ALBERT

Notes: 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.

Notes: SYNOPSIS. When two strains cf T. pyriformis that do not require exogenous pyridoxine are crossed, all progeny grow without the vitamin. Offspring from crosses of two pyridoxine requiring clones require pyridoxine with the exception of a few which will grow without pyridoxine. The ratio is approximately 3:1 favoring the pyridoxine requiring category. In matings involving the homozygous dominant pyridoxine requiring clones with the double recessive mutant, that is +/+ X p/p, all of the resulting progeny need pyridoxine. Test crossing these heterozygotes (+/p) with the parental pyridoxine non-requiring clones (p/p) gives offspring approximating a 1:1 ratio. Matings between two heterozygotes derived from breeding experiments also yield progeny in approximately 3 pyridoxine requiring: 1 pyridoxine non-requiring. All data indicate selection for the heterozygote in the population and a possible selection against either homozygote. The great abundance of heterozygotes and rarity of recessive homozygotes in natural habitats corroborates these findings. The genetic evidence supports a single gene hypothesis although the possibility of multiple closely linked genes cannot be ignored. There is also the possibility that a dominant suppressor gene may function in blocking the activity of the pyridoxine mutant genes. Moreover, if this gene exists it may be incompletely dominant since the heterozygote grows slightly on deficient media.

Notes: SYNOPSIS. Trichodina urinicola was found in newts, Triturus cristatus and T. taeniatus, in three localities in Czechoslovakia. The ciliate populations showed important differences on the basis of which they were separated as three new forms of this species: T. urinicola f. typica, T. urinicola f. bohemica, both from Triturus cristatus, and T. urinicola f. taeniatus from Triturus taeniatus. The great variability of trichodinids is evident from the literature as well as from our own observations, so that these new forms are to be regarded as provisional ones until it is possible to decide on the basis of a large number of observations the extent of specificity and variation of individual endozoic species of Trichodina. A detailed description of these forms is given as well as a comparison with the known species of trichodinids inhabiting the urinary tract of amphibians. A brief comment on the present taxonomy of the Urceolaridae in general is outlined.The need for a uniform description of these ciliates is emphasized; in connection with this, the taxonomic value of individual body characters is discussed. Special attention is paid to the adhesive disk of Trichodina, the structure of which is of greatest importance in the taxonomy of this group. On the basis of Dogel's and Fauré-Fremiet's descriptive methods employed in study of trichodinids, a proposal of a uniform description of Trichodina is made which involves all the important features of these protozoa.

Notes: SYNOPSIS. Several substrains of Euglena gracilis var. bacillaris made chlorotic by treatment with pyribenzamine or streptomycin, or by growth at high temperature (35–36°C.), have been examined for their carotenoid content. They differ from the normal green strain both qualitatively and quantitatively. Some strains produce no detectable carotenoids while the carotenoid concentration in the strains producing most is at best only one-fifth that of the normal strain. In all substrains producing carotenoids, the carotene fraction consists of β-carotene accompanied by some members of the phytofluene series. In only two of these substrains, HB-G and PBZ-G3, are xanthophylls produced in significant amounts. In HB-G, the main pigment is echinenone, and in PBZ-G3 it is zeaxanthin. The significance of these findings is briefly discussed.

Notes: SYNOPSIS. Association of gamonts of Pyxinia crystalligera takes place in the midgut of its beetle host, Dermestes vulpinus. At 25°C. the development of gametocysts to the point of liberation of sporocysts is completed between about 15 hours and 27 hours after the gametocysts are deposited with fecal material. Dehiscence is favored by relative humidities of 0% to 90%, but is not favored by a relative humidity of 100%. During the early development of the gametocysts outside the host, the crystals and paraglycogen granules in the cytoplasm of the associated gamonts become concentrated in large masses. The gametes are formed at the periphery of the gamonts. After fusion of the gametes takes place and the sporoblasts begin to develop, the residual cytoplasm containing the inclusions moves outward to form a continuous layer next to the gametocyst envelope, so that the sporoblasts become crowded into a central core. A few hours before dehiscence is initiated a clear area appears on the upper side of the gametocyst. The contents of the gametocyst begin to shrink away from the envelope except in the region of the clear area. Eventually the sporocysts emerge through the clear area and press against the envelope of the gametocyst, causing formation of a conical papilla in the envelope. With continued pressure from the sporocysts, the papilla ruptures at its tip, and the sporocysts emerge in a continuous thread until dehiscence is completed. The thread of sporocysts may attain a length of about 11 mm.

Notes: SYNOPSIS. The steps leading to purine ring closure were examined in Strigomonas oncopelti. The flagellate has an obligate adenine requirement (hypoxanthine and guanine are inert) when grown without p-aminobenzoic acid. The imidazole counterpart of adenine but not the imidazole counterpart of hypoxanthine was active. A pathway for purine biosynthesis compatible with these results is sketched.

Notes: SYNOPSIS. The Nuttallia of the gerbil is transmitted by Rhipicephalus secundus only if the infected meal is taken by the larva, and the subsequent nymphal stage is the only one which is able to infect. There is no transovarial transmission.Infective trophozoites remain in the larval caeca for about 12 hours after gorging. The infective nymph is able to give rise to new infections at various times after it has been allowed to feed, but never later than the third day after disengagement from the host.

Notes: SYNOPSIS. The process of autogamy in unassociated individuals of Paramecium polycaryum was reported by the author in 1954. In May, 1955, conjugation was first seen in this species in cultures collected by me at Annamalainagar, South India, thus removing it from the list of non-conjugating species. This appears to be the first instance in which the process of autogamy was detected prior to observation of conjugation in the same species. Autogamy occurs in singles of the Indian race and appears to be similar, cytologically, to that of American races. The details of the micronuclear behavior in conjugation parallel those of autogamy in singles. In fact, the conjugation process seems to be one of double autogamy (cytogamy), rather than of reciprocal gametic interchange. Paroral cones, often of fair size, are formed but breakdown of the cones to permit micronuclear passage has not been observed. In conjugation there are the usual three pregamic divisions; the first shows four characteristic crescents. The resulting nuclei may all participate in the second division. Fertilization occurs in the paroral cone area. Frequently, separation of the conjugants takes place immediately after the first division of the synkaryon. The old macronucleus undergoes very little change prior to the last postzygotic micronuclear division in the ex-conjugant, when it goes into a skein condition. Four macronuclear and four micronuclear anlagen are formed in the ex-conjugants at the completion of reorganization. On occasion giant individuals of P. polycaryum were observed to have ingested numbers of Tetrahymena pyriformis. The presence of an unidentified rod-like organism in the cytoplasm of the paramecia (non-conjugating) was detected in one collection from Bangalore, India.

