ALBERT

Notizen: Underwater photogrammetry is being used in the particularly hostile environment of the North Sea where it has been put into commercially viable operation. The authors discuss underwater photogrammetry related to other means of inspection of oil platforms. They also deal with operational experience of 35 mm and 70 mm cameras, camera calibration, the provision of control and photogrammetric observations and data analysis. The demand for underwater photogrammetry continues to grow.

Notizen: The author reviews the historical background of the analytical orthoprojector and examines the design requirements for this instrument. The construction and performance of the Zeiss (Oberkochen)Z2 orthoprojector are described and an assessment is made of its practical advantages.

Notizen: The new APY (Analytical Photogrammetry Yzerman) system is described and a detailed explanation is given of the principles involved. The APY depends on a unique modular design. A list of the straightforward operations required for its application in data compilation and revision is included.

Notizen: The application of phorogrammetry to the measurement of deformation is discussed and four different approaches are identified and compared. References to and summaries of recent work are made.

Notizen: The development and operation of an inexpensive retractable vertical camera rig is described. Unlike several commercially available camera packages, the cameras on this rig are accesible in flight thus permitting the changing of magazines and other operations. Since the camera carriage is only deployed when over the site to be photographed, the aircraft performance is not degraded during positioning flights.

Notizen: This paper summarises the theoretical and practical development of’an analytical system for close range photogrammetry. The system uses the extended bundle method of phototriangulation and a sophisticated least squares algorithm. A description is given of computer software, and aspects of statistical testing and gross error detection are discussed in order to assess the accuracy potential. Applications of the system, for precise co-ordination of a target range and camera calibration are outlined.

Notizen: A photogrammetric system that is suitable for shallow water detailed mapping at scales from 1:50 to 1:500 for coastal and harbour engineering projects is described. The results from tests using automatic 35 mm Canon cameras on an elevated platform to determine the accuracy of planimetric and depth co-ordinates are presented. The economic benefits of stereophotography through shallow water rather than underwater photography are discussed.

Notizen: This paper reviews the growth in the use of photogrammetric techniques in architecture, principally in the United Kingdom, over the past ten years. The work of the various establishments involved in architectural photogrammetry is described and the results of a questionnaire, distributed within the architectural profession, are analysed. Some comparisons are made with developments elsewhere in Europe.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn examine dans cet article l'extension qu'a connue l'utilisation des méthodes photogrammétriques en architecture au cows des dix dernières années, principalement dans le Royaume-Uni. On y décrit les travaux des divers organismes impliqués dans la photogrammétrie architecturale et l'on y analyse les résultats d'un questionnaire diffusé au sein de la profession liée à l'architecture. On fournit enfin quelques comparaisons avec les développements constatés par ailleurs en Europe.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird über die zunehmende Anwendung photogrammetrischer Verfahren während der letzten 10 Jahre in der Architektur, insbesondere im Vereinigten Königreich, berichtet. Die Arbeit verschiedener Institutionen, die sich mit Architekturphotogrammetrie befassen, wird beschrieben, und es werden die Ergebnisse eines unter Architekten verteilten Fragebogens analysiert. Weiterhin werden Vergleiche zu Entwicklungen in anderen europäischen Ländern gezogen.

Notizen: An individual view is provided of the function of the art and science of photogrammetry, over the whole of the history of attempts to make measurements from optical observations. The predominating influence, in past years, of the need for mapping from air photographs is compared with the prospect that increasing demands for similar facilities in close range measurement, for application in fields such as mechanical engineering, medicine and architecture, may soon be seen to give further encouragement to the development of the subject. The author makes use of illustrations from his experience to point out simple cases where the potential of photogrammetric techniques, in the wider sense, has not been appreciated.

Notizen: The algorithm presented assumes a preliminary determination of the elements of inner orientation and bases its mathematical model on the collinearity condition, from which projective equations are derived. Linearisation of condition equations is based on Taylor's expansion, whilst the subsequent solution follows iteration cycles. The method aims to derive composite corrections to image coordinates, with the aid of test field data.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméL'auteur présente un algorithme oú l'on suppose déterminés au préalable les éléments d'orientation interne. La modélisation mathématique s'appuie sur les conditions de co-linéarité et sur les équations qui en résultent en projection. On linéarise les équations de conditions en utilisant un développement en série de Taylor, et l'on obtient la solution correspondante par itération. La méthode vise à apporter des corrections aux coordonnées images en utilisant les données d'un polygone d'essai.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBei dem dargestellten Algorithmus wird die vorläufige Bestimmung der Elemente der inneren Orientierung angenommen, und das mathematische Modell basiert aufder Kollinearitätsgleichung, woraus perspektive Gleichungen abgeleitet werden. Die Linearisierung der Bedingungsgleichungen erfolgt durch Anwendung der Taylor-Reihe, was für die folgenden Berechnungen einen iterativen Prozess bedingt. Mit der Methode wird angestrebt, Bildkoordinaten mit Hilfe von Testfelddaten zu verbessern.

Notizen: There is a growing interest in the potential of synthetic aperture radar (SAR) for mapping and for gathering intelligence for map revision. This paper first gives a simple guide to the characteristics of SAR and then describes a study carried out to investigate the geometric properties of the imagery and the information content which is of interest for topographic mapping and the production of large scale plans. The conclusions cautiously indicate a potential although better quality images are required and more information must be known about the optimum conditions which should obtain when the data are recorded.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn assiste à un intérét croissant envers le radar à ouverture synthétique (SAR) et ses possibilityés pour la cartographie et pour la collecte de renseignements utiles à la révision. Ce texte commence par donner un simple rappel des caractéristiques de ces radars pour décrire ensuite une étude effectuée sur le contenu informatif et les proprietyés géométriques de l'imagerie radar, qui intèresse la cartographie topographique et la confection de plans à grande échelle.Les conclusions font prudemment état d'une potentialité mais soulignent qu'il faudrait disposer d'images de meilleure qualityé et avoir davantage d'informations sur les conditions optimales à respecter lors de l'enregistrement des données.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs besteht zunehmendes Interesse an den Möglichkeiten von Radaraufnahmen mittels synthetischer Apertur (SAR) zur Kartenherstellung und Erfassung von Daten zur Laufendhaltung. Zunächst wird im Artikel eine einfache Einführung in die SAR-Charakteristika gegeben. Dann erfolgt eine Beschreibung eines Versuches zur Untersuchung der geometrischen Eigenschaften und des Informationsgehalts, der von Interesse für die Herstellung topographischer und grossmassstäbiger Karten ist. Vorsichtige Schlussfolgerungen ergeben Möglichkeiten zur Verwendung solcher Informationen, wobeijedoch eine bessere Bildqualität zu fordern ist. Auch müssen noch mehr Kenntnisse über die optimalen Bedingungen bezüglich der Datenregistrierung bestehen.

Notizen: 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.

