trouvée du même ordre que celle de restitutions provenant des clichés aux même échelles pris avec le Wild RC9 et effectuées dans des conditions très voisines.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Bericht über die Testung von Luftbildern (mb= 70 000), die über Syrien mit einer sowjetischen Überweitwinkelkammer mil einem Russar-Objektiv 29b aufgenommen wurden. Die Untersuchungen umfassten (a) die Aus-messung eines Punktfeldes mit verschiedenen Auswertegeräten und einen Vergleich photogrammetrisch und geodätisch bestimmter Koordinaten, (b) die Durchführung einer Auswertung 1: 25 000 und den Vergleich mit einer aus grossmassstäbigen Weitwinkelbildern abgeleiteten Kontrollkarte, (c) die Herstellung von Orthophotos im Massstab 1: 25 000. Schwierig-keiten resultierten aus der asymmetrischen Objektivverzeichnung und den Variationen in der Bildhelligkeit und -auflösung. Die Verzeichnung konnte durch Herstellung von Kompensationsplatten reduziert werden. Danach waren die erreichten Genauigkeiten mit den in früheren Tests erzielten vergleichbar, bei denen mit einer Wild RC9- Kammer (Super Aviogon I) aufgenommene Luftbilder gleichen Massstabs an denselben oder ühnlichen Auswertegeräten ausgemessen wurden.

Notes: With present day trends towards smaller scale photography for topographic mapping and photomapping, there is an increasing need for high quality photography and a corresponding need for diagnostic information on potential sources of degradation. Hence subjective judgements must be supplemented by quantitative analyses of image quality that go beyond mere determinations of resolution level. A methodology for evaluating three important parameters governing image quality (development, exposure and spatial frequency content) is presented. By sequentially comparing the values measured on production or test photographs with standard values, the faults most commonly responsible for image degradation (such as errors in development and exposure, excessive image motion, vacuum failure and poor camera focus) can be isolated and measured.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLa tendance actuelle en matière de plans topographiques et de photocartes est de diminuer l'échelle de la couverture photo; se fait done jour le besoin d'émulsions de haute qualité et simultanément la nécessité de pouvoir juger objectivement de cette qualité. II faut alors recourir á des analyses quantitatives qui aillent au-delá de la simple mesure du pouvoir de résolution. On présente ici une méthodologie relative au problème de l'évaluation de trois des principaux paramètres effectuant la qualité de l'image (développement, durée d'exposition, résolution de fréquence spatiale). Avec des tests d'homogénéïté on peut alors déceler les variations de qualité, et en particulier déterminer et mesurer les causes d'altération les plus fréquentes (erreurs lors du développement ou lors de la phase d'exposition, filé, défauts internes, qualité médiocre de la chambre).〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBei dem gegenwärtigen Trend, den Bildmassstab zur Herstellung von topographischen Karten und Photokarten zu verkleinern, ergibt sich zunehmend die Notwendigkeit, Hochleistungsphotos aufzunehmen und diagnostische Informationen über mögliche Quellen der Qualitätsverschlechterung zu erlangen. Insbesondere müssen subjektive Bewertungen durch quantitative Analysen der Bildqualität ergänzt werden, die über Bestimmungen des Auflösungsvermögens hinausgehen. Es wird eine Methodologie zur Bewertung von drei wichtigen Parametern (Entwicklung, Belichtung, Inhalt der Orts-frequenz), die die Bildqualität beeinflussen, angegeben. Durch Vergleich der auf Produktionsbildern oder Testbildern gemessenen Werte mit deren Standards können die Fehler, die meistens eine Bildverschlechterung verursachen (wie zum Beispiel Fehler bei der Entwicklung und Belichtung, unzulässige Bildwanderung, ungenügende Planlage oder Kammerabstimmung) aufgedeckt und gemessen werden.

Notes: The development of an automated photographic measuring system (APM) is described. A very accurate laser beam scanning microdensitometer is used to digitise the photographic plate and a series of on line computers analyses the data during scanning. The system is available as a national facility for United Kingdom astronomers and guest investigators.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit un systéme automatisé de saisie de données sur cliché. Un microdensitométre à laser numérise la plaque photographique et les données sont analysées en temps réel par ordinateur. Le systeme est destiné aux astronomes du Royaume Uni et aux chercheurs y séjournant.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines automatisierten photographischen Messsystems (APM). Ein hochgenaues Laser-Mikrodensitometer wird dabei zur Digitalisierung der Bilder benutzt, undeine Serie von On-line-Rechnern analysiert die Daten während der Abtastung. Das System steht für Astronomen im Vereinigten Königreich und anderen Forschern zur Verfügung.

Notes: Two complementary measuring instruments are described which use a very simple principle and which take three dimensional measurements or plots directly from small objects. The first instrument can achieve accuracies of ± 0·3 mm on objects whose largest dimension is 300 mm. The second can achieve ± 0·02 mm on objects smaller than a 25 mm cube.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn présente deux instruments de mesure complémentaires el de principe très simple permettant de relever dans l'espace des coordonnées sur de petits objets, le premier avec une exactitude de ± 0.3 mm sur des objets de dimension inférieure à 300 mm, le second avec une exactitude de ± 0.02 mm sur des objets de dimension inférieure à 25 mm.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung von zwei Zusatzmessgeräten, die auf einem sehr einfachen Prinzip beruhen und mit denen dreidimensionale Messungen oder Auswertungen von kleinen Objekten direkt durchgeführt werden konnen. Mil dem ersten Gerät kann eine Genauigkeit von ± 0,3 mm bei maximalen Objekt abmessungen von 300 mm und mit dem zweiten von ± 0,02 mm bein Objekten, die kleiner als ein 25 mm-Kubus sind, erreicht werden.

Notes: This paper outlines the technical procedures used in commercial orthophotomap production and attempts to identify some of the main differences in technical approach between orthophotomapping and conventional line mapping.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit les techniques industrielles de production d'orthophotocartes et on compare leur emploi avec celui des techniques classiques.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungSkizzierung der Technologien, die bei der kommerziellen Herstellung von Orthofotokarten angewendet werden, wobei versucht wird, die hauptsächlichen Unterschiede der Techniken zur Herstellung von Orthofotokarten und konventionellen Strichkarten aufzudecken.

Notes: This paper investigates the effect of the deviation of measured points from the standard locations when carrying out a relative orientation of a stereomodel. The analytical solution of more than 100 cases was considered and, for each case, the weights for the elements of relative orientation and the correlation coefficients were evaluated. The stability of the solution was studied by calculating the characteristic roots of the matrix of normal equations.It is shown that, theoretically, the solution of the relative orientation problem can always be achieved whenever the locations of the measured points satisfy stated geometrical requirements. However, the reliability of the solution depends on their exact positions in the stereomodel. When the accuracy is too low, in practice there is no solution.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn étudié l'effet sur l'orientation relative d'un couple de variations de position des points de base. Plus de 100 cas ont été considérés et à chaque fois ont été estimées les précisions des paramètres calculés ainsi que leur correlation. On a de plus, étudié la stabilité de la solution par l'intermédiaire des valeurs propres de la matrice normale.Il n'est pas indispensable, en principe, d'imposer de contraintes précises au choix des points de base; mais de ce choix dépend la fiabilité de la solution, faible s‘il est par trop fantaisiste.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIn der Arbeit wird der Einfluss der Abweichung der gemessenen Punkte von ihrer Standardlage bei relativer Orientierung eines Stereomodells untersucht. Dazu werden mehr als 100 analytische Lösungen analysiert und für jeden Fall die Gewichte der Elemente der relativen Orientierung und die Korrelationskoeffizienten berechnet. Die Stabilität der Lösung wurde durch Berechnung der charakteristischen Wurzeln der Matrix der Normalgleichungen abgeschätzt.Es wird gezeigt, dass theoretisch immer die Lösung des Problems der relativen Orientierung erreicht werden kann, sobald die Lage der Messpunkte die geometrischen Anforderungen erfüllt. Die Zuverlässigkeit der Lösung hängt jedoch von der exakten Lage der Punkte ab. Wenn ihre Genauigkeit zu gering ist, gibt es praktisch keine Lösung.