Notes: SYNOPSIS. Thymidylate synthetase (E.C.2.1.1.45) has been demonstrated in unsporulated oocysts of Eimeria tenella. The properties of this enzyme have also been investigated in Tetrahymena pyriformis, as a protozoan model, and 7-day-old chick embryo, as a host model. The enzymes from E. tenella and chick embryo were inhibited by all concentrations of MnCl2 and MgCl2 tested. Tetrahymena pyriformis thymidylate synthetase was stimulated by low concentrations of both these cations but was inhibited by high concentrations. Subsequent data refer to chick embryo, E. tenella and T. pyriformis respectively: the apparent Km was 5.89 μM, 5.94 μM, and 0.53 M for the substrate dUMP: and 5.13 μM, 1.10 μM and 4.65 μM, respectively for the cofactor N5N10-methylenetetrahydrofolate. The pH optimum for the enzyme from both chick embryo and T. pyriformis was 8.0, with Tris-HCl buffer; activity of E. tenella thymidylate synthetase was still increasing at pH 8.2. The E. tenella enzyme was found to have a molecular weight of 4.6–4.9 × 105 daltons. The effects of nucleotides, inhibitors, and the omission of assay components on each enzyme are presented. Thymidylate synthetase from E. tenella is not greatly different from that of chick embryo, but does not resemble the enzyme from T. pyriformis. A case for using thymidylate synthetase as a chemotherapeutic target in the treatment of Eimeria infections remains. Indeed Eimeria may be considered as a model for infections caused by other protozoan parasites, such as Toxoplasma and Plasmodium, provided that suitable inhibitors can be found that are not toxic to the host.

Notes: SYNOPSIS. A protocol based on density differences between starved and fed cells and employing density gradient centrifugation has been devised to facilitate the isolation of auxotrophic mutants of cell lines derived from Tetrahymena thermophila strain B1868. First, a mass phenotype screening procedure was established whereby true auxotrophic mutants and slow-growing wild-type cells such as strain C* could readily be distinguished. Second, simulation experiments were performed in which wild-type cells starved first in non-nutritive buffer, then suspended in a defined medium lacking a single essential amino acid became significantly denser than the same cells when starved, then suspended in a complete defined medium. Finally, using the same protocol, a reconstruction experiment was carried out which resulted in effective separation of wild-type cells from cells of a tyrosine auxotroph. The overall procedure resulted in a 9-fold increase in the relative frequency of auxotrophic cells, while the density gradient centrifugation alone provided a 400-fold enrichment.

Notes: SYNOPSIS. Infectivity of Plasmodium gallinaceum (Brumpt) sporozoites isolated from midguts and salivary glands of experimentally infected Aedes fluviatilis (Lutz) was studied. The 2 populations were compared at 7, 8, and 9 days postisolation from mosquitoes, which were maintained at 27 C ± 1C and ∼75% relative humidity. Infectivity of the parasites was evaluated by the length of the prepatent period of the infection in 2-week-old chicks inoculated intramuscularly. Infection was caused by 7-day-old sporozoites from salivary glands, but not from midguts. Older sporozoites induced infection in all the inoculated chicks. The results suggested a somewhat higher infectivity of the 8- and 9-day salivary-gland parasites than of the oocyst sporozoites. However, unlike sporozoites from mammalian malaria, oocyst sporozoites from avian malaria were highly infective at this age.

Notes: SYNOPSIS. Sorogena stoianovitchae Bradbury & Olive, an epiphytic ciliate found in various parts of the world, has a trophic stage that feeds on members of the ciliate genus Colpoda. When grown in the presence of the food ciliate, it multiplies rapidly. When the cells become abundant they aggregate at the water surface on inserted plant fragments or floating pollen grains, the sides of culture dishes, or on floating films such as those deposited by bacteria or pollen grains. an aggregate mounds up and becomes ensheathed above the water level, after which the mass of cells called a sorogen rises aerially at the apex of a stalk deposited at its base. the tapering, noncellular stalk consists of a conspicuously furrowed sheath that encloses a mucilaginous matrix. At completion of stalk development the cells of the sorogen become encysted. the sorocysts are commonly discharged by fracturing of the drying sorus. Alternating light and dark conditions are required for sorocarp development.

Notes: SYNOPSIS. the antigenic types in populations of metacyclic trypanosomes of Trypanosoma brucei isolated from Glossina morsitans head-salivary gland trypanosome cultures and bloodstream forms in the early parasitemias produced from whole culture supernatant fluids containing metacyclic forms, were analyzed by the indirect fluorescent antibody test using clone-specific antisera. Metacyclic trypanosomes in cultures initiated with cloned bloodstream forms were heterogeneous with respect to their variable antigenic type (VAT). Trypanosomes comprising early parasitemias in immunosuppressed mice infected with metacyclics produced in cultures also had a range of VATs. Three of the VATs detected in the early parasitemias in mice have also been identified by other investigators in tsetse fly-transmitted populations of the same stock.

Notes: SYNOPSIS. A simple method is described for plating and cloning ciliates and other protozoa, based on a principle differing from that traditionally used for plating and cloning bacteria and other microorganisms. This procedure, referred to as the silicone-oil-plating-procedure (SOPP), involves vortexing small volumes of culture medium containing protozoa with larger volumes of a non-toxic silicone oil and plating the resulting unstable emulsion in small plastic petri plates. Discrete microdroplets of culture medium form containing protozoa entrapped and immobilized between the hydrophobic surfaces of the plastic petri dish and the oil. Protozoa, isolated by this method grow, divide, and multiply to form clones. the procedure may be used for plating and cloning protozoa in bacterized and axenic culture. Variations of the basic method may be applied to isolating protozoa from the wild, washing protozoa to remove microorganisms, screening for potential mutants, and for replica plating.

Notes: SYNOPSIS. Cyclic nucleotide phosphodiesterase [EC 3.1.4.17] was examined in Tetrahymena pyriformis strain NT-1. Enzymic activity was associated with the soluble and the particulate fractions, whereas most of the cyclic GMP phosphodiesterase activity was localized in the soluble fraction: the activities were optimal at pH 8.0–9.0. Although very low activities were detected in the absence of divalent cations, they were significantly increased by the addition of either Mg2+ or Mn2-. A kinetic analysis of the properties of the enzymes yielded 2 apparent KIII values ranging in concentration from 0.5 to 50 μM and from 0.1 to 62 μ M for cyclic AMP and GMP. respectively. A Ca2+-dependent activating factor for cyclic nucleotide phosphodiesterase was extracted from Tetrahymena cells, but this factor did not stimulate guanylate cyclase [EC 4.6.1.2] activity in this organism. On the other hand, Tetrahymena also contained a protein activator which stimulated guanylate cyclase in the presence of Ca2+, although this activator did not stimulate the phosphodiesterase. the results suggested that Tetrahymena might contain 2 types of Ca2+-dependent activators, one specific for phosphodiesterase and the other for guanylate cyclase.

Notes: SYNOPSIS. the cell size of Didinium nasutum was found to be dependent on the size of the Paramecium species available as prey. Didinium feeding on P. tetraurelia averaged 5.6 × 105μm3. the cell volume of Didinium increased with increasing prey size for the 5 prey species tested, to 9.1 × 105μm3 for Didinium feeding on P. caudatum. Didinium nearing a cell division ranged in size from 8.6 × 105μm3 on P. tetraurelia to 12.9 × 105μm3 on P. caudatum. the range in cell volume is such that Didinium feeding on P. caudatum are larger than the size at which Didinium divide when feeding on P. tetraurelia. This morphologic plasticity in cell volume allows Didinium to exploit a wide size range of Paramecium species as prey. It is proposed that the size of a Didinium may have profound effects on its ability to encounter and capture prey of different sizes.