Notizen: Landsat multispectral scanner (MSS) and return beam vidicon (RBV) image data in both analogue and digital formats were used to assess the performance of the MSS and RBV sensor systems, and to determine their potential for recording information associated with topographic or land use maps of selected Chinese study areas (Beijing, Tianjin and the Huang He elbow). MSS images permitted the detection of 40 per cent to 50 per cent of the features identified on maps of 1: 250000 scale and larger, whereas the higher resolution Landsat 3 RBV images provided 10 per cent to 20 per cent additional information. Completeness of information extracted from a colour cathode ray tube display exceeded that obtained from analogue single band black and white MSS images by only 5 per cent to 10 per cent. Only through major improvements in spatial resolution will it be possible to compile maps at scales of 1: 250000 and larger from satellite data. Significantly, it appears that instantaneous field of view values of 5 m to 10 m will be required to produce image data of sufficient resolution for topographic mapping or detailed thematic studies of the Asian environment.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé On a utilisé les données de l'imagerie spatiale provenant du scanneur multispectral (MSS) et du tube vidicon à retour de faisceau (RBV) de Landsat, à la fois sous forme analogique et numérique, pour évaluer la performance des systèmes de capteurs MSS et RBV, et pour déterminer leur aptitude à contenir l'information figurant dans les cartes topographiques et les cartes d'occupation du sol, sur des polygones d'essais sélectionnés en Chine (Pekin, Tianjin, et le coude du Huan He). Les images MSS ont permis de détecter 40 à 50 pour cent des détails figurant sur les cartes à une échelle supérieure ou égale à 1: 250000, tandis que les images RBV à meilleure résolution de Landsat C fournissaient 10 à 20 pour cent d'informations supplémentaires. Le volume des informations extraites sur un écran cathodique de visualisation en couleurs n'a dépassé le volume obtenu à partir d'images d'une seule bande MSS en noir et blanc que de 5 à 10 pour cent seulement. Il semble que ce ne soit que par des améliorations importantes dans la résolution spatiale que l'on pourra tirer des données de satellites des cartes à des échelles supérieures ou égales à 1: 250000. Il apparait de manière significative qu'un champ instantané de prise de vues de 5 à 10 m (pixel) sera nécessaire pour obtenir des images ayant une résolution suffisante pour la cartographie topographique ou pour des études thématiques détaillées sur l'environnement asiatique.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Verwendung von Landsat-aufzeichnungen, die mit Hilfe des multispektralen Scanners (MSS) und des Return Beam Vidicon (RBV) aufgenommen wurden und sowohl in analoger als auch digitaler Form vorlagen. um die Leistungsfähigkeit dieser Aufnahmesysteme zu ermitteln und die Möglichkeiten zur Gewinnung von Informationen zur Herstellung von topographischen oder Landnutzungskarten in ausgewählten chinesischen Versuchsgebieten (Beijing, Tianjin undder Huang He Bogen). MSS-Bilder gestatteten die Erkennung von 40 bis 50% der auf Karten im Massstab 1: 250 000 oder grösser identifizierten Objekte, während die RBV-Bilder von Landsat 3, die eine grössere Auflösung hatten, 10 bis 20% zusätzliche Informationen lieferten.Die Vollständigkeit der Information, die von einem Farbdisplay erhalten wurde, überstieg die von analogen einkanaligen schwarzweissen MSS-Bildern erhaltenen nur um 5 bis 10%. Nur durch wesentliche Verbesserungen der Objektauflösung wird es möglich sein, Karten 1: 250000 und grösser nach Satellitendaten herzustellen. Es wird offensichtlich eine Objecktauflösung von 5 bis 10m gefordert, um Bilddaten genügender Auflösung für die Herstellung topographischer Karten oder thematischer Studien des asiatischen Raums zu erzeugen.

Notizen: 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.

Notizen: 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.

Notizen: 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.

Notizen: 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.

Notizen: A method of delineating the extent of floods has been devised involving the establishment of flood surfaces and the creation of photogrammetric digital terrain models. These two data sources are combined in a computer aided map production system and comparisons are drawn between the efficacy of different forms of terrain modelling in a floodplain environment.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn a mis au point, en vue de déterminer l'étendue d'innondations, une méthode numérique combinant les notions de surface innondable et de modèle numérique de terrain (MNT); on se pose le problème du choix du MNT dans un environnement de plaine innondable.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungAngabe eines Verfahrens zur Ableitung der Ausdehnung von Überschwemmungen, wobei die Flut-Oberfläche bestimmt und photogrammetrisch digitale Geländemodelle erzeugt werden. Diese beiden Datenquellen werden in einem rechnergestützten Kartiersystem kombiniert, und es werden Vergleiche bezüglich der Wirksamkeit verschiedener Verfahren der Geländemodellierung in Flussniederungen gezogen.

Notizen: SYNOPSIS. A chemically defined culture medium has been developed for the soil amoeba Hartmannella rhysodes Singh which contains the minimum essential organic requirements for growth. The medium consists of 7 amino acids, 3 vitamins, a carbon source (e.g. glucose) and inorganic salts.

Notizen: SYNOPSIS. A mutant strain of Astasia longa utilized glucose for growth whereas the parent (J) strain did not. The optimal pH for growth of the mutant with glucose (sole carbon source) was near neutrality; the optimal glucose concentration 0.02 M. Cell-free extracts or cell homogenates produced C14O2 when incubated in the presence of C14-labeled glucose. On the other hand, after incubation with C14-labeled glucose, intact parent cells and their respiratory CO2 showed no radioactivity while the mutant-strain cells and CO2 produced were active. Dissimilation of glucose-1-C14 and glucose-6-C14 yielded the same amount of radioactivity in metabolic CO2 in cell-free extracts of both strains. Of five enzymes assayed, hexokinase, phosphoglucomutase, and lactic dehydrogenase were present whereas glucose-6-PO4 dehydrogenase and glucose dehydrogenase were absent in cell homogenates of both strains. Presumably these two strains of A. longa differ in permeability of the plasma membrane. Further tracer and enzyme studies indicated that the Embden-Meyerhof scheme is the principal pathway of glucose catabolism; the hexose mono-phosphate shunt and the direct oxidative pathway were either not operating or quantitatively insignificant.

Notizen: SYNOPSIS. By means of electron microscopy, a study has been made of the fine structure of the macrogametocytes, microgametocytes and oocysts of Eimeria perforans from the intestine of the wild rabbit (Oryctolagus cuniculus). The parasites lie in a vacuole within the host cell. The surface of the gametocytes is not plain, but displays irregular protrusions. A large intranuclear body can be detected within the macrogametocytes. Similar structures are also found within the cytoplasm. Within the latter there exists a large spread out reticulum, the channels and vesicles of which concentrate especially close to the nuclear membrane. Tubuli are seen in the numerous mitochondria, which often have a dumb-bell shape.In most of the gametocytes irregular, strongly osmiophilic lipid inclusions are observed, which always are surrounded by the endoplasmic reticulum. Strange folded ovoid bodies are found within the cytoplasm of the oocysts. Nothing can be told with certainty of their nature and function. Probably they represent specific storage bodies.