Notes: Stimulated by promising overseas results with colour aerial photography and encouraged by its potential for solving local problems, the Forests Commission, Victoria, embarked on a series of trials with colour photography in 1965. Early results showed great promise and resulted in further work. This paper describes the methods and results of 70 mm and 35 mm trials concerned with the evaluation of various photographic films. An important aim of the study was to build up a working knowledge of the techniques of using aerial films other than conventional panchromatic black and white and to assess their value under Australian conditions.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Stimulés par les résultats obtenus outre-mer en matière de photo aérienne en couleur, et disposant d'un potentiel adéquat, le Forests Commission, Victoria a entrepris en 1965 une série d'essais, dès le départ très encourageants. On décrit ici les essais d'évaluation de différents types de film (70 mm et 35 mm); le but était de se familiariser avec la couleur et d'en étudier les conditions d'emploi sous les latitudes australiennes.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungAngeregt durch erfolgversprechende Ergebnisse mit Farbluftbildern in Übersee und ermutigt durch die Möglichkeiten zur Lösung lokaler Probleme unternahm die Forstkommission in Viktoria (Australien) eine Reihe von Versuchen mit Farbaufnahmen im Jahre 1965. Diese Versuche erwiesen sich vielversprechend und wurden fortgesetzt. Im Artikel werden die Verfahren und Ergebnisse von Versuchen mit 70 mm und 35 mm Aufnahmen zur Bewertung verschiedener photographischer Materialien beschrieben. Ein wichtiges Ziel der Untersuchung war das Erlangen von Kenntnissen über die Verfahren zur Verwendung nichtkonventioneller panchromatischer Schwarz-Weiss-Filme und deren Bewertung unter australischen Bedingungen.

Notes: A short review is given of photogrammetric methods in use for the test recording of petroglyphs and archaeological sites. Two simple field methods employed by archaeologists to record petroglyphs are also described in order to highlight the complexity of photogrammetric techniques and to query their validity.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméBrève revue de méthodes photogrammétriques en usage pour enregistrer pétroglyphes et sites archéologiques. On décrit en sus deux méthodes employees par les archéologues dont la simplicité contraste avec la complexité des méthodes photogrammétriques.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungKurzer Bericht über die photogrammetrischen Verfahren zur versuchs-weisen Aufzeichnung von Petroglyphen und archäologischen Fundstätten. Zwei von Archäologen zur Aufzeichnung von Petroglyphen verwendete einfache Feldverfahren werden ebenfalls beschrieben, um die Komplexität der photogrammetrischen Methoden zu beleuchten und ihre Richtigkeit zu überprüfen.

Notes: The CP1 plotter has been employed to produce, from low altitude aerial photography, a detailed map at a scale of 1: 1000 of a major landslide which occurred in an urban area of Hong Kong with extreme relief differences. Geomorphological features of the landslide could be interpreted easily from the aerial photographs and shown on the map which provided an accurate record of the disaster. Experiments with computer mapping of the landslide using a limited number of height points obtained by the CP1 plotter have also been carried out and the results indicated that useful data could be obtained rapidly to meet urgent needs for the preliminary stage of investigation and the planning of reconstruction works after the disaster.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméA partir d'une couverture aérienne à faible altitude, on a restitué au CP1 et à l'échelle du 1: 1000 une carte détaillée d'un important glissement de terrain survenu à Hong Kong et présentant d'extrêmes variations de relief. Les caractéristiques géomorphologiques du glissement aisément perçues sur les photos aériennes ont été reportées sur la carte. On a mené d'autre part des essais de cartographie numérique à partir de semis produits par le CP1, qui prouvent qu'on peut ainsi obtenir rapidement des données utiles aux enquêtes et mise sur pied des travaux de reconstruction.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer CP1 Plotter wurde zur Herstellung einer detaillierten Karte im Massstab 1: 1000 nach Luftbildern aus geringer Flughöhe verwendet, um einen grösseren Erdrutsch mit extremen Höhenunterschieden im Stadtgebiet von Honkong zu kartieren. Die geomorphologischen Erscheinungen des Erdrutsches konnten leicht an Hand der Luftbilder interpretiert und auf der Karte dargestellt werden, die eine genaue Aufzeichnung der Katastrophe vermittelte. Es wurden auch Versuche mit einer rechnergesteuerten Kartierung des Erdrutsches mit Hilfe einer begrenzten Menge von Höhenpunkten, die mit dem CP1 Plotter gemessen wurden, durchgeführt. Die Ergebnisse besagten, dass dadurch wichtige Daten schnell ermittelt werden können, um dringende Anforderungen für eine vorläufige Einschätzung sowie die Planung des Wiederauf baus nach dem Unglück zu befriedigen.

Notes: A close range photogrammetric system, developed around a 35 mm Pentax camera fitted with a wide angle lens (f = 21 mm) and an early Zeiss wide angle multiplex, has proved useful for both instruction and research. Student exercises involve all phases of photogrammetry, from establishing ground control to plotting, and permit the integration of useful statistical routines for data analysis. Research applications have centred on the topographic mapping of microscale landforms at scales of 1: 1 to 1: 10 with accuracies of ± 1 mm to ± 5 mm.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméUn système mis au point pour la photogrammétrie à courte distance, et dont les éléments essentiels sont une chambre Pentax (f = 21 mm) et un Zeiss grand angle multiplex, a fait la preuve de son utilité tant pour l'instruction que pour la recherche. Les exercices proposés aux étudiants comportent toutes les phases réelles, depuis l'établissement d'un canevas d'appui jusqu'à la restitution. Les applications à la recherche sont centrées sur la cartographie des microreliefs à des échelles variant de 1: 1 à 1: 10 avec des exactitudes variant de ± 1 mm à± 5 mm.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEin Aufnahme- und Auswertesystem zur Nahphotogrammetrie, bestehend aus einer 35 mm Pentax Kamera, die mit einem Weitwinkelobjektiv (f= 21 mm) ausgerüstet war, und ein alter Weitwinkel-Multiplex von Zeiss haben sich bei der Ausbildung und Forschung als nützlich erwiesen. Bei den studentischen Übungen werden alle Phasen der Auswertung von der Passpunktbestimmung im Gelände bis zur Stereokartierung erfasst, wobei es auch möglich ist, statistische Tests zur Datenanalyse einzubeziehen. Die Forschungsarbeiten konzentrierten sich auf die Herstellung topographischer Karten von kleinmassstäbigen Geländeformen in den Massstäben 1: 1 bis 1: 10 mit Genauigkeiten von ± 1 mm bis ± 5 mm.