Notes: RESUME. Chacun des 45–80 organelles adoraux de Bursaria truncatella O. F. Müller est constitué de 3 rangées de cinétosomes et l'aire buccale droite est couverte de nombreuses doubles rangées de cinétosomes. La stomatogenèse débute par la désorganisation et la résorption des organelles buccaux postérieurs. Puis, il y a désorganisation des rangées parorales de cinétosomes et multiplication des cinétosomes sur l'aire orale droite, en měme temps que sont rompues, selon une ligne oblique, un certain nombre de cinéties somatiques. La prolifération des cinétosomes aux extrémités des cinéties. de part et d'autre de la ligne de rupture, aboutit, d'une part, à la formation d'un champ anarchique qui est le primordium oral droit de l'opisthe, d'autre part, à la formation de nombreux doublets qui constituent chacun le primordium de chaque organelle adoral. Après la séparation des tomites, les cinétosomes de l'aire droite s'ordonnent en doubles rangées et les organelles adoraux se complètent par addition d'une 3ème rangée de cinétosomes. Les cinétosomes somatiques sont jumelés, reliés par 2 desmoses. Les fibres transverses postérieures et les fibres postciliaires forment de longs rubans de microtubules dirigés vers l'arrière et juxtaposés dans les crětes intercinétiennes. Les doubles rangées droites de cinétosomes buccaux sont assimilables à des stichodyades. Les organelles des cinétosomes adoraux portent des rideaux de fibres postciliaires convergents ou divergents. La rangée postérieure de chaque organelle est non ciliée. Par son type de stomatogenèse, par sa structure corticale, par l'ultrastructure des organelles adoraux, Bursaria appartient aux Colpodidea, ce qui suggère des remarques de plusieurs types.SYNOPSIS. In Bursaria truncatella O. F. Müller, each of the 45–80 adoral organelles is composed of 3 rows of kinetosomes, and the right buccal area is covered by many double rows of kinetosomes. Stomatogenesis begins by disorganization and disappearance of the posterior buccal organelles. Next, there is disorganization of the paroral rows of kinetosomes and multiplication of kinetosomes in the right oral area; at the same time, some somatic kineties are disrupted along an oblique line. Multiplication of kinetosomes at the extremities of the kineties, on both sides of the disruption, leads to the formation of an anarchic field which is the right oral primordium of the opisthe and the formation of doublets each of which constitutes an adoral organelle. After the separation of the tomites. the kinetosomes in the right buccal area position themselves, and the adoral organelles are completed by the addition of a 3rd row of kinetosomes. Somatic kineties are formed by successive pairs of ciliated kinetosomes united by 2 desmoses. the long posterior transverse ribbons and the postciliary ribbons extend posteriad, overlapping in the pellicular ridges. Oral rows of kinetosomes on the right can be compared with stichodyads. the adoral kinetosomes have convergent or divergent postciliary ribbons. the posterior row of kinetosomes in each organelle is not ciliated. By the type of stomatogenesis, the cortical ultrastructure, the ultrastructure adoral of its organelles, Bursaria belongs to the Colpodidea.

Notes: SYNOPSIS Free-living marine ciliates occur in the interstitial spaces of a wide vareity of filamentous and particulate substrata, on the surfaces of planar substrata, and in the plankton. In addition, they are found in association with a wide variety of plant and animal hosts. In this paper I review the progress during the past decade in understanding the distribution of marine ciliates, with particular emphasis on the relationship between ciliate biogeography and the species problem. It is concluded that as a general rule among marine ciliates, genera and species complexes are cosmopolitan. Specific locales may support a confusing array of sibling species or subspecific morphologic variants. Because the distributional processes and breeding biology of marine ciliates are only beginning to be understood, conventional ideas that marine ciliate species are cosmopolitan may require modification.

Notes: SYNOPSIS The subkingdom Protozoa now includes over 65,000 named species, of which over half are fossil and ∼ 10,000 are parasitic. Among living species, this includes ∼ 250 parasitic and 11,300 free-living sarcodines (of which ∼ 4,600 are foraminiferids); 1.800 parasitic and 5,100 free-living flagellates: ∼ 5,600 parasitic “Sporozoa” (including Apicomplexa, Microspora, Myxospora, and Aseetospora); and ∼ 2,500 parasitic and 4,700 free-living ciliates. There are undoubtedly thousands more still unmamed. Seven phyla of PROTOZOA are accepted in this classification—SARCOMASTIGOPHORA. LABYRINTHOMORPHA, APICOMPLEXA, MICROSPORA, ASCETOSPORA, MYXOSPORA, and CILIOPHORA. Diagnoses are given for these and for all higher taxa through suborders, and representative genera of each are named. the present scheme is a considerable revision of the Society's 1964 classification, which was prepared at a time when perhaps 48,000 species had been named. It has been necessitated by the acquisition of a great deal of new taxonomic information, much of it through electron microscopy. It is hoped that the present classification incorporates most of the major changes that will be made for some time. and that it will be used for many years by both protozoologists and non-protozoologists.

Notes: SYNOPSIS Leishmania donovani amastigote-to-promastigote transformation is inhibited by homogenates of infected hamster liver and spleen. This inhibitory activity is localized in the 100,000 g pellet fraction. Tests with lysates of adherent (macrophyages) and nonadherent (lymphocytes) spleen cells indicated that the inhibitory activity resided in the lymphocytes, specifically in the 100,000 g pellet fraction.

Notes: SYNOPSIS Antibodies induced in rabbits against Paramecium multimicronucleatum syngen 2 prevent sexually reactive cells from clumping, pairing, and forming cytoplasmic fusions. A biologic assay for the detection of these antibodies (designated blocking antibodies) is described. the blocking antibodies, unlike the immobilization antibodies, are produced against breis of sexually reactive cells and nonreactive cells of 2 types, nonstarved and immature. Isolated cilia from reactive cells of either mating type are weak immunogens for blocking antibodies. No correlation between the mating type specificity (III or IV) and these antibodies has been detected. Blocking antibodies can be absorbed with living cells, of which sexually reactive ones are the most effective absorbers, while immature ones are the least effective.

Notes: SYNOPSIS A method is described for the axenic mass cultivation of Paramecium tetraurelia strains 51s and 299s. the ciliate is grown in an enriched axenic medium developed by Soldo, Godoy & van Wagtendonk. Under continuous shaking on a rotary shaker, cultures were grown in one-liter Erlenmeyer flasks with 330 ml medium yield cell densities of 32,000 cell/ml and 20,000 cells/ml for strains 299s and 51s respectively. Doubling time is considerably shorter under these conditions than in the conventional static cultures. A 20-liter airlift bioreactor is described in detail which can be used successfully to otain up to 100 g wet weight of Paramecium in a single run; in this reactor the cell density reaches 38,000 cells/ml for strain 299s. and 23,000 cells/ml for 51s. This technic should facilitate the study of minor protein components of the ciliate.

Notes: SYNOPSIS The cadmium ion (Cd2+) was accumulated by Amoeba proteus in all cellular fractions, the highest level being associated with the cytosol fraction. On gel separation of the cytosol fraction, Cd-binding protein appeared in 2 peaks: one 〉45,000 MW (peak I) and the other 12,000 MW (peak II). Added cysteine increased the total Cd2+ taken up by the cells and resulted in disproportionate increase of Cd incorporated into the Cd-binding protein of peak II. the Cd-binding protein of peak II is analogous to the low-MW, Cdbinding proteins in Anacystis nidulans, Mytilus edulis, and to the metalloprotein of some vertebrates.