Notizen: SYNOPSIS. Tritrichomonas foetus survived much better on extended storage at -95 than at -28d̀C following slow freezing in the presence of 1.0 M glycerol. There was no significant difference between these temperatures in survival up to 8 days, but thereafter the protozoa continued to die off slowly at -28d̀, whereas their numbers remained essentially constant at -95d̀ for 128 to 256 days. The trichomonads' motility was much better after storage at -95d̀ than after storage at -28d̀, and fresh cultures could be initiated from the former much more readily.Other constituents of the suspending medium besides glycerol affect the survival of the protozoa upon freezing. Survival was much better when the protozoa were frozen in the original Diamond's trypticase-yeast extract-maltose-cysteine-ascorbic acid-serum medium in which they had been grown than when they were frozen in physiological salt solution or in fresh Diamond's medium. There was no significant difference between survival in the latter two suspending media. The speed and time of centrifugation needed to remove the trichomonads from the medium in which they had been grown had no effect on their survival upon subsequent freezing. Presumably some product or products of the trichomonads' metabolism have an additional protective action which supplements that of glycerol.When frozen in the original Diamond's medium in which they had been grown plus 1.0 M glycerol, an average of 15% of the trichomonads were alive after 128 days' storage at -28d̀ and an average of 38% were alive at -95d̀C. When frozen in physiological salt solution plus 1.0 M glycerol, these percentages were 8% and 12% respectively.

Notizen: SYNOPSIS. When Spathidium spathula was exposed to X-ray doses ranging from 1–25 kr this animal was found to be more radiosensitive than any ciliate previously reported. A dose of 1 kr is sufficient to increase the time of the first generation from 5 to about 5 1/2 hours. A dose of 4 kr is enough to approximately double the generation time. Bacteria in the medium during irradiation do not protect the ciliate against injury. Animals irradiated as dry cysts are only slightly more resistant than vegetative forms, requiring 10 kr to double the generation time. One day after exposure, irradiated lines are uniformly poor in growth rate (0–2 daily divisions), but later a bimodal response is noticed, some lines remaining poor and others recovering. Within 24 hours after treatment, a number of irradiated animals show structural abnormalities and are greatly increased in size. The experiments have not determined the reason for the high sensitivity of Spathidium but have made certain alternatives unlikely.

Notizen: SYNOPSIS. When Tetrahymena suspended in water were given increasing doses of radiation, oxygen consumption decreased with increasing dose, reaching 60–90% at 600,000 r. Cells irradiated in 0.07 M phosphate buffer, pH 7.4, showed no significant decrease in oxygen consumption even at 600,000 r. The decrease in respiration observed on irradiation of Tetrahymena pyriformis W in water with 300,000 r of X-radiation was prevented by addition of pyruvate or acetate during or immediately after irradiation. Pyruvate stimulated the respiration of the X-irradiated cells, particularly at 10 and 60 min post-irradiation.Lactate markedly stimulated the respiration of control suspensions of Tetrahymena cells and oxidation of lactate by cells irradiated with 300,000 r was increased by 20 to 100%, depending on the concentration of lactate and the time after irradiation. Pyruvate was considerably more effective than lactate in increasing O2 uptake of X-irradiated cells, particularly at 10 min post-irradiation. Thioctic acid affected neither the respiration of control or X-irradiated Tetrahymena nor the oxidation of pyruvate.The growth lag of Tetrahymena increased proportionately with increasing radiation dose; no cells survived 600,000 r. The presence of metabolites during irradiation did not affect the lag period or subsequent growth rates. The effects observed were discussed in terms of an alteration of the permeability of Tetrahymena after irradiation.

Notizen: SYNOPSIS. A full account of the nuclear changes during binary fission and conjugation in a local race of Blepharisma is presented in this paper. The macronucleus consists of 2 nodes connected by a strand. Number of micronuclei varies from 6 to 18. During binary fission, condensation of macronucleus is followed by elongation and thinning of the middle region which finally breaks. Daughter nuclei later attain the typical vegetative form. Notably, during binary fission some micronuclei appear to complete their mitoses by the time the macronucleus attains the condensed form, while others lag behind and exhibit practically every stage of mitosis.During conjugation, from 6 to 10 micronuclei undergo the first pregamic division, the same number through the second division, and two products of the second division take part in the third division. The rest degenerate. Division products of the nuclei in the paraoral region take part in synkaryon formation. The synkaryon undergoes either 2 or 3 divisions. In the former case, of the 4 products, 2 become the macronuclear anlagen, one the micronucleus and the fourth degenerates. In the latter case, of the 8 products, 3 to 4 become the macronuclear anlagen and the rest become micronuclei. Chromatin elimination has been observed during the division of the macronuclear anlage, followed by an extra metagamic fission of the cell.Comparison with two other races from India and an American race indicates considerable diversity in the structure and behaviour of the nuclear apparatus in different races of Blepharisma undulans.

Notizen: SYNOPSIS. Females of Heterakis gallinae were separated on the basis of their capacity to transmit the protozoan parasite Histomonas meleagridis. Sections of worms, capable of transmitting the protozoon, revealed the organism in both males and females as well as in the eggs. Infected male worms contained histomonads in the gut wall and the wall and lumen of the reproductive system. Female worms infected with H. meleagridis showed the organisms throughout the reproductive system. Histomonads, found in uterine eggs possessing shells, had a larger nucleus and reduced cytoplasm.Because of the presence of the protozoon among the sperm in the male reproductive system, it is believed the organism can be transmitted to female worms through copulation. The cycle in the worms also supports the assumption that H. meleagridis was originally a parasite of the worm.

Notizen: SYNOPSIS. Speculations regarding the mode of transmission of monocystid parasites of earthworms over a period of more than 100 years have never been tested experimentally under controlled conditions. In order to do so a stock of infectionfree Eisenia foetida (Sav.) was raised from cocoons and experimental infections were induced in this host using sporocysts of the gregarine parasites Apolocystis elongata Phillips & Mackinnon 1946, and Nematocystis elmassiani (Hesse, 1909). Experimental infections were obtained by feeding to uninfected worms sporocysts obtained directly from infected host worms. This proved that the intervention of a vector is not a necessary condition of infection. Infections could not be induced by injecting sporocysts through the body wall into the body cavity. Infections are thus probably acquired in nature by the ingestion of sporocysts. Sporocysts do not leave the body of the host by being passed from coelom to lumen of the gut, nor do they pass directly to the exterior through apertures of the body wall. There was no evidence of parasitic autotomy. It is therefore concluded that death and decay of the host is the normal method of dissemination of sporocysts. Sporocysts were not infective after drying in air for three weeks. Other sporocysts lost potency after storage in moist conditions for several months. Infections involving the organisms specified were sporadic and unpredictable; modifying factors, such as variations in host susceptibility and latency in infection, appeared to be operating.

Notizen: SYNOPSIS. By an automatic electronic technique—the Flying Spot Particle Resolver—the effect of a wide range of concentrations of vitamin B12 on the size and growth of the B12-dependent Euglena gracilis was studied. Rate of cell growth was directly proportional, and cell size inversely proportional, to B12 concentration. Gross B12 depletion resulted in gigantism and prolongation of generation times.