Notes: A model of a multiple box girder bridge, constructed at a scale of 1: 12, was subjected to an ultimate load test. Deformations were measured photogrammetrically using the method of false parallax. Modifications to the method are described which were necessary to accommodate the three dimensional object and to allow for the fact that the camera stations were not constant from one load stage photograph to the next. An accuracy of ± 0·2 mm in the measured deformations was achieved.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméUn modèle de boîte de vitesse à l'échelle 1: 12 est soumis à des essais de rupture; on mesure les déformations par photogrammétrie, en utilisant la méthode de la “pseudo-parallaxe”; des modifications ont dûêtre apportées à la méthode pour tenir compte du volume de l'objet et de la variation des points de vue entre les différents états de charge. On a obtenu une exactitude de ± 0·2 mm.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEin Modell einer Hohlkasten-Balkenbrücke im Masstab 1: 12 wurde einem maximalen Belastungstest unterworfen. Die Deformationen wurden dabei photogrammetrisch mit Hilfe von Pseudoparallaxen gemessen. Beschreibung der Veränderungen der Methode, die wagen der Anpassung an das dreidimensionale Objekt notwendig waren und der Tatsache Rechnung trugen, dass die Kammerstandpunkte bei den Belastungen nicht konstant blieben. Die Deformationen konnten mit einer Genauigkeit von ± 0·2 mm bestimmt werden.

Notes: This paper describes the modification, calibration and testing of a non-metric Linhof Technika View camera for use in the stereophotogrammetric mapping and analysis of dental features. The importance of correcting for errors of convergence in very short range stereophotogrammetry is stressed.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit les modification, étalonnage et test d'une chambre non métrique Linhof-Technika en vue de photogrammétrie dentaire; on insiste sur la nécessité qu'il y a de corriger l'erreur de convergence pour de telles études.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung des Umbaus, der Kalibrierung und der Testung einer nichtmetrischen Linhof-Technika-Kamera für die stereophotogrammetrische Kartierung und Analyse von Zahnstrukturen. Betonung der Bedeutung der Korrektur von Konvergenzfehlern bei der Nahphotogrammetrie mit sehr geringen Aufnahmeentfernungen.

Notes: Le microscope électronique à balayage donne l'image de la surface d'un objet situé dans une boîte à spécimen où a été fait le vide. Un fin pinceau d'électrons balaie la surface synchroniquement avec un tube cathodique dont l'intensité est modulée en fonction du signal secondaire émanant du spécimen. Le système présente une grande profondeur de champ; on peut donc obtenir différentes perspectives du spécimen en le photographiant sous diverses inclinaisons (perspectives qui sont centrales, mais cependant justiciables d'être traitées comme parallèles pour de forts grandissements) et donc le restituer spatialement. On donne dans la première partie les limitations pratiques de l'appareillage, ainsi que le type et les causes de distorsion de l'image. Dans la deuxième partie, on décrit les caractéristiques d'un appareil de restitution adaptéà un cas standard: grandissement des deux clichés d'un stéréogramme: fixe-angle d'ouverture du faisceau perspectif négligeable (c'est le cas pour de forte grossissements) et convergence relative des deux positions de la plaque porte-spécimen est fixe.〈section xml:id="abs1-2"〉〈title type="main"〉Zusammenfassung Das Abtast-Elektronen-Mikroskop liefert Bilder der Oberfläche von Objekten, die sich in einer Vakuum-Kammer befinden. Ein feiner Elektronenstrahl tastet die Oberfläche in Synchronisation mit einer Kathodenstrahlröhre ab, deren Lichtpunkthelligkeit von dem sekundären Elektronensignal, das von der Probe ausgeht, moduliert wird. Das System gestattet eine grosse Schärfentiefe und erlaubt dadurch verschiedene Projektionen des zu photo-graphierenden Musters durch Neigung desselben zwischen aufeinanderfolgenden Aufnahmen. Aus der Kenntnis der Geometrie der Projektion (die eine Zentralprojektion ist, jedoch für sehr stark vergrösserte Bilder annähernd als Parallel- oder Orthogonalfall behandelt werden kann) ist es daher möglich, zu dreidimensionalen Analysen durch Messung von Parallaxen zu kommen. Teil I der Arbeit handelt von den praktischen Problemen, die sowohl aus den Grenzen für die mechanische Konstruktion von Muster-Halterungen und Auswertegeräten als auch den Verzerrungen der Bilder resultieren. Teil II beschäftigt sich mit praktischen Gesichtspunkten der bewährten Auswerteinstrumente, die speziell für die Lösung eines standard-isierten Problems der Elektronenmikroskopie konstruiert wurden. Bei diesen wird die Vergrösserung der beiden Halbbilder eines Stereobildpaars konstant gehalten, der Divergenzwinkel der peripheren “Strahlen”, die sich aus dem zentralen “Strahl” ergeben, wird als vernachlässigbar angesehen (was bei Bildern mit starker Vergrösserung der Fall ist) und die Neigungswinkeldifferenz zwischen den zwei Lagen der Probe ist konstant.

Notes: The article describes an experiment in which a production block of aerial triangulation, observed by the method of independent models, was repeatedly computed using differing amounts and configurations of control. The block was recomputed to investigate the effects of control errors, of dispensing with the tie strips and of applying different weights to control and tie points. The connexion between the quality of the join of individual models and that of the adjusted block was also investigated.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit une série d'essais effectués sur un bloc de production de triangulation aérienne analytique traité par la méthode des modèles indépendants, destinés àétudier l'influence du nombre et de la configuration des points du canevas d'appui, l'effet d'erreurs sur les points d'appui, l'effet des bandes transversales, et du choix des poids pour les points d'appui et de liaison. On a aussi examiné la corrélation entre la qualityé de l'enchaînement des modèles individuels et celle du bloc compensé.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines Versuchs, bei dem ein Aerotriangulationsblock aus der Produktion, der nach der Methode der unabhängigen Bildpaare beobachtet worden war, wiederholt bei verschiedenen Anzahlen und Anordnungen von Passpunkten berechnet wurde. Die Berechnungen erfolgten zur Abschätzung der Einflüsse von Passpunktfehlern. Weiter wurde der Anschluss zu Nachbarstreifen und die Anwendung verschiedener Gewichte für Pass- und Verbindungspunkte untersucht. Desgleichen wurde der Zusammenhang zwischen der Qualität des Zusammenschlusses einzelner Modelle und der des ausgeglichenen Blockes untersucht.

Notes: An automatic plotting instrument development is described where the coordinate corrections are introduced in the optical system and not at the photograph. It is suggested that the opto-mechanical devices used for correction and the proposed use of microprocessors for control of these devices offer the possibility of producing a low cost automatic plotter and stereocomparator.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn decrit une solution au probléme de la correction des coordonnées cliché pour le restituteur analytique et le stéréocomparateur: ces corrections sont introduites dans la partie optique du système et commandées par l'intermédiaire de microprocesseurs. Ceci devrait permettre d'abaisser le coût de ce type d'appareil.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines automatischen Auswertegerätes, bei dem die Koordinatenkorrekturen nicht den Bildträgern, sondern dem optischen System zugeführt werden. Es wird angenommen, dass die zur Korrektur verwendeten optisch-mechanischen Vorrichtungen und die vorgeschlagene Verwendung von Mikroprozessoren zu deren Steuerung die Möglichkeit zum Bau eines billigen automatischen Auswertegerätes und Stereokomparators bieten.