Notes: SYNOPSIS. The effects of some environmental influences on the cycle of Trypanosoma diemyctyli in Triturus v. viridescens are described. Bleeding of the host produced a reduction in the number of trypanosomes but did not affect their growth rate. The temperature at which the host was maintained affected the cycle of the trypanosomes. The length of the post-inoculation latent stage increased from 24 hours at 25°C. to an indefinitely long time at 5°C. The trypanosomes were found to be dimorphic. Adult parasites of the short form had a range of 45–75 μ and those of the long form of 76–116 μ. Growth rate of the trypanosomes was inhibited or greatly retarded at temperatures of 10°C. or lower and was greatest at 25°C. The size attained by the parasites and the number of parasites were greatest at 15°C. At this temperature the infection was pathogenic and the dimorphic parasites were in their long form. At the higher temperatures (20–25°C.) the infection was non-pathogenic with the trypanosomes in their short form.The infection is primarily one of adult newts. Experiments indicated that the larvae were resistant to the trypanosomes at all temperatures while the red efts were not. The latter are usually free from the trypanosomes because they are not exposed to them. Attempts to infect other newts and to locate any cryptic stages by the injection of blood and tissues from infected newts gave negative results.Starvation, sodium salicylate, and treatments used to control fungus infection of the newts had no detectable effects on the trypanosomes.

Notes: SYNOPSIS. A comparative study of five species of Tetrahymena, including thirteen strains, was made to ascertain their ability to act as facultative parasites. A variety of experimental hosts, including both vertebrates and invertebrates, were inoculated with axenic cultures of protozoa. Infections were numerous in both larval and adult insects. Tissues of living vertebrates were invaded by one species of Tetrahymena through artificially produced wounds.

Notes: SYNOPSIS. Unabsorbed, complement-inactivated antisera produced in rabbits were used in an immobilization system to study the serology of 31 strains of Tetrahymena pyriformis grown in axenic cultures at 26°C. Fourteen serological “groups” were found: 1. “H”: H, E, S, GC, L3, W, T, GHH, G1-R and sublines W-P and T-P; 2. “PR”: PR; 3. “GL”: GL; 4. “LR”: LR; 5. “L1”: L1 and L2; 6. “GP”: GP and Ch-S; 7. “WH”: WH6, WH14 and WH52; 8. “N”: N and HS; 9. “Y”: Y and TC; 10. “AA”: AA1, AA2 and AA4; 11. “F”: F and BF; 12. “Gf-J”: Gf-J; 13. “EZ”: EZ; 14. “Lava”: Lava. Not all of these “groups” were completely distinct; weak or variable cross-reactions occurring for particular cultures and antisera during the course of several years of observation suggested a relationship in terms of serotype potentialities, for strains in groups 1 and 2, and in groups 2, 3, 4, 5, and 6. Non-reciprocal cross-reactions are tentatively explained in terms of population fluctuations of serotype within particular cultures; several other suggested explanations remain possible. On the whole, however, the strains remained remarkably stable in dominant serotype.Observations on Tetrahymena in paralyzing antisera, with respect to the extrusion of a gelatinous exudate, in general confirmed previous observations by others. “Chain” formation was noted upon recovery, under conditions suggesting that the chains do not always derive entirely from incomplete cytokinesis of dividing organisms but that at least sometimes an aggregation of separate individuals is also involved. Synchronized division was observed for recovering organisms. A gelatinous material was obtained by centrifugation of a large number of individuals; this material provided a degree of protection to the organisms against antiserum effects while other colloidal materials did not, but the protective effects proved nonspecific in the sense that they were not confined to particular strain-antiserum combinations.

Notes: SYNOPSIS. A rapid quantitative method for measuring trypanostatic activity by means of the nonpathogenic flagellate Herpetomonas culicidarum is described. Of the known trypanocidal agents tested, pentamidine was the most active; stilbamidine and propamidine somewhat less active. H. culicidarum is more resistant to these agents than are some pathogenic hemoflagellates. Two new antifungal antibiotics, nystatin and heptamycin (a candicidin-like antibiotic), had powerful trypanostatic activity in vitro. The potential trypanostatic activity of antifungal agents is noted.

Notes: SYNOPSIS. Approximately fifty % of Natrix piscator from the vicinity of Bombay showed a haemogregarine in the peripheral blood. Schizogonic stages were found in great abundance in the lung capillaries, and occasionally in other internal organs. No parasites could be demonstrated in trombiculid mites of the genus Schongastia fed on infected snakes. Various developmental stages were found in the leech, Hirudinaria granulosa allowed to feed on infected Natrix piscator. The haemogregarine was originally described from this host in Ceylon on the basis of blood stages only and was named Haemogregarina mirabilis. Although the parasite exhibits several of the characters diagnostic of the schizogonic stages of the genus Hepatozoon, it is advisable for the present to retain it in the genus Haemogregarina.

Notes: SYNOPSIS. A new species of a freshwater reticulate dinoflagellate, Woloszynskia limnetica, is described. The membrane structure and the shape of the membrane plates change during cell development. The rod-shaped mitochondria found among the membrane plates disappear in the adult cells; they constitute a center from which starch grains develop. Mitochondria also occur free in the endoplasm. Different physiological activities appear to be performed by morphologically identical chondriosomes. The stigma changes in different phases of the life cycle. The physicochemical properties of the ectoplasm govern the formation of specific structures of the membrane plates, which in turn determine the taxonomic position.

Notes: SYNOPSIS. Pseudomicrothorax dubius, a rather rare protozoon assigned by Kahl to the trichostome order of ciliates, has been found and positively identified for the first time in America, and its morphology and morphogenesis have been studied in detail with the aid of modern techniques. The Chatton-Lwoff silver impregnation method is considered indispensable in acquiring an understanding of the ciliate's infraciliature: both its anatomy in the mature vegetative animal and its activities during the morphogenetics of binary fission.Stomatogenesis is of a complex type, considered here as “semi-autonomous” in nature, although a single, true stomatogenous meridian also is involved. Details of this explicit morphogenetic phenomenon are offered.The presence of a true zone of three adoral membranelles, never before recognized with any accuracy in this ciliate, a buccal cavity and associated structures, and the mode of stomatogenesis have led the writers to propose transfer of the genus Pseudomicrothorax from the Trichostomatida to the order Hymenostomatida.

Notes: SYNOPSIS. Studies of the body ciliature of Balantidium coli and B. caviae (?) after Breslau's opal-blue and Klein's silver nitrate techniques revealed a preoral-dorsal suture area where some of the ciliary rows fail to reach the peristomial margin. The incomplete kineties ranged up to a dozen in number and were variable in arrangement. In a count of 100 specimens of B. caviae (?) the incomplete kineties were at the right of the suture in 39, at the left in 24 and on both sides of the suture line in 37. At the posterior end not many kineties reach the pole but no sutural pattern was seen in that region. Scattered irregularities in the ciliary rows were sometimes seen.Studies of the oral region tend to confirm the view of Fauré-Fremiet that the peristomial ciliature consists of short rows of cilia which are continuations of the anterior body kineties. Membranelles were not found. Thus, some species of Balantidium, at least, show affinities with the Holotricha in agreement with Nie and Fauré-Fremiet.Fission commonly produces two equal-sized daughters but many cases of unequal division were observed. In both these species conjugants are much smaller than vegetative animals and two preconjugant divisions are indicated, the first of which may be unequal.During the early stages of fission, the anterior ends of the kineties of the posterior daughter change direction, becoming oblique in the fission zone. In this region the kinetosomes multiply; possibly some of the kineties also divide but evidence for this is incomplete. No evidence of reorganization at the anterior end of the anterior daughter was seen.Attempts to infect hamsters with B. coli and B. caviae (?) failed. No parasites were found in two collared peccaries repeatedly examined.