Notizen: SYNOPSIS. Previously, the reproduction-inhibiting effects of ablastin could only be shown in vivo. The present report describes techniques for the in vitro demonstration and titration of this antibody. With a medium composed of Hanks' balanced salt solution, rat serum, lactalbumin hydrolysate, yeast extract and rat blood lysate, blood stream forms of Trypanosoma lewisi can be grown for approximately 24 hours at 37d̀C. Starting with the medium containing normal rat serum and inoculated with adult (inhibited) trypanosomes from infected rat blood, 50% or more of the parasites are in various stages of division after incubation overnight. Under similar conditions with ablastic rat serum, the parasites do not reproduce but remain as adults. If the medium is inoculated with reproducing trypanosomes from the blood, parasites in the presence of normal serum continue to reproduce, whereas those exposed to ablastin are almost completely converted to adult, non-reproducing forms. Similar results are obtained when the immune sera used are first adsorbed with living parasites to remove all trypanocidal antibodies. Ablastic serum inactivated at 56d̀C for 20 minutes does not lose its inhibitory activity indicating that ablastin is not complement dependent, and parasites grown on media at room temperature are not affected by the antibody suggesting that basic antigenic differences exist between blood stream forms at 37d̀C and culture forms at room temperature. Studies of the conversion of blood stream forms to culture forms indicate that the critical temperature range for the conversion lies between 28d̀ and 30d̀C. The significance of these results is discussed, and possible applications of the techniques described to studies of the mechanism of ablastic action are considered.

Notizen: SYNOPSIS. Normal swimming behavior of Paramecium multimicronucleatum in an essential mineral element solution with 0.0002 M calcium changed into continuous avoidance reactions upon replacement by equimolar strontium; equimolar barium produced a less pronounced similar effect. In equivalent pure SrCl2 and BaCl2 solutions, avoidance reactions were less frequent than in the balanced solutions. P. multimicronucleatum inoculated into autoclaved calcium- or strontium-containing cultures of the alga Protosiphon botryoides (ultimate food source) multiplied greatly and essentially equally, but died in barium. Accelerated avoidance reaction rates were observed in strontium up to and at 32 days after inoculation.

Notizen: SYNOPSIS. A previous study of parasites from relapsed P. berghei infections of mice indicated that the behavior of the relapse parasites differed from that of their parent strain. Experiments have been performed comparing the behavior of relapse and parent parasite infections in mice under two sets of conditions. In one group of experiments the behavior after antimalarial treatments, designed to result in chronic or latent states of infection, was tested. In all, 8 relapse strains were tested against their parent strains in six different experiments which employed 536 mice. It was observed that the mice infected with the relapse strains had a statistically significant greater mortality after the treatments than did mice infected with parent strains. This difference was observed regardless of how the relapse strain had been previously treated, or of what treatment was used in the experiments. In a second group of experiments, the behavior of infections with relapse and parent parasites was compared in normal mice. Five relapse strains were compared to their parent strains in a total of 5 experiments using 356 mice. It was observed that the mean survival time of mice infected with relapse strains was significantly greater than that of mice infected with the parent strains. It is not known whether this apparent difference in the behavior of relapse and parent parasites is related to the mechanism for relapse of P. berghei infections, or is merely a characteristic of parasites that had survived in an immune host.

Notizen: The rate of ingestion of cytoplasm from its prey ciliate by Podophrya collini shows a maximum at 18°C. The rate of ingestion is the same for all active tentacles during the feeding period. Calculation of the amount of cytoplasm ingested from rate measurement and from dimensional alterations of ciliate and suctorian during feeding indicates conformity to the hypothesis that the motive force for ingestion results from integrated activity of the total cell and not from autonomous activity of the tentacles alone. The estimated motive force approximates 0.2 atmosphere. Data is presented to indicate that energy to maintain this motive force is derived from the normal oxidative metabolism of the suctorian.

Notizen: Hepatozoon procyonis, n. sp., is described from the raccoon Procyon lotor from southwestern Georgia. Mature gametocytes in monocytes in blood smears and schizocysts and developing gametocytes in sections of heart tissue were observed and described. A Hepatozoon was also found in the fox squirrel Sciurus niger.

Notizen: In Paramecium there is no known correlation between the direction of electric current through the membrane and of ciliary beat. One reason is that the Ludloff phenomenon, an anodal shift in the limit of the area of reversal with increased current strength, has seemed contradictory to most other data. However, by assuming Paramecium to be a core conductor immersed in a volume conductor and by applying the laws of polarizing currents it is possible to explain all existing data on reversal of normal ciliary action, and also on activation of cilia in immobilized specimens by electrical current. It is assumed that a threshold degree of depolarization of the normal membrane potential or of current density causes reversal. The Ludloff phenomenon is caused by anodal progression of this degree of depolarization with increasing membranecurrent. If it is also assumed that an increase in the membrane potential of immobilized specimens causes activation in the normal direction, one can predict anodal activation, progression of reversal with decrement in velocity, time course of development of excitation, ancdal stimulation upon “break.” stimulation by linearly rising currents, relative refractory and supernormal periods, effect of angle of orientation, and effect of acetylcholine and antiacetylchoiine esterase. Assumption of a neuromotor system is not needed. However, if available data are interpreted in the manner commonly used for nerve it can be concluded that an active accommodative process exists and possibly also a local excitatory state. A recent “dipolar” theory of galvanotaxis is not acceptable because it does not include ciliary reversal.

Notizen: The morphologic phenomena of the conjugation of Paramecium caudatum are analysed by transverse sectioning of couples at the level of the junction zone. This orientation allows exact determination of the adjacent surfaces (which strongly suggests the absence of a paroral cone) and their relation to the ciliary fields. The modifications of the outer pellicle are studied with the electron microscope. It is shown that cytoplasmic communications occur at the top of the ridges which limit the periciliary depressions. The kinetosomes remain apparently intact but cilia and trichocysts disappear. An active role by the latter organelles is suggested for the union of the two conjugants.

Notizen: Resistance to sulfanilamide has persisted in a strain of Chilomonas Paramecium for 255 transfers (63 months) in a drug-free medium. In attempts to modify resistance, stocks derived from sulfonamide-resistant and normal strains have been acclimatized to and then maintained in media containing p-aminobenzoic acid at 5.0, 10.0, 15.0 and 20.0 mgJ100 ml. Each PABA-acclimatized strain was more susceptible to sulfanilamide than its parent stock. In other words, sulfanil-amide-resistant strains lost their resistance and normal strains became hypersensitive. One strain, adapted first to sulfanilamide, subsequently to PABA (15 mgJ100 ml) and again to sulfanilamide, showed a loss of and finally a restoration of sui-fonamide-resistance (but to a degree somewhat lower than the original level).

Notizen: DL-serine, DL-methionine or DL-serine + DL-methionine in excess inhibited the growth of Tetrahymena pyriformis H. Excess serine was most inhibitory at high concentration of folic acid, whereas the effect of excess methionine or methionine + serine was most pronounced at low levels of folic acid. Inhibition due to excess serine was relieved by raising the level of methionine or by adding pyrimethamine to lower the effective folic acid level, and was intensified by adding Dl.-ethionine or by raising the level of folic acid. Similarly, inhibition due to excess methionine was relieved by supplying more serine or adding DL-ethionine (which reduced the amount of available methionine) and was intensified by adding pyrimethamine. Inhibition by excess methionine + serine was reversed by increasing threonine, provided there was ample guanine present. Low levels of guanine or the presence of 8-azaguanine prevented this reversal. Comparisons are made with the work of others.