Notes: The paper deals with the analytical plotter and its impact on numerical photogrammetry. A short introductory section is followed by examples of the use of a Zeiss (Oberkochen) Planicomp C100 in analytical aerial triangulation, close range photogrammetry and the generation of digital height models. The examples demonstrate the suitability of the analytical plotter for numerical photogrammetry. Computer assistance and computer control allow for advanced data acquisition of high accuracy and speed. In addition, the minicomputer controlling the analytical plotter can be used for subsequent data processing. As a result, projects involving numerical photogrammetry can be carried out entirely in-house, without the need of an external computer.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLe restituteur analytique et la photogrammétrie numérique. On cite des applications du Planicomp C100: aérotriangulation analytique, photogrammétrie à courte distance, constitution de modéles numériques de terrain. Efficacité, rendement, haute exactitude, tels sont les avantages du restituteur analytique. On peut d'autre part bénéficier de l'ordinateur pour toutes sortes de traitements ultérieurs.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer Beitrag beschäftigt sich mit dem Analytischen Plotter (AP) und seiner Auswirkung auf die Numerische Photogrammetrie. Nach einem kurzen Einführungsteil wird über den Einsatz eines Zeiss (Oberkochen) Planicomp C100 in der Analytischen Aerotriangulation, in der Nahbereichsphotogrammetrie und beim A ufbau Digitaler Höhenmodelle berichtet. Die Beispiele veranschaulichen die Eignung des AP für die numerische Photogrammetrie. Einerseits erlauben Rechnerstützung und Rechnersteuerung eine allgemeine, genaue und schnelle Datengewinnung. Darüberhinaus aber ermöglicht der, für die Steuerung des AP verfügbare Minicomputer die rechnerische Weiterverarbeitung der Messdaten. Auf diese Weise können numerisch-photogrammetrische Projekte ohne Einsatz eines externen Computers vollständig bearbeitet werden.

Notes: Book Reviewed in this article:SPHERE, SPHEROID AND PROJECTIONS FOR SURVEYORS. By J. E. Jackson.REMOTE SENSING IN ARCHAEOLOGY, CULTURAL RESOURCES TREATMENT AND ANTHROPOLOGY: THE UNITED STATES OF AMERICA IN 1979. By J. I. Ebert and T. R. Lyons.A HISTORY OF ARCHAEOLOGICAL AIR PHOTOGRAPHY IN GREAT BRITAIN. By R. R. Downey.PROCEEDINGS OF THE INDUSTRIAL AND ENGINEERING SURVEY CONFERENCE, LONDON, 1980. Edited by M. A. R. Cooper.ANALYSIS AND ADJUSTMENT OF SURVEY MEASUREMENTS. By E. M. Mikhail and G. Gracie.A HISTORY OF THE ORDNANCE SURVEY. Edited by W. A. Seymour.IN FOCUS: a rated guide to the best in photographic equipment. By J. Holtz.MAPS AND SURVEYS OF MALAWI. By C. G. C. Martin and other contributors.

Notes: When a member is thought to be domiciled or employed abroad, the name of the country has been added. Errors and omissions should be notified to the Honorary Secretary.

Notes: A brief review of work on airborne metric camera movement has been made. The tolerances for permissible image movement set by various investigators are discussed.The biggest single fault with most metric camera mountings in current use is that the centre of gravity of the camera is well above the line of action of the resilient elastic restoring forces. This results in coupling between the linear vibration of the airframe and the angular motion of the camera. There is a need for a simple device which can be attached to a survey camera in order to record angular motion during actual survey missions.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméAprès une brève revue des travaux concernant les mouvements d'une chambre de prise de vue en vol, on discute les tolérances couramment admises pour ces mouvements.Le défaut de montage le plus fréquemment rencontré, est que le centre de gravité de la chambre est au-dessus de la ligne d'équilibre des forces agissantes.D'où un couplage entre la vibration longitudinale du porte-chambre et le mouvement angulaire de la chambre. Il faudrait créer un dispositif simple permettant d'enregistrer ce mouvement pendant les vols.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs wird ein kurzer Überblick über die Arbeiten zur Bewegung von Luftbildmesskammern gegeben. Die von verschiedenen Autoren für die zulässige Bildwanderung angegebenen Toleranzen werden diskutiert. Der schwerwiegendste Fehler, der am meisten bei den gegenwärtig verwendeten Messkammern auftritt, ist der, dass der Kammerschwerpunkt über der Wirkungslinie der schwingungsdämpfenden Kräfte liegt. Daraus resultiert eine Paarung der linearen Vibration mit der Winkelbewegung der Kammer. Es besteht Bedarf für eine einfache Vorrichtung, die an einer Messkammer befestigt werden kann, um die Winkelbewegungen während des Bildflugs aufzuzeichnen.

Notes: . Micronuclear mitosis in living Spirostomum teres has been studied by sensitive polarization microscopy, and the dynamic aspects of micronuclear division are described. The small, spherical, interphase micronuclei lie in form-fitting depressions in the macronuclear surface. Nuclear division begins with the rounding and slight swelling of the macronucleus and, coincidentally, the micronuclei move out of the depressions and away from the macronucleus, increase in size, and become weakly birefringent. As mitosis proceeds, the micronuclei increase in uniaxial birefringence and elongate to form irregular ovoids that convert to angular structures displaying principal axes of positive birefringence so divergent as to appear oriented at a right angle to one another. Micronuclei maintain this appearance for as long as 60 min and then abruptly change to rectangular-shaped structures, increase in uniaxial birefringence, and begin anaphase elongation. The somewhat dumbbell-shaped micronuclei lengthen at the constant rate of 2.0 μm/min to reach lengths 〉70 μm. It appears that little half-spindle shortening occurs during spindle elongation. Accompanying the changes in micronuclear spindle length are changes in birefringence. Just before elongation begins, presumably metaphase, the micronucleus is uniformly and intensely birefringent. At the magnifications employed, a chromosome plate is not clearly visible as a region of reduced birefringence. As elongation begins, the putative half-spindles are more birefringent than is the interzone, a condition that is maintained until the spindles have achieved ∼30% elongation, at which time a region of increased birefringence develops at the center of the interzone. This pattern persists for a very short time, then gives way to a uniform birefringence of the entire separation spindle that is maintained until elongation is completed. The rate of micronuclear spindle elongation, changes in micronuclear dimensions, and corresponding changes in birefringence are discussed with respect to possible mechanisms of mitosis.

Notes: . Studies performed with the basidiomycete Laccaria trullisata collected from the sandy beach at the Hempstead Lake State Park, Long Island, New York, during the growing seasons of 1979 and 1980, have demonstrated a carposphere (equivalent to rhizosphere) effect. This region exerts a positive influence on the population density of amoebae when numbers are compared with those obtained in the bare sand 5 cm away. Moreover, amoebae have been shown to exist in, and have been recovered from, internal tissue of the cap (72%) and stalk (91%) of these mushrooms. A partial characterization of three strains of amoebae isolated from the internal tissue of L. trullisata and established in clonal culture is presented.

Notes: L'étude, par le protargol, des phénomènes infraciliaires et de leur corrélation avec les phénomènes nucléaires au cours de l'autogamie dans le genre Euplotes montre, par comparaison avec la conjugaison, que les diverses étapes de la morphogenèse sont liées à la progression de l'état nucléaire. Par ailleurs, l'étude comparative des différents types de morphogenèse (bipartition, phénomena sexuel, réorganisation induite par le jeǔne) permet de supposer qu'il existe deux territoires morphogènes soumis à des systèmes de régulation bien distincts. La comparaison des séquences de morphogenèse chez divers hypotriches conduit à dresser un plan général d'évolution de la régulation de l'activité corticale en relation avec l'étendue des remaniements associés à la stomatogenèse.〈section xml:id="abs1-2"〉〈title type="main"〉ABSTRACTThe changes in the arrangement of the infraciliature associated with autogamy in Euplotes are described and compared with similar events associated with conjugation. The successive steps of morphogenesis are strongly correlated with nuclear processes. The comparative study of different types of morphogenesis (binary fission, sexual phenomena, starvation-induced reorganization) leads to the hypothesis that two morphogenetic fields (a ventral one and a dorsal one) depend on separate regulatory systems. From the viewpoint of evolution, the morphogenetic sequences of some hypotrichs have been compared. A general scheme of the evolution of cortical regulation is proposed, taking into account the extension of the area concerned with stomatogenic activity.