Notes: SYNOPSIS. Purification by migration on solid agar plates was studied with a small soil amoeba, Acanthamoeba sp., and a large fresh-water amoeba, Amoeba proteus. Purification seems accomplished largely by two mechanisms: egestion and attrition of contaminating organisms. Digestion may also play a role but probably is less important. The migration method is applicable to motile forms of the two amoebae which differ greatly in volume and motility. Therefore the method may be of potential value in purifying many species. Modifications which should extend the usefulness of the method are considered.

Notes: SYNOPSIS. The gametes of Trichonympha grandis fuse quite differently from those of all the other species of Trichonympha in Cryptocercus; fusion is partial and temporary instead of complete and permanent as in other species. In this species, as in the others, fusion brings about the disintegration of all the extranuclear organelles of the male gamete, but none of those of the female; these persist to become the organelles of the zygote. Gametic union accomplishes two things: loss of extranuclear organelles of male and fusion of pronuclei. Unlike that of the other species of Trichonympha, the cytoplasm of the male gamete of T. grandis contributes slightly, if at all, to the formation of the zygote.

Notes: SYNOPSIS. A new species of Hepatocystis (H. hippopotami) is described from the blood and liver of a Rhodesian hippopotamus (Hippopotamus amphibius). Its relationship with other members of the genus is briefly discussed.

Notes: SYNOPSIS. The role of eleven different types of achromatic figures in chromosomal movement of Barbulanympha is analyzed. When only one pole is present, no chromosomes are ever connected with it, and hence they do not move. The chromosomes go through their usual life cycle including pairing, but remain in the parent nucleus, which, of course, does not divide. When two poles are present with only one pole near the nucleus, the poles, which are the distal ends of the elongate centrioles, do not cooperate in the formation of a central spindle and the chromosomal behavior is just as if there were only one pole—no movement. The same is true when more than two poles are present with only one near the nucleus.Unless a central spindle is present, movement of chromosomes never occurs. However, when many central spindles are present, sister chromosomes may separate and move to poles which are not directly connected by a central spindle. In other words, sisters may separate without moving along a central spindle.In binucleate cells with one central spindle the chromosomes of one nucleus move to the poles, but those of the other do not. Movement always occurs in the nucleus that has its nuclear membrane depressed by the central spindle. When two or more central spindles are present, the chromosomes of both nuclei may move to the poles.

Notes: SYNOPSIS. Euplotes eurystomus Wrzesniowski was cultured on bacterial media with Tetrahymena pyriformis serving as the food organism. Animals were injured with various types of operations using the Chambers' micromanipulator. These animals were followed during the course of their regeneration using various nuclear stains, silver impregnation techniques and vital staining methods. It was found that two cirral fields arose as a result of injury removing one or more of the locomotor organelles and that the posterior field was soon resorbed, while the anterior one replaced all of the old cirri of the regenerating animal. In addition, in response to this sort of injury, complete nuclear reorganization took place. Animals which were injured in a manner not affecting the locomotor organelles directly, responded by proliferating a fine network in the area of injury. This network seemed to reinforce the injured area and persisted until the next binary fission of the animal. No nuclear reorganization took place in these cases.

Notes: SYNOPSIS. The leech, Erpobdella sp., is a suitable invertebrate host for Trypanosoma ambystomae. The developmental cycle involves a mononucleate, rounded body derived from the bloodstream form; this body then transforms into a large plump crithidia. Subsequent divisions yield medium crithidia, small crithidia, and ultimately, metacyclic trypanosomes.

Notes: Books reviewed in this article:Larwood, G. & Rosen, B. R., eds. 1979. Biology and Systematics of Colonial Organisms.Hellebust, Johan A. & Craigie, J. S. eds. 1978. Handbook of Phycological Methods. Physiological and Biochemical Methods.

Notes: SYNOPSIS. Surface saccharides in 2 Trichomonas vaginalis strains, the moderately pathogenic, JH34A, and the mild, JH162A, were analyzed with the aid of plant lectins. Concanavalin A (Con A), wheat germ agglutinin (WGA), soybean agglutinin (SBA), castor bean agglutinin (CBA), and lectin from the garden pea (GPA) were employed in agglutination tests and in treatment of ultrathin sections for electron microscopy according to the horseradish peroxidase-3,3′-diaminobenzidine method. With Con A and WGA, small quantitative differences were noted between the 2 strains in the results of agglutination and in the reaction-product deposits observed by electron microscopy. Distribution of the binding sites for the 2 lectins was also somewhat different in the JH34A and JH162A trichomonads. In general, the reactions with the more pathogenic strain were slightly stronger. Although the reactions with SBA and CBA lectins were weaker than those with Con A or WGA, they provided the means for qualitative differentiation between the 2 trichomonad strains. SBA alone agglutinated the JH34A strain and formed demonstrable deposits on the cell surfaces. On the other hand, only CBA reacted with JH162A flagellates. The garden pea lectin failed to bind to the surface of either strain. On the basis of results obtained with the control preparations incubated in the presence of specific inhibitors, it was concluded that both strains had α-methyl-D-mannoside and/or α-methyl-D-mannoside-like as well as N-acetyl-D-glucosamine residues on their surfaces. In addition, JH34A strain had D-lactose-containing residues while JH162A trichomonads had residues with D-galactose. Neither strain appeared to possess residues containing N-acetyl-D-galactosamine.

Notes: SYNOPSIS. Centrifugation for 30–40 seconds at 8,000 g has been used to render monopodial specimens of the large free-living ameba. Chaos carolinensis. These monopodial amebae exhibit obvious torsional movements in the tail. In many cases the posterior ectoplasm assumes the form of a screw with helical ridges forming in place of the more common straight dorsal fins. This finding prompted a re-examination of normal polypodial C. carolinensis, and a majority of these were found also to exhibit torsional movement in the tail and in retracting pseudopodia. These movements suggest that the cytoskeleton of Chaos may have a helical component in its organization.

Notes: Books reviewed in this article:Levandowsky, M. & Hutner, S. H., eds. Biochemistry and Physiology of Protozoa.Raymont, John E. G. with J. D. Burton & K. R. Dyer. 1980. Plankton and Productivity in the Oceans. Vol. I. Phytoplankton.

Notes: Book reviewed in this article:Maramorosch, Karl & Hirumi, Hiroyuki, eds. 1979. Practical Tissue Culture Applications.