Notizen: Autogamy in Frontonia leucas is described for the first time. The process appears to occur at irregular intervals. From 7 to 10% of the individuals are affected. The beginning of autogamy is marked by a swelling of all the micronuclei which take part in the first two maturation divisions. The third division however affects only one of the second division products. Occasionally two or three may divide. A paroral cone is not prominent. But a small area close to the peristome is distinguishable as the region where the pronuclei fuse. The syn-karyon divides four times. Some of the division products disintegrate, after which 8 to 9 bodies are left which become differentiated into 4 to 5 macronuclear anlagen and 4 micro-nuclei. Mitotic division of the micronuclei results in their increase in number in the daughter individuals after metagamic divisions. Changes in the macronucleus during autogamy consist in its fragmentation and later absorption in the cytoplasm. There is some indirect evidence of a relationship between the dissolution of the old macronucleus and the development of the new.

Notizen: An electron microscope study of Plasmodium lophurae maintained in vivo and in vitro provided information concerning the sequence of events during reproduction, and the role of the cytoplasm in this process.Contrary to the generally held opinion that nuclear fissions precede cytoplasmic division, it was found that the last nuclear fission takes place during advanced stages of cytoplasmic segmentation. This study also supplied evidence that in addition to repeated nuclear divisions, a number of changes occur in all major components of the cytoplasm. These changes are considered as preparatory for reproduction. The cytoplasm continues to be active during the formation of merozoites. At this stage a segregation of cytoplasmic components takes place resulting in the incorporation into the offspring of a condensed cytoplasm containing all the organelles. The watery part of the cytoplasm with the lipids and food vacuoles is withheld and at the end of reproduction forms the residual body, a separate structure bound by a membrane.

Notizen: Ophryoglena hypertrophica is distinguished by its tomites and its pyriform theronts; by its elliptical and flattened macronucleus with 2 or 3 coupled micronuclei; by its large trophont; by its tomont covered with a thin mucous layer at the interior of which are formed 4 or 8 tomites closely bound one to another. Its physiological evolution is characteristic; the tomite when it comes out of the tomont undergoes a secondary encystment and then becomes the theront. Sometimes the tomite is rostrated and is not attracted by the tissues; the tomite undergoes as before a secondary encystment, but divides inside the cyst. This type also produces complete or partial particular palintomies and regularly forms resistant cysts.

Notizen: Intraspecific chemotaxis between gametes was demonstrated in Chlamydomonas moewusii Gerloff var. rotunda nov. var. which was previously used as C. sp. 24 (Tsubo Y. 1957). a heterothallic isogamous species from Japan. The reaction is unidirectional; the “+” gametes are attracted by the “—” gametes or cell-free supernatant of medium in which the :“-” gametes were suspended. In a study with 4 other isogamous heterothallic Chlamydomonas — C. moewusii Gerloff, C. eugametos Moewus, C. reinhardi Dangeard, and C. morewusii Gerloff var. tenuichloris nov. var. — none of them revealed any intraspecific chemotactic behavior. However, as with the “—” gametes of C. moewusii var. rotunda, both mating types of C. moewusii, C. eugametos, and C. moewusii var. tenuichloris were interspecifically attracted by the supernatant of the “—” culture of C. moewusii var. rotunda. Only C. rein- hardi showed no chemotactic behavior in intra- or interspecific combinations.Although chemotaxis occurred in the above-mentioaed combinations, neither agglutination nor pairing ner zygete formation followed at all in the same combinations. The“;–” cells of C. moewusii var. rotunda killed by osmium vaper and then washed no longer produced the chemotactic agent, but did agglutinate with living “+” cells. Therefore, evidently, chemo-taxis is a separate step from agglutination and zygote-for-mation yet does not seem necessary in the mating of isoga-mous Chlamydomonas. Nonetheless, since this activity appears not in the vegetative but in the gametic stage, it seems to concern the sexual activity of the cells. In preliminary studies the chemotactic agent produced by C. moewusii var. rotunda was shown to be volatile.

Notizen: A microsporidian infection in a laboratory clone of Hydra littoralis has been observed, and the parasite has been tentatively identified as a species of Plistophora. Infected hydra continue to bud and regenerate normally and show no significant physiological or morphological changes. Sexual crossing of infected and non-infected animals shows that the infection is transmitted by the ovum but not by the sperm. Continuous exposure of infected hydra to Fumidil B in solution resulted in the disappearance of all Plistophora spores after a five week period of treatment, and the clones of the treated animals have remained parasite-free for more than a year.

Notizen: Patterns for free and protein amino acids and related substances were determined for Tetrahymena limacis and 7 strains of T. pyriformis from axenic stationary phase cultures grown at 25° C by means of 2-dimensional chromatography in a butanol-acetic acid and phenol solvent system with ninhydrin and other polychromatic indicators. A uniform protein amino acid (PAA) pattern was observed in all strains. There were 14 color spots indicating 19 amino acids (including cysteic acid), identified as follows: alanine, arginine, aspartic acid, cysteine/cystine, cysteic acid, glutamic acid, glycine, leucine/isoleucine/phenylalanine, lysine/histidine, proline, serine, threonine, tyrosine, valine/methionine.The following free amino acids and related substances (FAAs) were identified with 14 spots (several different from these for PAA patterns) found in all strains: alanine, arginine, asparagine, aspartic acid, glutamic acid, glutamine, glycine, leucine/isoleucine/phenylalanine, lysine histidine. proline, serine, threonine, tyrosine, valine/methionine. T. limacis and strains LI and Gf-J of T. pyriformis exhibited these only. Chromatograms of 5 strains of T. pyriformis (PR. F. L3 WH52, HS), however, also contained 1 to 4 spots representing certain of the following substances: Cysteic acid, cysteine/cystine, taurine, and the unknowns X1, X2, and X3, having Rf's of 0.33, 0.79, and 0.72 respectively in 4:1 phenol-H2O system Excepting for F and L3, which were similar, the T. pyriformis strains showed quite different distributional patterns of these substances at 25°C. Other deviations in the distribution of the 6 compounds were noted in the chromatograms of 10° and 35° cultures of WH52 and HS. These findings on FAAs and PAAs are tabulated, along with those of previous investigators, to furnish comparisons on 13 strains of Tetrahymena pyriformis, T. limacis and 9 other species of protozoa.

Notizen: Three new species of Trypanosomatidae were isolated from three species of bugs: Leptomonas leptoglossi from Leptoglossus phyllopus, Crithidia acanthocephali from Acanthocephala femorata, and Blastocrithidia euschisti from Euschistus servus. All were cultured axenically and on avian embryo membranes. In addition to differences in morphology the three organisms displayed different growth rates in the chorio-allantoic fluids of duck and chick embryos incubated at 30°C. L. leptoglossi grew most abundantly. B. euschisti barely maintained itself while C. acanthocephali occupied an intermediate position.When the temperature of incubation was raised to 37°C, there was continued multiplication of L. leptoglossi and C. acanthocephali, but there was no growth of B. euschisti in either duck or chick embryos.It is suggested that the criteria of morphology, cultural characteristics in vitro and in vivo, plus physiological characters be used as future aids in classification of the Trypanosomatidae.