Notes: Mouse omentum was studied after intraperitoneal challenge with tachyzoites of Toxoplasma gondii. Parasites inhabit omental histiocytes, fibroblasts, mesothelial cells, and free peritoneal macrophages. Recently infected cells showed enhanced metabolic and functional activity. Villous projections of the parasitophorous vacuole wall appeared, usually opposite the anterior pole of the parasite. In mesothelial cells, projections formed terminal swellings not observed in other infected cells. Activation of host cells was followed by reduction of the density of the cytoplasmic matrix, autophagosome formation, and intracellular edema, indicating the damage. The wall of the parasitophorous vacuole loses the supporting host cell endoplasmic reticulum that was attached to the vacuole just after entrance of the parasite into the cell. Then lysis of the parasitophorous vacuole and complete cell destruction occurs. The growth of parasites in undamaged cells does not coincide with the inflammatory response. Inflammation of the peritoneum develops only after the start of mass destruction of infected cells. Thus tachyzoites of Toxoplasma exert significant pathogenic effects by their ability to activate the host cell, causing lysis of the parasitophorous vacuole and subsequent destruction of the entire cell.

Notes: Discophrya collini is a free-living suctorian with retractile tentacles covered by a thick fibrous cortex. The tentacles contain a microtubular central canal surrounded at the base by a fibrous collar. Electrical stimulation induces a reproducible tentacle retraction. With extracellular electrodes, the tentacles nearest the anode respond initially, contracting by up to 75% of their original length. There is an inverse relationship between voltage level and duration of stimulus in producing a threshold response, and at a set voltage, between duration and degree of retraction. With intracellular electrodes, the membrane potential has been measured as -30 mV, and tentacle retraction occurs in response to as little as 1.25 nA when the intracellular electrode is made the cathode of the circuit. SEM studies show that retracted tentacles have a wrinkled cortex, while TEM shows that the microtubular canal bends as it enters the cytoplasm. No consistent changes occur in the microtubule configuration of the canal on retraction, suggesting that the microtubules are not directly involved in the contractile mechanism.

Notes: A rapid in vitro prescreen for Fe-binding chelators has been developed with growth of Crithidia fasciculata and the sparing of its heme requirement in a defined medium as a test system. The prescreen functions as an index of chelator-mediated Fe transport and as an index of growth inhibition, presumably by the interference with Fe and/or heme metabolism at intracellular chelatable sites. Of 161 chelators examined, 84 were active heme-sparers; 32 of these inhibited growth at low chelator concentrations. Twenty-eight other chelators inhibited growth and another 49 were inactive. Such chelating activity directed at Fe and heme targets in hemoflagellates may provide leads for chemotherapy.

Notes: Study of microorganism growth kinetics requires measurement of maximal specific growth rate. Standard methods of measurement-batch, semicontinuous and continuous steady state-have sources of imprecision that can be substantially reduced by a modification of the continuous steady-state method. Data are presented, using the ciliate Tetrahymena pyriformis, that indicate that the theoretical foundation of the new method is firm and that precision can be increased.

Notes: Viable merozoites of Plasmodium knowlesi were isolated and the proteins that were labeled on intact merozoites by lactoperoxidase-catalyzed radioiodination were identified. Sodium dodecyl sulfate polyacrylamide gel electrophoresis and autoradiography of Triton soluble extracts of labeled merozoites demonstrated eight major bands ranging in apparent molecular weight from 150,000 D to 22,000 D. Exposure of intact merozoites to trypsin (10 μg/ml) for 10 min resulted in the loss of the two highest molecular weight proteins (150,000 D and 105,000 D) and the appearance of two new bands at 70,000 D and 62,000 D. Trypsin treatment under these conditions also removed the receptor(s) for merozoite attachment to erythrocytes. Therefore, these high molecular weight proteins are candidates for the merozoite component that attaches to erythrocytes. There was no evidence that the labeled membrane components were serum or erythrocyte membrane components, two potential contaminants in the preparation. Anti-rhesus erythrocyte antibody did not precipitate labeled merozoite proteins. Furthermore, the immunoprecipitation of labeled merozoite proteins by rhesus anti-merozoite serum was not inhibited by erythrocyte ghosts.

Notes: Species of trypanosomatids without endosymbionts (Leptomonas seymouri, L. collosoma, L. samueli, Crithidia fasciculata, C. luciliae, C. acanthocephali, Herpetomonas megaseliae, H. mariadeanei, H. samuelpessoai, H. muscarum muscarum, Trypanosoma cruzi) and species of trypanosomatids with endosymbionts (Crithidia deanei, C. oncopelti, Blastocrithidia culicis) were comparatively studied by means of electron microscopy. Artificially aposymbiotic strains derived from species with symbiont were also included in the survey. Species with symbiont were found to differ in some ultrastructural aspects from the group of species without symbiont. Paraxial rods of flagella or intraflagellar structure were found exclusively in species without symbiont. Peripheral branching of mitochondria, accompanied by absence of subpellicular microtubules in sites where the mitochondrial branches are appressed to the cell membrane, were found exclusively in species with symbiont. Networks of kinetoplast DNA fibrils were found to be larger and looser in species with symbiont. Symbiont-free strains of species with symbiont retained the same morphological characteristics of their parental species.

Notes: During a freeze-fracture electron microscopical study of the plasma membrane of Tetrahymena, several different types of organized particle assemblies were observed. Three of these were found only on the protoplasmic face and were localized in the anterior-ventral region of the cell. These consisted of plate-like arrays composed of 4–25 triplet rows of small 3–4 nm particles; long, paired linear arrays localized at the tops of cortical ridges and composed of 7–8 nm particles; and elongated tetragonal arrays located in the grooves between ridges and composed of approximately 10 nm particles. The distribution of these arrays is consistent with roles in cellular morphogenesis, chemoreception, or cell-cell pairing during conjugation. In addition, a unique particle track associated with the cytoproct (anal pore) was observed in the external face of the plasma membrane. Furthermore, the protoplasmic face of the plasma membrane is characterized by a high density of particles organized into localized microarrays, consisting of small paracrystals or strings, which exhibit a loose higher-order patterning most evident toward the anterior end of the cell. Particle distributions on the protoplasmic face do not appear to be significantly altered by conditions that cause clumping of alveolar membrane particles. Taken together, these observations are consistent with the idea that the proteins of the plasma membrane are highly ordered and relatively immobile and that the structure of the plasma membrane is regionally differentiated.

Notes: . A new species of Dactylosoma (Dactylosomatidae, Piroplasmia), for which the name Dactylosoma hannesi n. sp. is proposed, was discovered in blood erythrocytes of Mugil cephalus, Liza richardsoni, and L. dumerili (Mugilidae) from Swartkops estuary, located east of Port Elizabeth, South Africa. The life cycle of this species differs in some respects from that described for all other known species of Dactylosoma and Babesiosoma. Mature schizonts contain eight nuclei but undergo division only to two to four daughter cells. During cytoplasmic cleavage, schizonts assume triad, rosette, or cruciform shapes. Merozoites are finally produced through a series of binary fissions of these daughter cells which may also be involved in additional nuclear divisions.

Notes: Electron microscopy was used to examine the flagellar apparatus of Herpetomonas ampelophilae from the gut and malpighian tubules of Drosophila melanogaster. The flagellates attach to the microvilli either by weaving their flagella between the microvilli or by engulfing several microvilli with an external flagellar membrane. The first type predominated in the gut while the second type was limited to the malpighian tubules. Desmosomes were not involved in either type of attachment. A subpellicular collar with emerging microtubules was found to be adjacent to the desmosome of the flagellar pocket of herpetomonads in the gut.