Notes: SYNOPSIS. Cysteine and ascorbic acid were previously shown to be required by Entamoeba histolytica trophozoites for attachment to glass, elongation, and ameboid movement as well as for short-term (12–24 h) survival in a balanced salt solution containing bovine serum albumin and a vitamin solution (Maintenance Medium 1). If the only function of cysteine and ascorbate was to decrease the redox potential, other reducing agents should be effective. However, the requirement for cysteine in the presence of ascorbic acid was highly specific. Equally effective were D- and L-cysteine; however, of many other compounds tested, only thioglycolic acid, ascorbic acid, or L-cystine (in decreasing order) were somewhat active. Under N2 atmosphere, cysteine and ascorbic acid were still required, although their concentrations could be halved. The ability to attach in the maintenance medium was irreversibly lost after only 5 min of cysteine-ascorbic acid deprivation; however, there was no decrease in viability when the amebae were transferred to growth medium within 30 min. Cysteine thiol groups in the medium were oxidized rapidly regardless of the concentration of ascorbic acid or the presence of amebae; however, ascorbic acid prolonged attachment of amebae.

Notes: SYNOPSIS. Low concentrations of chlorpromazine (∼0.01 mM) inhibit growth and nucleic acid synthesis in the ciliate Tetrahymena pyriformis. Brief exposure of the cells to, e.g. 0.018 mM chlorpromazine, had very little effect on 14CO2 production or on label incorporation into glycogen from [1-14C]glucetate, [6–14C]glucose, or [1-14C]leucine, but 17-h exposure of stationary phase cultures to this drug caused marked alterations in metabolism, including an almost complete loss of ability to decarboxylate L-[1-14C]leucine and L-[1-14C]tyrosine. It was shown that loss of ability to decarboxylate these amino acids results from loss of ability to transport them.

Notes: SYNOPSIS. A survey of 41 herbivorous mole-rats, Spalax ehrenbergi Nehring, in Urfa, Adiyaman, and Maras provinces of Turkey revealed 7 new species of Eimeria in addition to previously described Eimeriidae. The shape, average dimensions (in μm) of their oocysts, and the numbers of hosts from which the new species were isolated were as follows: Eimeria urfensis sp. n., ellipsoidal (33 × 21), from 8 hosts; Eimeria adiyamanensis sp. n., ovoid to ellipsoidal (33 × 18), from 6 hosts; Eimeria haranica sp. n., elongate ovoid (37 × 20), from 22 rats; Eimeria marasensis sp. n., ellipsoidal (36 × 18), from 2 rats; Eimeria oytuni sp. n., pear-shaped (24 × 17), from 2 hosts; Eimeria celebii sp. n., ellipsoidal (16 × 9), from 1 rat; and Eimeria torosicum sp. n., spherical to subspherical (11 × 10), from 2 animals.

Notes: Defined media are described that support 14-20 h generation times for Acanthamoeba castellanii and A. rhysodes in monolayer cultures. the media differ in minor ways from previously described media, but the growth rates are greatly improved over previously reported values. Maximum growth rates were observed for A, castellanii in a complex medium containing 21 amino acids, but near-maximum rates could be achieved in relatively simple media containing 9 amino acids. Growth occurred with 6 amino acids, as reported by others, but generation times exceeded 30 h. Amitosis was a common problem during early subcultures in defined media, but became infrequent after repeated transfers. Synchronous encystment resulting in 70-80% cyst formation could be induced in the defined media by glucose and acetate starvation. the rate of encystment varied with cell density at the time of starvation and was optimal at initial densities of 400-800 amebae/mm2.

Notes: Tetrahymena pyriformis strain HSM secretes 4 isozymes of hexosaminidase. Purified isozymes B1 and B2 are eluted from the void volume of a concanavalin A-Sepharose column, suggesting that they are not glycosylated. Purified isozymes A1 and A2 bind to the column and are eluted at ∼0.1 M α-methylmannoside, suggesting that these isozymes are glycoproteins. In agreement with earlier deductions based on a differential kinetic assay for the A and B isozymes, the elution pattern of hexosaminidase activity from material secreted by cells grown to early and late stationary phase was consistent with these secretions containing primarily the B and the A isozymes, respectively.

Notes: The surface proteins and glycoproteins on red cells from normal and Babesia bovis-infected calf blood have been compared. Several radiolabeling probes were used to label specifically external membrane molecules which were then separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by autoradiography or fluorography. No differences were observed among the Coomassie Blue-stained membrane proteins of erythrocytes from individual uninfected calves. Comparison of red cells from these animals also indicated no qualitative differences in the surface proteins with accessible tyrosyl residues labeled by lactoperoxidase-catalyzed radioiodnation, although some quantitative variation in the uptake of radioactivity into particular proteins was observed. the major radioiodinated bands on normal bovine erythrocytes had Mr of 165, 130, 90, and 45 kiloDaltons. However, labeling of surface glycoproteins by the periodate/[3H]NaBH4 and galactose oxidase (± neuraminidase)/[3H]NaBH4 methods showed significant differences in the surface proteins of red cells from individual uninfected calves. of 14 animals tested, 5 had major labeled glycoproteins of unique Mr. No changes were observed in radioiodinated surface proteins of total red cell samples from infected calves with 0.5-6% parasitemia. Radioiodination of concentrated infected red cells from the same samples (concentrated by selective hypotonic lysis of uninfected erythrocytes in KC1) resulted in the labeling of 3 new surface proteins, with Mr of 118, 115, and 60 kiloDaltons. the same new 125I-labeled bands were identified on infected cells from 3 avirulent strains of B. bovis used in vaccine production. Furthermore, in concentrated infected cells there was very poor radiolabeling of major bands strongly labeled on uninfected cells (Mr 165, 130, and 90 kiloDaltons), suggesting parasite-induced loss of these proteins. Although there were some differences in 3H-labeled surface glycoproteins of red cells from normal and. B. bovis -infected blood, they were restricted to minor labeled bands and were not seen consistently. the labeled surface glycoproteins of concentrated infected cells were very similar to those of the uninfected red blood cells from infected blood.

Notes: SYNOPSIS. California ground squirrels (Citellus beecheyi) were found to be infected with trypa-nosomes whose most striking morphological features are an unusually large kinetoplast and a long, tapering posterior end. The total length is 25.2 μ, and body length is 18.0 μ. This “lewisi”-type species is compared with other trypanosomes reported from American ground squirrels, but a specific diagnosis is not made because the life cycle has not been observed and because morphological features of trypanosomes are known to vary widely under differing environmental conditions.

Notes: SYNOPSIS. The basal apparatus of the flagella and kinetoplast in Leishmania donovani have been studied with the electron microscope. The flagellar fibrils extend into the body of the protozoan to form the kinetosome. At the point of origin of the flagellum, the pellicle invaginates to form a kinetosomal vacuole around the kinetosome. The kinetoplast is formed by a transversely elongated banded structure, surrounded at some distance by a double layered kinetoplast membrane. There is no apparent connection between the kinetosome and the kinetoplast.

Notes: SYNOPSIS. Starvation of Isotricha prostoma for 72–96 hours decreased the cellular amylopectin granules and facilitated the microscopic search for bacterial feeding. I. prostoma selected and ingested only certain rods from among many types of rumen bacteria. In order to isolate the bacteria important as a food source for Isotricha, the starved protozoa were allowed to feed on mixed rumen bacteria, washed, and the crushed protozoan contents quickly cultured for bacteria. Several strains of bacteria were isolated in pure culture. Three of the rod strains isolated were rapidly ingested by I. prostoma when fed to the ciliate. In a monobacterial culture I. prostoma divided once before succumbing.