Notizen: SYNOPSIS: Crithidia fasciculata was cultured in a modification of the nutrient medium described by Cowperthwaite in 1951. Carbon dioxide, lactic acid, succinic acid and ethyl alcohol were produced by the organisms during anaerobic conditions. Hexokinase, enolase, alcohol dehydrogenase and glucoses-phosphate dehydrogenase were demonstrated in ho-mogenates of the flagellates. Aldolase, phosphohexokinase and lactic acid dehydrogenase could not be demonstrated.

Notizen: Application of fragmentation and thin-sectioning techniques to Tetrakymena pyriformis, Colpidium compiles and Glaucoma chattoni has permitted an analysis of the ultra-structure of their silverline and fibrillar systems. The classical silverline system consists of a mosaic of flat, membrane-bound blisters whose rims represent the sites of selective silver deposition. Cilia and protrichocysts emerge between adjacent blisters. I The pellicle consists of the membranes outlining the blisters, overlain by a continuous outer membrane that covers the whole cell and cilia. Fibrillar structures, which are not argentophilic, include: (1) tapering, striated kinetodesmal fibers arising singly from the kinetosomes, passing to the right and anteriad, and overlapping to form a loose bundle accompanying each kinety; (2) a longitudinal fibril band immediately beneath the pellicle at the right of each kinety, consisting of overlapping individual fibrils; (3) a transverse band of fibrils arising at the left side of each kinetosome and passing to the left under the pellicle; and (4) a set of postciliary fibrils arising at the right posterior edge of each kinetosome and passing posteriad under the pellicle. The fibrils of sets (2), (3), and (4) all are about 20 Mμ in diameter and appear tubular in cross-section; they are very unlike the heavier, solid kinetodesmal fibers. None of the fibril sets directly interconnect, although transverse and postciliary fibrils end in the vicinity of the longitudinal fibril band.

Notizen: The structure of a cilium in Nyctotherus ovalis is that usually found: two single central filaments surrounded peripherally by nine double filaments; the whole is encased in a ciliary membrane continuous with the pellicle. The two central filaments end in a single enlarged bulb just above a septum, located at about the level of the pellicle, whereas the nine double filaments extend inward to form the cylindrical basal body, which is open at its inner end. Inside the basal body are granules àrranged in rows parallel to its sides. These granules may have significance in the origin of new basal bodies as well as in the outgrowth of new cilia. The latter may have been observed in a few instances. Parallel to the pellicle are two series of fibrils, one median and one inner, connecting adjacent basal bodies. Fibrils extend from the inner end of each basal body, these converge and extend deep into the ectoplasm, often becoming lost in a pattern of equilateral triangles, arranged to form hexagons. These features are clearly seen in the peristomial membranelles, where the basal bodies of the four rows of cilia are close together, separated from adjacent membranelles by a protoplasmic shelf and supported by a mass of fibrillar material comprising the peristomial ectoplasmic band. This broad band extends to the inner end of the peristome whence it returns along the opposite wall as a narrow mass of fibrillar ectoplasm without basal bodies. Peripherally the fibrils are condensed into fan-like bundles; internally they often form a network of equilateral triangles arranged to form hexagons, with corpuscles at the intersections. Trichite-like structures are also found in the peristomial groove and tube; these are connected to both the basal bodies and the fibrillar network.The functions, origin and development of this complex infraciliature during fission constitute one of the yet unsolved morphological problems in such complex ciliates.

Notizen: Sterile Didinium nasutum were fed Paramecium Aurelia which had been grown on monofloral cultures of five different species of bacteria and on a wild mixed culture of bacteria. Didinia grown on monoflorally-fed paramenia or starved paramecia maintained a low daily division rate (0.88-2.06), and after 3 or 4 days died, frequently showing structural abnormalities before death. Didinia fed paramecia grown on a wild mixture of bacteria showed a higher division rate (4.96), did not die after 3 or 4 days, and encysted, when the food was exhausted. It is suggested that a diet consisting of monoflorally-fed or starved paramecia is inadequate for Didinium. This may be due to the lack of some substance or substances related to the enzyme system of the predator, possibly proteolytic enzymes elaborated by paramecia. In the experiments of Gause on the destruction of one species by another, his failure to establish population oscillations between Didinium and Paramecium might have been due to an inadequate diet for the didinia which resulted in their lack, of encystment and death.

Notizen: The exoerythrocytic forms of Plasmodium gallinaceum in thin sections of infected tissue cultures have been examined with the electron microscope. It was seen that important changes occur in the fine structure of the parasite during the various phases of the cycle. The cytoplasm of the merozoites at the beginning and at the end of each cycle shows a great electron density due to a fine granulation. Larger granules are found at one pole of the parasite. The merozoites have a large nucleus in the center, and an oval body of great electron density at one pole, the significance of which is unknown. Short canaliculi can also be seen in the cytoplasm, but no mitochondria have been found.The cytoplasm of the schizonts shows a low electron density. It contains small particles scattered irregularly throughout its whole mass. The nuclei are not well defined; the oval body observed in the merozoites apparently has disappeared. Short canaliculi are present everywhere; however, mitochondria could not be identified with certainty.In the final phase of the cycle, in the rosette formations, the cytoplasm assumes again the fine granular structure. The future merozoites are grouped around a cytoplasmic core, with which they are directly connected. The whole segmenter is situated in a vacuole formation. In cross sections of the merozoites an opening in the central pole has been observed.

Notizen: An account of conjugation in an American species of Blepharisma is given. A comparison is also made with the available knowledge of the two Indian species of this genus. In the conjugating pair, the condensed macronucleus shows Feulgen negative regions. Before the conjugants separate, the macronuclear and micronuclear anlagen become distinguishable.The species is characterized by a number of striking features which become noticeable after syngamy. The synkaryon divides thrice giving rise to 8 bodies. Of these, 3 to 7 become the macronuclear anlagen and the rest, the micronuclei. The resorption of the old macronucleus occurs much later, just before the exconjugant attains the vegetative form. No metagamic fissions occur in this species and each exconjugant becomes a vegetative animal in 5 or 6 days. During this period, the macronuclear anlagen arrange themselves in a series and develop slender connections with one another to produce the moniliform macronucleus of the vegetative animal. The micronuclear anlagen, on the other hand, divide by mitosis to attain the vegetative number. In this species 40% to 45% of the exconjugants are viable and the rest die.

Notizen: Seven species of astomatous Infusoria from the alimentary tract of the Oligochaeta from Ochrida Lake are described. One of them, belonging to Hoplitophrya, shows many transitional characteristics between Juxtaradiophrya and Hoplitophrya and proves the coherence of the group Radio-phryinae-Hoplitophryinae-Mesnilellinae. Two species are Maupasellinae, parasites from Glossoscolecidae. Buchneriella and Maupasella, both parasites from Criodrilus lacuum, a cosmo politan worm, are also present in C. ohridensis, endemic species coexistent with the preceding, at Ohrid. Two other sro belong to Intoshellina. A discussion about the actual systematic state of Intoshellinidae is given, affinities of this family remaining uncertain. The two last species described are a typical Anoplophrya and a representative cf a new genus Corlissiella, having many morphological and biological similarities to the primitive thigmotrichs. Heterogeneity of the Anoplophryidae is discussed.