Notes: Prorocentrum micans Ehrenberg, a free-living marine dinoflagellate, was used to test the intracellular toxic action of cadmium. The cells were cultivated in Erdschreiber medium, with Cd concentrations of 10–100 ppb. Thin sections of treated cells, examined ultramicroscopically, exhibited vacuolations, increased numbers of lysosomes, and severe mitochondrial damage. The first two alterations are a general response to toxicity; the third is Cd specific. Although some chloroplasts were affected by Cd, they were not very sensitive to its action. The nuclear apparatus was not morphologically affected.

Notes: Toxoplasma-like avian parasites inhabiting mononuclear phagocytes have been called Haemogregarina, Toxoplasma. avian Toxoplasma, Atoxoplasma, and Lankesterella by various authors. My attempts to transmit the parasites by bloodsucking mites or by transfer of blood and tissues of infected sparrows and canaries were unsuccessful. However, it was noted that the infection was exacerbated under conditions that favored transmission of coccidiosis: crowding and lack of cleanliness. Oral inoculation of sporulated oocysts of Isospora resulted in death from overwhelming macrophage infection with Toxoplasma-like organisms. Experiments using sparrows and canaries showed that the Isospora species involved was not cross infectious. Further investigations using canaries demonstrated that after oral oocyst inoculation, infection of macrophages spread from the submucosa of the duodenum to the liver. spleen, and lungs. After several generations in the internal organs, asexual multiplication, occured in the intestinal epithelium of the small intestinc. Fecal oocysts first appeared at the end of 9–10 days. Oocysts continued to be passed in the feces for months after infection. This chronicity may be explained by the relatively long life of the macrophages that serve as host cells for the asexual stages as compared to the intestinal epithelium which is the cell type parasitized by conventional coccidia.

Notes: Stages of mitosis of the micronuclei of Stentor coeruleus were described as seen by transmission electron microscopy. Cells in division and those regenerating new oral membranelles were studied. Microtubules were found in early prophase in the karyoplasm and interspersed between the condensing chromatin. A monaxial intranuclear spindle is formed by early metaphase, with kinetochore microtubule attachment sites on the chromosomes. The spindle elongates, separating the daughter nuclei at anaphase. A new nuclear envelope, consisting of two unit membranes, begins to form at late anaphase. Small segments of membrane found in the space between the newly forming and the old micronuclear envelopes appear to fuse to form the new nuclear envelope. No ultrastructural differences were found in the mitotic nuclei of cells in division or regeneration.

Notes: SYNOPSIS. The ultrastructure of interphase and mitotic nuclei of the epimastigote form of Trypanosoma cyclops Weinman is described. In the interphase nucleus the nucleolus is located centrally while at the periphery of the nucleus condensed chromatin is in contact with the nuclear envelope. The nucleolus fragments at the onset of mitosis, but granular material of presumptive nucleolar origin is often recognizable in the mitotic nucleus. Peripheral chromatin is in contact with the nuclear envelope throughout mitosis, and it seems reasonable to assume that the nuclear envelope is involved in its segregation to the daughter nuclei. Spindle microtubules extend between the poles of the dividing nucleus and terminate close to the nuclear envelope. The basal body and kinetoplast divide before the onset of mitosis and do not appear to have any morphologic involvement in that process. Spindle pole bodies, kinetochores, and chromosomal microtubules have not been observed.

Notes: SYNOPSIS. Developing 2nd- and 3rd-generation schizonts of Eimeria tenella were found in the ceca of chicks infected orally with sporulated oocysts. Several free 2nd-generation schizonts, which varied in diameter from 11 to 21.6 μm, were found on the epithelial surface of the cecum. Some schizonts appeared to have lost merozoites. Other schizonts were intact, one of which was surrounded by an unbroken membrane that followed the contours of the merozoites. Third-generation schizonts, much smaller than 2nd-generation schizonts and with fewer merozoites, were found only on cut or fractured surfaces of the cecal tissue. Third-generation merozoites appeared shorter and thicker than those of the 2nd-generation and were attached to the schizont residuum. A form with conical protuberances and another with 4 triangular segments were found; they were believed to be developing stages 3rd-generation schizonts.

Notes: SYNOPSIS. Epizootic outbreaks of red-sore disease in several reservoirs in the southeastern United States have been reported to cause heavy mortality among several species of fish having sport and commercial value. The etiologic agent is said to be the peritrich ciliate Epistylis sp.; secondary infection by the gram-negative bacterium Aeromonas hydrophila produces hemorrhagic septicemia which results in death. However, in recent studies on the largemouth bass Micropterus salmoides, Epistylis sp. could be isolated from only 35% of 114 lesions from 114 fish, while A. hydrophila was found in 96% of the same lesions. Transmission and scanning electron microscopy of lesions associated with red-sore disease indicate that neither the stalk nor the attachment structure of Epistylis sp. have organelles capable of producing lytic enzymes. Since other investigators have shown that A. hydrophila produces strong lytic toxins, and in absence of evidence to the contrary, it is concluded that Epistylis sp. is a benign ectocommensal and that A. hydrophila is the primary etiologic agent of red-sore disease.

Notes: Weiser, Jaroslav. 1977. An Atlas of Insect Diseases, 2nd ed. Dr. W. Junk, B. V., Publishers, P. O. Box 3713, The Hague, Holland and Academia Publishing House, Czechoslovak Academy of Sciences, Prague, Czechoslovakia. 81 + 240 pp. 75 Dutch Guilders.

Notes: SYNOPSIS. The structure and cytochemistry of spores of Myxobolus sp. from plasmodia which occur in the gill filaments of the common shiner Notropis cornutus were studied by light microscopy and by scanning and transmission electron microscopy. The thin-walled valves of the pyriform spores are thickened in the lateral sutural and apical regions. Mucous material is associated predominantly with the posterior end of many spores. The plasmodium is surrounded by a syncytial wall bounded by 2 membranes. Pinocytotic channels are formed by the inner membrane and numerous dense vesicles are pinched off at the distal ends of the channels. Sporogenesis is initiated by the envelopment of one vegetative cell by another. The larger, enveloped cell divides to form a disporous pansporoblast, which contains 2 pairs of capsulogenic and valvogenic cells and 2 binucleate sporoplasm cells. Each capsular primordium and connecting external tubule gives rise to a polar capsule which houses a helically coiled polar tubule. The apical end of each polar capsule is plugged by a stopper. The valvogenic cells surround the capsulogenic and posteriorly situated sporoplasm cells to form the spore valves. Iodinophilic (glycogen) inclusions were not seen in spores stained with iodine or Best's carmine. A darkly stained band was observed around the posterior region of most spores stained with Best's carmine. In the electron microscope large aggregates of β glycogen particles were seen in the cytoplasm of sporoplasm cells in mature spores.

Notes: SYNOPSIS. Eighteen strains of algae, including 17 exsymbiotic from Paramecium bursaria, were tested for infectivity for P. bursaria, syngen 2 aposymbiotes, and Concanavalin A (Con A) agglutinability. All 6 infective algal strains were relatively resistant to agglutination by Con A, suggesting that algal surface characteristics are correlated with infectivity. Among the noninfective strains, high and low agglutinability were about equally represented, indicating that the Con A titer alone is not a sufficient indicator of infectivity. It is suggested that noninfective algal strains are the progeny of mutations occurring within the endozoic population and fortuitously selected by the external culture medium.