Notes: SYNOPSIS. Cultures of Trypanosoma theileri were obtained at 36° and at 37.5°C. in a blood-lysate medium inoculated with blood from three dairy cows showing subnormal milk production. The organisms were first seen after 4 days in the first subculture, reached a maximum number of about 500,000 per ml. on the 4th day of the second subculture, and attained about this same number on the 4th day of subsequent transfers. Crithidial forms predominated but trypanosomes of the blood-stream type were also numerous. Cultures were not obtained from cows with normal milk production. The infected cows, although free from helminth parasites, showed a marked eosinophilia.

Notes: SYNOPSIS. A new species of Paramecium, P. jenningsi, n. sp., from South India, is described. It is like P. aurelia except that nuclei are larger, the cell size is somewhat larger, and the macronuclear anlagen (“placentae”) have long-persisting chromatinic centers.

Notes: SYNOPSIS. The nutritional requirements of 3 isolates of Prymnesium parvum (2 Israeli, 1 Scottish) included vitamin B12 and thiamine. For comparison, 2 other brackish chrysomonads were studied: Monochrysis lutheri isolated by Droop in Scotland and Isochrysis galbana purified by McLaughlin from a culture obtained from the Plymouth laboratory.The isolates of Prymnesium parvum and Isochrysis galbana had a molecular B12 specificity like Ochromonas malhamensis: no response to Factor B, pseudovitamin B12, Factor A or Factor H. M. lutheri, in contrast, responded to pseudovitamin B12, Factor H, and Factor A.Thiamine was essential; 1.0 μg.% allowed full growth of P. parvum. The NaCl concentration for good growth was 0.3–5.0%; growth was possible from 6–12%. Dark growth was not achieved.Ammonia, as suggested from its use in suppressing outbreaks of P. parvum, was sharply inhibitory, less so at high concentrations of NaCl or at acid pH.Nitrate, ammonia, arginine, asparagine, methionine, histidine, alanine, glycine, serine, proline, leucine, isoleucine, tyrosine, aspartic and glutamic acids, acetylurea, and creatine served as nitrogen sources in both acid and alkaline media.The phosphate requirement of P. parvum and M. lutheri and Isochrysis galbana was satisfied by inorganic phosphate, commercial glycerophosphate, yeast adenylic acid, cytidylic acid, monoethyl phosphate, and riboflavin monophosphate.Laboratory cultures in defined media of the isolates of P. parvum were toxigenic to Lebistes and Gambusia. Culture fluids from alkaline media were more toxic than those from acid media, as previously noted in Israel.Culture media suitable for production of large quantities of these organisms were developed.

Notes: SYNOPSIS. Certain aspects of the metabolism of a Trichomonas batrachorum-type flagellate from the cecum of swine were studied. This trichomonad (1) oxidized glucose, mannose, maltose, sucrose, and inulin, (2) was incapable of oxidizing Krebs' cycle intermediates, (3) possessed peroxide-splitting capabilities, (4) was inhibited by only iodoacetate and arsenite, and (5) formed acid(s) aerobically. Although there was no effect on oxygen uptake, pyruvate and lactate increased the anaerobic evolution of gas(es). In addition to CO2, other gas, not absorbed by KOH, was produced anaerobically.Compared with other porcine trichomonads, the metabolism of this small trichomonad resembles most closely that of the large cecal trichomonad, T. suis. However, the smaller trichomonad had a generally lower respiratory rate, a slightly lower optimal pH, and failed to oxidize fructose, galactose, lactose, raffinose, and trehalose.

Notes: SYNOPSIS. The “dry” silver method is redescribed with special attention to the possible difficulties encountered in its use. This method first revealed the silverline or neuroformative system of the ciliates, and is considered the best method for the demonstration of this structure. The valuable results obtainable with this technique are pointed out and illustrated with appropriate photomicrographs.

Notes: SYNOPSIS. It has been assumed by others that green euglenas and derived bleached forms are physiologically equivalent except for chlorophyll and plastids. Some workers, however, have remarked upon differences which might depend on the mode of bleaching.Several hitherto undescribed chlorotic substrains of E. gracilis var. bacillaris were examined for pigment alteration, growth under a variety of conditions, and ability to withstand high temperature. These studies indicated physiological variation in the different chlorotic substrains. Although all were apparently chlorophyll-less and aplastidic, only one seemed completely achromatic. The carotenoid content of others varied. Metabolic changes manifested by altered pigmentation may reflect enzymatic variation caused by the chlorosis-inducing agents.

Notes: SYNOPSIS. Thin sections of Amoeba proteus, fixed in osmium tetroxide and embedded in methacrylate, were examined in the electron microscope. The fine structure of various protoplasmic components is described. The plasmalemma, or cell membrane, varies in thickness and structure. These variations may be due to variations in physiological state, or they may be due to differences in preparation. Along its cytoplasmic edge is always present a definite line approximately 0.01 to 0.02 μ thick. The mitochondria, or beta granules, exhibit a structure similar to that of the mitochondria of several other protozoa and comparable to that of the mitochondria of other animals. In definite association with the membrane of the food vacuole are dense, rounded particles which in size are below the limit of resolution of the light microscope. Such dense particles are much less frequently present in the hyaloplasm and in association with the plasmalemma. A possible relationship to the neutral red granules associated with food vacuoles of Paramecium is suggested. The contractile vacuole possesses a thin membrane surrounded by a much thicker circum-vacuolar zone of irregular strands which may form a three-dimensional network around the membrane. This may represent the contractile element of the vacuole. A single layer of mitochondria is closely apposed to the circum-vacuolar zone. Many small vacuoles and irregular vesicles are present throughout the cytoplasm. At times there occur groups of small, thin-walled vesicles, which may correspond to an endoplasmic reticulum. The nuclear envelope consists of a thick inner porous layer and a thinner outer layer that is continuous yet is marked by the presence of numerous small annuli, each apparently surrounding a pore. In its structure, this outer layer appears to correspond to the entire nuclear envelope of many other cell forms.

Notes: SYNOPSIS. Irradiation of Stentor coeruleus with Xray doses of 150–300 kr inhibited growth in size and fission. The irradiation also led to the development of structural abnormalities, which appeared about a day after irradiation. The inhibition of growth and fission was independent of the oxygen concentration during irradiation, but the abnormalities were produced at lower doses in nitrogen than in air. Regeneration of parts removed by cutting occurred even at the highest doses at essentially normal rate even during the period when over-all growth was completely inhibited. The conclusion is drawn that delay in fission by radiation is a secondary consequence of inhibition of growth and not a consequence of blocks in the specific morphogenetic processes required for division.

Notes: SYNOPSIS. A description is given of the formation of an unusual type of achromatic figure by two very long, narrow centrioles. The unique manner in which this structure functions in chromosomal movement is explained.

Notes: SYNOPSIS. Traditionally, observations on the nature of protozoa have been published in periodicals or books, or remain buried in research notebooks. The retrieval and processing of information on a particular species or strain are dependent solely upon individual investigators. Although various modern methods have been applied to the study of protozoa, no attempt has been made to develop a system with which information on protozoan strains can be stored, retrieved easily, and processed for various analyses by computer technology. Based upon an existing system for encoding data on bacterial strains, a complementary system applicable to protozoan strains was developed and is described herein.