Notizen: A small reversible A.C. motor is utilized in the construction of a device to tighten and loosen the caps of screw-cap test tubes.

Notizen: A new species of Coccidia, Eimeria neosciuri sp. now, has been described from the squirrel host, Sciurns (Neo-sciurus) carolinensis. The oocysts (21.8-28.0 ju X 13.7-18.1) are elliptical in shape without a visible micropyle. The sporo- cysts are oval with protruding nipple. The endogenous stase; of this species occur in the epithelial cells of the villi of the upper ileum. Oocyst production declines in about a fortnight after a rise to its maximum during the first 6-10 days.

Notizen: Ergosterol was isolated from the non-saponifiable lipids of Euglena. For this, after saponification of the cells, the petroleum-ether extract was chromatographed on deactivated alumina. Development was achieved by pet. ether and 10% (v/v) benzene in pet. ether, and the sterol fraction was subsequently eluted with 10% (v/v) ethyl acetate in pet. ether. This sterol was identified as ergosterol by a) precipitation with digitonin, b) The Liebermann-Burchard reaction, c) co-chromatography with known ergosterol, d) ultraviolet absorption spectrum, e) conversion to the acetate with determination of the melting and mixed melting points and !” infra-red absorption spectrum of the acetate derivative. By these techniques, ergosterol content was measured in the-following strains of Euglena gracilis under various conditions of nutrition and illumination: bacillaris and Z strains, and several albino and pigment mutants derived from them. A. functional chloroplast seems unnecessary for ergosterol synthesis; the ergosterol content of cells (dry weight basis) was constant regardless of strain and growth conditions.

Notizen: The structure of the excretory apparatus of Paramecium caudatum and P. aurelia was studied in electro-micrographs of ultrathin sections. The so-called nephridial plasma visible in light microscopy was revealed as a network of fine branching tubules (nephridial tubules), of average diameter about 200 Å, which surround the nephridial canals. The nephridial tubules are connected peripherally directly to branches of the endoplasmic reticulum, which extends throughout the organism. During diastole of the radial canals the nephridial tubules open into the nephridial canals, but this connection is broken during systole. Surrounding the nephridial plasma are bundles of larger tubular elements (about 500 Å diameter).The osmiophile wall of the terminal nephridial canal continues without change in the walls of the ampulla, the injection canal and the contractile vacuole. Contractile fibrillar elements, arranged in fiat band-like bundles and of tubular structure (about 150-250 A diameter) without periodic cross-striations, begin at the top of the ampulla and extend, along the surface facing the pellicle, over the injection canal and contractile vacuole to the excretory canal, which they surround as a spiral envelope.The closing of the contractile vacuole to the excretory canal is effected by a relatively compact membrane without pores, so that the emptying of the vacuole must follow breaking of this membrane. The function of the excretory system is discussed in the light of these new observations.

Notizen: Nucleic acid, the nitrogen content per cell, and cell and nuclear volume were determined in 4 green and 2 heat-induced colorless strains of Euglena gracilis and one strain of Astasia longa. All strains of Euglena were identical in cell and nuclear volume. The deoxyribonucleic acid content per cell of the apoplastidic strains was higher than that of the corresponding green strains by I1/, times. Although their nuclei were not enlarged, Feulgen staining of the colorless strains was also more intense. The significance of the increase in DNA in experimentally induced apoplastidy is discussed. As for N total nucleic acid P, and pentosenucleic acid—the dir between the strains reflected previously established morphological and physiological relationships between them. The single strain of Astasia studied was identical in stru: and size with the apoplastidic Euglena stnMH Hownner. it was quite unlike them in all the biochemical characteristic; examined.

Notizen: . Norlevinea n. g. is established for microsporidia in which a uninucleate meront changes into a sporont by secreting a thin, membranous, sporontogcnetic and fragile sporophorous vesicle (pansporoblast membrane) in which four uninucleate sporoblasts are formed. In contrast to the genus Gurleya, the sporoblasts and later the spores are permanently joined into doublets, being laterally cemented by an electron-dense substance structurally identical to and continuous with the exospore layer. The polar filament is of the anisofilar type. The type species is Norlevinea daphniae (Weiser, 1947) n. comb., a parasite of the ovaries of Daphnia longispina occurring in several carp ponds in Czechoslovakia.

Notizen: . The microsporidian parasite known as Nosema helminthorum Moniez, 1887, parasitic in the tapeworm Moniezia expansa (Rudolphi, 1810), has been shown by electron microscopy to have two cycles of development, one with isolated nuclei, the other with paired nuclei (diplokarya). Both merogony and sporogony of the two separate sequences take place in direct contact with the host cell cytoplasm and ultimately give rise to unikaryotic and diplokaryotic sporoblasts. Sporogony is disporoblastic. The nuclear condition of the spores was not seen. The sequences, corresponding to those of the genera Unikaryon and Nosema, may be part of a single dimorphic life cycle and, if so, the species will have to be transferred to a new genus.

Notizen: . Sarcocystis falcatula Stiles, 1893 is re-described. Intermediate hosts of the parasite which was earlier described as Sarcocystis debonei Vogelsang, 1929 are species of passeriform, psittaciform, and columbiform birds. In these birds, muscle zoites are 6.88 × 2.19 (4.8-8.4 × 1.2-3.6) μm and are enclosed in a cyst wall with regular protrusions, 1-5 μm long. The convoluted primary wall has multiple thin areas in the osmiophilic layer. Microtubules originate in the ground substance and extend to the tips of the protrusions. The only known definitive host is the opossum, Didelphis virginiana; rats, cats, a dog, and a ferret could not be infected from muscle cysts. Sporocysts from opossums infected from five different infected avian sources measure 11.2 × 7.4 (9.6−12.0 × 6.0-8.4)μm.

Notizen: . Descriptions are given of two new species of Hepatozoon Miller, 1908 found in the pygmy squirrel, Idiurus macrotis, in the Ivory Coast. Gamonts of both are parasites of monocytes.The size and shape of the gamonts of one, H. normani n. sp., are similar to those of a number of gamonts of other species of rodent hemogregarines and the separate identity of the parasite is based on the host restriction of mammalian hemogregarines. The gamonts of the other species, H. dolichomorphon n. sp., are remarkably long and slender and are unlike those of any other known hemogregarine of mammals. Schizonts of this species were found in a smear prepared from heart blood.