Notes: SYNOPSIS. Studies on sexual compatibility among populations of different origins of axenically cultivated, heterotrophic, homothallic dinoflagellates resembling Crypthecodinium cohnii have been undertaken using motility mutants and complementation testing. We showed previously that one interbreeding group or biologic species can be found on the East and West coasts of the United States, thus far associated only with Fucus. In addition, we found several strains of these organisms each of which, though fertile in intrastrain crosses, appeared infertile with all other isolates. A continuation of these studies has revealed another biologic species of wide geographic distribution (Taiwan, California, Florida, New York) and apparently associated with sea weeds other than Fucus.

Notes: SYNOPSIS. The effect of pretreatment with Isospora felis and bacillus Calmette-Guérin (BCG) on the reexcretion of Toxoplasma gondii occysts was studied in 16 coccidia-free cats. The following conclusions were drawn: (A) Chronically T. gondii-infected cats reexcreted T. gondii oocysts after superinfection with I. felis, and this reexcretion was prevented in cats infected with I. felis before T. gondii infection. (B) Administration of BCG before Toxoplasma infection had no apparent effect on the outcome of the infection.

Notes: SYNOPSIS Previous surveys of feral Drosophila melanogaster in Clarke County, Georgia, indicated 10 to 30% of the flies were parasitized with Herpetomonas ampelophilae. In the present study, herpetomoniasis in D. melanogaster reared in population cages rose from 0.01% to 90% in 14 days. The infection fluctuated between 5% and 100% during the 250 days in which the ageledeme was maintained. Herpetomonas were found endotrophically, peritrophically, and in the Malpighian tubules. In population cages, although there were sporadic rises in percentages, peritrophic and Malpighian tube infections usually remained low. Endotrophic infections often reached 100%, with individual flies being heavily parasitized. Although Chatton felt that several species of Herpetomonas inhabit a single species of Drosophila, we suggest that all the Herpetomonas in D. melanogaster be referred to as H. ampelophilae.

Notes: SYNOPSIS Experiments were designed to study intestinal pathophysiologic changes associated with coccidial infections in mammalian hosts. Pairs of male Sprague-Dawley rats were killed at various times postinoculation (PI) with 104 or 106 sporulated occysts of Eimeria nieschulzi. The small intestine from each rat was removed, weighed, measured, and divided into thirds. From the middle 11 cm of each third, one cm was fixed for histologic examination. Mucosa was scraped from the remaining 10 cm and was assayed for protein content and for peroxidase, sucrase and trehalase activities. Infection with E. nieschulzi was associated with increased mass of the small bowel. Histologically, crypt depth throughout the small bowel was significantly greater (P≤ 0.005) in infected rats than in non-infected ones on PI days 8 and 16. Villus height did not change drastically during low-dose infections (104 oocysts) and varied during high-dose infections (106 oocysts). As a result of these morphologic changes in the mucosa, crypt/villus ratios were usually significantly greater (P≤ 0.005) in all infected rats throughout the small bowel. In general, increased gut weight and changes in crypt and villus dimensions became evident by PI day 2, were most pronounced at PI day 8, and began to return to control values by PI day 16. Peroxidase, sucrase, and trehalase levels equaled or were slightly higher than in controls on PI day 2, dropped significantly below controls (P≤ 0.05) by PI day 8, and returned to, or exceeded control levels by PI day 16. The intensity of all changes was directly dose-dependent.

Notes: SYNOPSIS Random examination of domestic animals revealed the frequent presence of free-living amebae in their bodies. In diseased or dead cows, dogs, pigs, rabbits, pigeons, and turkeys 15 strains of amebae were found, belonging to the genera Acanthamoeba (A. polyphaga), Hartmannella (H. vermiformis), and Vahlkampfia (V. avara, V. enterica, V. inornata)., They were usually accompanied by other infectious agents in different parts of the host bodies. Pathogenicity of 3 isolates could not be demonstrated by inoculation of laboratory animals.Some features of the isolates differed from those previously known for members of these genera. These strains may be considered amphizoic amebae according to Page (1974).

Notes: SYNOPSIS In a hologamy-like process observed in Oxytricha hymenostoma, 2 cells belonging to complementary mating types fused and appeared to contribute equally to the macronuclei of the organism resulting from the fusion. The process was characterized by the absence of micronuclear division and by fusion of the macronuclei of the 2 partners. True conjugation involving micronuclear meiosis was not observed in O. hymenostoma. The biologic significance and the possible adaptive role of the hologamy-like process are discussed.

Notes: SYNOPSIS The mesenteric microvasculature was studied in rats and rabbits infected with Trypanosoma congolense. By examining vessels in the living animals, trypanosomes were observed to adhere to vessel walls by their anterior ends. It was evident from stained preparations of the vessels that the microcirculation contained 4–1400 times as many trypanosomes as were free in the cardiac blood. Parasites were more numerous in very small vessels than in larger vessels, and they were clustered in groups within the small vessels. The localization of T. congolense in the microvasculature is demonstrated and it is shown that this localization is established by attachment of the organism to the vessel wall.

Notes: SYNOPSIS The quantitative direct fluorescent antibody (QDFA) methods were employed for the antigenic analysis of bloodstream forms and culture procyclics of 2 variants, TRUM (Trypanosome Research University of Massachusetts) 106 and TRUM 107, of Trypanosoma brucei brucei. Intact and trypsinized trypanosomes were studied. It was demonstrated that: (A) The specific variant antigens are localized in the surface coat of bloodstream trypomastigotes. (B) In addition to the common antigens shared by bloodstream forms and culture procyclics, there are also certain antigens unique to these latter stages. (C) Still another group of antigens. not found in the culture procyclics, appears to be shared by the bloodstream forms, irrespective of their variant-specific antigens. These antigens may be present in part in the coat or on the cell membrane and in part within the cytoplasm. (D) Irrespective of the bloodstream-form variant from which they are derived, the procyclics are antigenically the same. The QDFA results are analyzed statistically and discussed in the light of the available literature.

Notes: SYNOPSIS Chemical analysis of axenic cultures of Hymenomonas sp. reveals that the degree of coccolith calcification is inversely proportional to the concentration of available nitrogen sources in the medium. This relationship makes possible a useful degree of control over the organism's calcifying activities. In addition, a possible selective advantage of such a relationship in nature is suggested.

Notes: SYNOPSIS. Fine structure and development of Encephalitozoon cuniculi from rabbits were studied in rabbit choroid plexus (CP) cell cultures and were compared to hamster and mouse microsporida.Sporoplasms had a single limiting membrane and contained a large nucleus. Proliferative forms (schizonts) had double outer membranes, the outermost being associated with the formation of the limiting membrane of vacuoles formed within the host cell cytoplasm. These organisms were often binucleate and divided to form sporonts. Sporonts divided once to form 2 sporoblasts which developed into electron-dense spores. Spores had a thick, 3-layered wall and contained a polar filament.The developmental cycle of E. cuniculi in rabbit CP cultures progressed rapidly. Sporoplasms were observed in host cells at 3 hr postinoculation (PI). By 24 hr PI proliferative forms were associated with host cell cytoplasmic vacuoles which contained developing organisms. Mature spores were present in vacuoles by 2 days PI, indicating that the life cycle in the CP system is ∼ 48 hr.The fine structure and the sequential developmental cycle of the mouse and hamster isolates were observed to be identical to those of the rabbit isolate and different from those of the genus Nosema. It is proposed, therefore, that the 3 organisms represent the same species, Encephalitozoon cuniculi.