Notizen: . The presence of nonvariant antigens (NVAs) limited to bloodstream forms of Trypanosoma brucei brucei and Trypanosoma brucei rhodesiense was demonstrated for the first time by immunodiffusion and Immunoelectrophoresis. Noncloned and cloned populations were employed in preparation of polyclonal antisera in rabbits and of antigens to be used in the immunologic reactions. The NVAs could be shown best in systems in which hyperimmune rabbit sera (adsorbed with procyclic forms to eliminate antibodies against antigens common to bloodstream form and procyclic stages) were reacted with trypanosomes characterized by heterologous variant-specific antigens (VSAs).The NVAs demonstrated in this study are very likely different from the common parts of VSAs. As has been suggested by experiments with living trypanosomes, at least a part of the NVAs appears to be located on the surface of the bloodstream forms. In these experiments involving the quantitative indirect fluorescent antibody test, the amount of fluorescence recorded for the heterologous system, i.e. ETat 5 trypanosomes incubated with anti-AmTat 1.1 serum, equalled ∼3.0% of the fluorescence emitted by the AmTat 1.1 bloodstream forms treated with their homologous antiserum. Evidently, only small amounts of NVAs are present on the surfaces of T. brucei bloodstream forms.In addition to the NVAs, the electrophoresis results suggested the presence of antigenic differences between procyclic stages belonging to different T. brucei stocks.

Notizen: . Late schizonts from continuous cultures of P. falciparum were concentrated over Percoll, inoculated to various experimental media at the rate of about 20 × 106 per 0.5 ml of medium, and incubated in a candle jar at 37° for 1 day. Controls in standard culture medium showed a heavy invasion with young rings in the previously uninfected red cells introduced with the inoculum of schizonts. In a medium of high potassium content containing a 33% extract of human erythrocytes, this invasion was inhibited and many free merozoites were present. If, however, this same medium was supplemented with both ATP, as the dipotassium salt at 1.6 mM, and sodium pyruvate at 3.6 mM, there appeared large numbers of extracellular forms resembling young rings. Examination of these by electron microscopy shows that they are indeed merozoites that have begun to differentiate extracellularly. This suggests that the trigger for differentiation of merozoites may not depend on the process of entry into a red cell but rather on specific factors within the red cell.

Notizen: . Opossums (Didelphis marsupialis), act as intermediate hosts for Besnoitia darlingi and could be infected orally with sporozoites (oocysts) and bradyzoites (tissue cysts), or intraperitoneally (i.p.) with tachyzoites. Infections could presumably be transmitted through cannibalism. Cats (Felis catus), the definitive host, could be infected only with bradyzoites but not sporozoites. Oocysts shed by cats measure about 12 × 12 μm, resemble similarly sized oocysts of Toxoplasma gondii and Hammondia hammondi, and must be differentiated by the appearance of tissue cysts after experimental infection of intermediate hosts. Cats did not form tissue cysts of B. darlingi. Tachyzoites from the related B. jellisoni could be used in the Sabin-Feldman dye test to determine the development of antibody to B. darlingi in opossums after infection.

Notizen: Developmental stages of Caryospora simplex were found in connective tissue of the cheek, tongue, and nose of Swiss-Webster and C57 BL/6 mice (Mus musculus) from 8 through 70 days after oral inoculation with 50,000 or 250,000 oocysts, or 60,000 free sporocysts of the same species obtained from an Ottoman viper, Vipera xanthina xanthina. The earliest developmental stages were seen on day 8 post-inoculation (PI) and consisted of two types of meronts and gamonts (undifferentiated sexual stages). Gamonts, microgametocytes, macrogametes, and unsporulated oocysts were found on days 10 and 12 PI. Fully sporulated, thin-walled oocysts containing eight sporozoites surrounded by a thin sporocyst membrane were first seen 12 days PI. Monozoic cysts (caryocysts) were first seen 12 days PI and appeared fully viable throughout the duration of the study, 70 days PI. Four mice injected intra-peritoneally with 150,000 free sporozoites and killed 12 days PI contained unsporulated and sporulated oocysts in connective tissues of the cheek, tongue, and nose, suggesting that sporozoites may be carried to the site of infection via the lymphatic/circulatory system. Four cotton rats, Sigmodon hispidus, inoculated orally with 250,000 oocysts all had unsporulated and sporulated oocysts of C. simplex in connective tissue of the cheek, tongue, and nose when killed on day 12 PI, indicating extraintestinal development in the secondary host is not species specific. This is the first report of a heteroxenous coccidium with both asexual and sexual development in the primary (predator) and secondary (prey) hosts.

Notizen: Trypanosoma lucknowi n. sp. was isolated in culture from one of 126 Macaca mulatta originating from the vicinity of Lucknow, Uttar Pradesh, India. Trypanosoma lucknowi is distinctive because of the large number of epimastigotes and trypomastigotes which, in culture, exhibit no movement or only a slight bending of the flagellar end. This limited motility coincides with a free flagellum which is either completely absent or rudimentary. The microorganism is cloned readily, and the description is based upon such cultures. Trypanosoma lucknowi shows pronounced differences from other trypanosomes of South Asian macaques and from “aflagellar” African trypanosomes. The ultrastructural demonstration of a cytostome and contractile vacuole suggests ultimate grouping with stercorarian trypanosomes. A 3-D reconstruction of the flagellar pocket/cytostome region is included.

Notizen: The ultrastructure of the freshwater, heterotrophic dinoflagellate Peridiniopsis berolinense (Lemm.) Bourrelly resembles other dinoflagellates in the structure of its nucleus, theca, flagella, and mitochondria. Other features less frequently reported in related organisms include fine sub-sulcal fibers, collared pits in the flagellar base region, and unusual structures herein termed fibrillar lamellae. Numerous vesicles are present, some of whose contents are distinctly crystalline, while others contain what appears to be membranous material arranged in either whorls or parallel stacks; still other vesicles contain electron-dense, granular spheres. Of particular interest is the transitional helix present in the longitudinal flagellum, this being the first report of such a structure among the dinoflagellates. Plastids of any kind are lacking, and a peduncle is present and is used during phagotrophy.

Notizen: Several axenic strains of pathogenic and nonpathogenic Entamoeba histolytica were tested for their capacity to digest native radioactive type I collagen gels and to produce liver abscesses when injected into the liver of newborn hamsters. The results demonstrate that the pathogenic strains of amebas (HM1:IMSS, HM3:IMSS, HM38:IMSS, and HK9) have a collagenolytic activity that closely correlates with their in vivo capacity to produce liver lesions. The nonpathogenic isolate (Laredo) did not show collagenolytic activity and failed to produce lesions in the liver of newborn hamsters. The results also demonstrate that type I collagen obtained from rodents and cats is degraded less by amebic collagenase than is bovine collagen, which is similar to human collagen. These findings suggest that species susceptibility to invasive infection may depend, among other factors, on the characteristics of the extracellular components of host tissues.

Notizen: At Makthlawaiya, in the Paraguayan Chaco, the prevalence of Trypanosoma (Schizotrypanum) cruzi infection among both domestic Triatoma infestans and domestic dogs was 38%, and IgG anti-T. cruzi antibody was detected by the quantitative enzyme-linked immunosorbent assay (ELISA) in 80% (105/133) of human sera. Ninety percent (25/28) of T. cruzi strains isolated from both T. infestans and dogs showed heterozygous isoenzyme profiles for glucose phosphate isomerase, phosphoglucomutase and 6-phosphogluconate dehydrogenase. These strains appeared to be closely related to Bolivian zymodeme 2. Three Paraguayan T. cruzi strains showed homozygous isoenzyme profiles, similar to those of major Brazilian zymodemes. It was concluded that T. cruzi strains with heterozygous isoenzyme profiles predominate in domestic transmission cycles in this highly endemic area of the Paraguayan Chaco.