Notes: RESUME. Deux espèces d'Enteromonas sont observées, provenant, l'une de l'intestin de Triton, l'autre des crottes du Lapin domestique. La cellule piriforme porte un noyau antérieur et 4 flagelles insérts près du pôle ventral du noyau. Le flagelle récurrent (R) est logé dans une dépression ventrale ou cytostome. Les cinétosomes, disposés en une paire antérieure (#1, #2) et une paire postérieure (#3, R), sont liés entre eux par des microfibrilles. Une fibre microtubulaire située au-dessus du noyau est reliée au cinétosome #1. Une autre fibre microtubulaire sous-nucléaire est homologue de la fibre microtubulaire croisée qui existe chez les cellules de Diplozoaires. Le cytostome est bordé par 2 lèvres: la gauche proéminente et armée par plusieurs rangées de microtubules, la droite contenant seulement une mince fibre microtubulaire associée à des microfibrilles. Le cytostome occupe les 2/3 de la face ventrale. Le flagelle récurrent pénètre dans le cytostome puis dépasse l'extrémite de la cellule. Les Bactéries sont phagocytées au fond du cytostome, entre les 2 lèvres distendues. Elles sont digérées dans les nombreuses vacuoles et les corps résiduels sont évacués par rupture de la membrane cellulaire. L'ergastoplasme est concentré près de la périphérie de la cellule. Il n'y a pas de mitochondrie ni d'appareil de Golgi. Dans les kystes observés la cellule plurinucléée est enfermée dans une enveloppe kystique microfibrillaire, les axonèmes sont libres dans le cytoplasme.Les formes diplomonades sont nombreuses et ressemblent aux cellules d'Hexamita, excepté par le cytostome qui est différent. Dans ces formes, les 2 monades sont souvent disposées selon une symétrie axiale binaire mais quelquefois elles sont associées de façon plus anarchique. La cinétide d'Enteromonas est organisée comme celle d'un zoïde de Diplozoaire. Il est possible que le genre Enteromonas soit à l'origine des Diplomonadida et que l'état diplomonadien transitoire chez Enteromonas se soit stabilisé ensuite chez les Diplomonadida. Enteromonas apparaît plus primitif que les autres genres de Diplomonadida aussi nous proposons de créer 2 sous-ordres: celui des Enteromonadina avec le genre Enteromonas et celui des Diplomonadina avec les genres Trepomonas, Trigonomonas, Hexamita, Spironucleus, Octomitus, Giardia. La disposition des cinétosomes et l'existence du cytostome sont les principaux caractères communs entre Enteromonas et les Retortamonadida, cependant les fibres annexes ne sont pas homologues. Une étude plus complète de la division nucléaire et cellulaire de ces 2 ordres de Zooflagellés est nécessaire pour donner un meilleur schéma évolutif.SYNOPSIS. Fine structure of 2 species of Enteromonas, one from the intestine of the salamander, Triturus vulgaris, and another from the feces of domestic rabbit, Oryctolagus cuniculi, is described. The pyriform cell has an anteriorly located nucleus. The 4 flagella originate from an area near the anterior end of the nucleus. The recurrent flagellum (R) is lodged in a ventral depression or cytostome. The kinetosomes, arranged into 2 pairs, anterior (#1, #2) and posterior (#3, R), are interconnected by microfibrils. One microtubular fiber, connected to kinetosome #1, is situated near the anterior surface of the nucleus. Another, subnuclear, microtubular fiber is homologous to the “crossed'’fiber found in Diplozoa. The cytostome is bordered by 2 lips: the preeminent left lip is equipped with several rows of microtubules, while the right lip contains only a thin microtubular fiber associated with microfibrils. The cytostome occupies 2/3 of the ventral surface. The recurrent flagellum passes over the anterior surface of the cell and then comes to lie in the cytostome. The bacteria are phagocytosed in the bottom part of the cytostome between the 2 distended lips. They are digested in numerous vacuoles. The undigested residual bodies are evacuated by a rupture of the cell membrane. The ergastoplasm is concentrated near the cell periphery. Mitochondria and the Golgi apparatus are absent. In the cyst stage, the multinucleate cell is enclosed in a microfibrillar membrane; the axonemes lie free in the cytoplasm.Diplomonad forms of Enteromonas resembling Hexamita are numerous, except that the cytostome is different in these 2 genera. In such forms, the arrangement of the 2 individuals often has binary axial symmetry, but on occasion they are associated in a more anarchic fashion. The mastigont of Enteromonas is organized like that of a single zooid of a diplozoon. It is possible that the genus Enteromonas is ancestral to Diplomonadida and that the diplomonad state, transitory in Enteromonas, became permanently established in Diplomonadida. Enteromonas appears to be more primitive than the other genera of Diplomonadida. Thus we propose 2 suborders: Enteromonadina, subord. nov. with the genus Enteromonas, and Diplomonadina Wenyon, emend., with the genera Trepomonas, Trigonomonas, Hexamita, Spironucleus, Octomitus, Giardia. The arrangement of the kinetosomes and the existence of a cytostome are the principal characters common to Enteromonas and Retortamonadida, while their “accessory'’fibers are not homologous. A more complete study of division of the 2 zooflagellate orders is necessary for the presentation of a more detailed evolutionary scheme of these groups.

Notes: SYNOPSIS Enhanced esterase C activity could be demonstrated by starch gel electrophoresis in various stocks of Paramecium spp. (P. primaurelia stocks 90 and 540, P. biaurelia stock 93, P. tetraurelia stock 29. P. pentaurelia stock 87, P. octaurelia stocks 31 and 300, and P. multimicronucleatum species 3, stock 8 MO) grown in Adaptation Medium. This esterase, however, was barely detectable when they were cultivated in Axenic Medium. Addition of trypticase to Adaptation Medium resulted in reduction of esterase C in the ciliates. This effect is ascribable to Na acetate present in trypticase. Since esterase C increased with the decrease in acetate concentration (as estimated by gas-liquid chromatography) during growth of Paramecium, acetate appears to be utilized by the cells. Sensitivity of esterase C to acetate occurs in all 6 species of Paramecium examined. Different stocks within a species may have different levels of sensitivity; in one case this is genetically determined. The results emphasize the importance of controlling and manipulating growth conditions for the assessment of inter- and intraspecies variations in the isozymes of Paramecium.

Notes: . Strains of Tetrahymena thermophila were examined in an attempt to establish what role certain ions (Na+, K+, Li+, Ba++, Ca++, Mg++, Mn++, Al+++, Fe+++) play in influencing cell survival time in a culture medium. In short-term experiments (20–30 min), cell survival time in a 1% peptone medium is directly related to the valence of the ion employed. Long-term observations (lasting up to five days) in a 1% peptone medium containing lower ion concentrations revealed that the effects on cell-cycle time are not correlated with the valence state of the ion. Comparisons were made among the ionic resistances of strains of T. thermophila, of T. pyriformis sensu stricto, and of two subspecies of T. pigmentosa. Strains within a species are highly correlated in their patterns of ionic response, while marked differences between species occur. The most distinctive group of strains examined came from one of the subspecies (syngen 6) of T. pigmentosa.

Notes: . A two-stage chemostat modified to accommodate the growth of adhesive organisms was used to determine the yield constant, Y, of a representative soil amoeba, Acanthamoeba polyphaga, utilizing as its prey Pseudomonas paucimobilis. The first stage consisted of a glucose-limited bacterial culture in steady state. The second stage consisted of a simplified predator-prey system, nongrowing bacteria serving as the limiting substrate for amoebae. A refined methodology to more accurately determine Y was developed, and Y for Acanthamoeba polyphaga in batch and continuous culture was determined to be 19.1%.

Notes: . The swiftness of thermotaxis of Paramecium caudatum has been investigated for various populations of organisms by measuring the transient spatial distribution of the gathering process of organisms that are transferred to a temperature-gradient cell from the culture medium. The dispersion obtained from the spatial distribution for each population is found to decrease linearly with time and finally reach a steady state value. The gathering rate determined by the slope of the dispersion strongly depends on population; it increases with population.