Notes: SYNOPSIS. The development of Sarcocystis cruzi Hasselmann (syn. S. fusiformis Railliet) meronts was studied in seven 7- to 10-day-old calves killed 4, 7, 11, 15, 22, 25 and 28 days postinoculation (DPI) with 5 × 107 sporocysts from feces of coyotes. No meronts were found 4 and 7 DPI. Young and intermediate meronts with 1–16 nuclei were found in endothelial cells of arteries in mesenteric lymph nodes, but not in kidneys 11 DPI.Mature meronts were noted in endothelial cells of arteries, arterioles, or capillaries of many organs of calves killed 15 to 25 DPI. No first-generation meronts were found 28 DPI. By electron microscopy, all stages of the first-generation merogony were found free within the host cell cytoplasm and not within a parasitophorous vacuole. The appearance of intranuclear spindles preceded the formation of merozoites by endopolygeny. Mature meronts measured 41.0 × 17.5 (34–50 × 15–24) μm, contained ∼ 100–350 merozoites, and had 2 to 4 relatively small residual bodies, 2.8 μm in diameter. Merozoites measured 6.3 × 1.5 (5.5–7 × 1 μm) and contained most of the organelles characteristically found in coccidian merozoites. Micropores were observed in merozoites, but not in young and intermediate meronts. Merozoites were seen free in the lumen of blood vessels, in intracellular areas, and free within the host cell cytoplasm.

Notes: SYNOPSIS. Myxidium spores from various eel hosts (Anguilla spp.) are compared. Myxidium anguillae, M. enchelypterygii, M. illinoisense, M. serum, and M. zealandicum are synonymized with M. giardi, a ubiquitous species reported from A. anguilla, A. rostrata, A. mossambica, A. japonica, A. reinhardtii, A. bicolor pacifica, A. australis, and A. dieffenbachii. Myxidium uchiyamae, M. lentiforme, M. matsuii and M. acinum are retained, and 2 new species described. Species other than M. giardi appear to be restricted to the Indo-Pacific region.

Notes: SYNOPSIS. A new species of kinetophragminophoran ciliate, collected from dried vegetation and capable of forming an aerial sorocarp, is described and named Sorogena stoianovitchae gen. n., sp. n. This ciliate is a voracious predator that feeds on species of Colpoda, and, when the latter is depleted in numbers, aggregates to forms sorogens. Each sorogen rises into the air from the surface of the water, forming a secreted stalk with a sorus of cysts at its apex. the feeding stage of the ciliate resembles an Enchelys in that it has an apical, slit-like mouth surrounded by a lip, a somewhat dorso-ventrally flattened body, and meridional kineties. Its length ranges from 40–75 μm and width from 23–55 μm. It has a typical rhabdos type of cytopharynx, but no specialized oral ciliature. the somatic kineties are formed of rows of paired kinetosomes with associated microfibrils, the arrangement of which differs a little from that of other ciliates of this subclass. Sorogena has tentatively been placed in the order Haptorida although it lacks toxicysts, recognizable mucocysts, and clavate cilia. Its unique life cycle and some of the details of its fine structure indicate differences between Sorogena and other haptorids so profound that a new family, SOROGENIDAE, is created for it. the type species (PNG76-73) was collected on dry figs at the Wau Ecology Institute, Papua New Guinea.

Notes: Cell surface pellicular membranes (PM) were isolated from promastigote forms of Leishmania donovani by differential and discontinuous sucrose gradient centrifugation procedures. the PM had a density equivalent of ∼ 1.19 g/cm3. As ascertained by electron microscopy, longitudinal parallel arrays of subpellicular microtubules (MT) remained attached to the isolated PM inner lamina, and this feature was used to assess membrane fraction purity. Gradient fractions having ∼ 95% of all membranes combined with MT were obtained routinely. the attached MT imparted a structural asymmetry to the PM permitting uniequivocal identification of the membrane external and cytoplasmic surfaces. the supramolecular structure of attached MT was evident in negatively stained PM. In ultrathin sections, PM had a mean width of ∼ 7.2 nm and attached MT a diameter of ∼ 29 nm. the MT were apparently cross-bridged both to each other and to the PM via a flocculent filamentoid nexus. As determined by sodium dodecylsulfate-polyacrylamide gel electrophoresis, isolated PM contained ∼ 40 peptide bands ranging in apparent molecular weight from ≤ 1.2 × 104 to ≥ 2.2 × 105daltons. of these, 19 were stained with periodic acid-Schiffs’ reagent suggesting that most PM carbohydrate constituents were present as glycopeptides. A presumpative glycolipid/polysaccharide PM constituent was also identified in such gels.

Notes: Organic requirements for attachment to glass, elongation, and motility of Entamoeba histolytica, have been determined. the trophozoite, which has been grown axenically only in highly complex media with reduced oxygen tensions, remains rounded and detached when placed in a Tris-HCl buffered solution containing NaCI, KCI, MgCI2, and CaCI2. A maintenance medium in which the amebae could attach to glass, elongate, and remain motile and viable for 12 to 24 h was devised with the addition of cysteine, ascorbic acid, bovine serum albumin, and the vitamin solution of medium NCTC #107. Tris-HCI was the most effective buffer tested and the optimal pH was 6.9 to 7.0. Survival, but not attachment, of the amebae was decreased at osmolalities ranging between 110 and 180 milliosmoles/kg, whereas both functions were decreased above ∼260 milliosmoles/kg. Bovine serum albumin, the most effective of the proteins tested, and the vitamin solution helped maintain attachment of some ameba strains, but were not required by other strains. the requirements for cysteine and ascorbic acid were absolute and highly specific. During incubation in the maintenance medium, cell volumes decreased. Sensitivity of the organisms to agglutination by concanavalin A, wheat germ agglutinin, soybean agglutinin and fucose binding protein remained unchanged.

Notes: SYNOPSIS. Differences in the composition and distribution of cell membrane carbohydrates were demonstrated in the 3 life cycle forms of 3 Trypanosoma cruzi strains by using lectins with different specificities. The results suggest that lectin binding may be useful in characterization of the parasite strains.

Notes: SYNOPSIS. Promastigotes of Leptomonas sp., a flagellate parasite of the silkworm, Bombyx mori, multiplied by binary fission with the following sequence of events: duplication of the flagellum; division of the kinetoplast and the nucleus; spatial separation of the kinetoplast: and cytokinesis resulting in the formation of 2 daughter promastigotes. In the early stages of encystment, promastigotes aggregated in a rosette and assumed a stumpy form. The nucleus and kinetoplast of the stumpy promastigotes were double, suggesting a possibility of fusion of the organism in the rosette. When most of the promastigotes in the cluster became stumpy, each individual was isolated from the cluster and acquired a thick coat with an acidophilic substance, thus forming a cyst.

Notes: Book reviewed in this article:Gantt, Elisabeth, ed. 1980. Handbook of Phycological Methods. Developmental and Cytological Methods.

Notes: SYNOPSIS. Doublet Paramecium tetraurelia would be expected to contain 2 macronuclei if their nuclear complement were strictly analogous to that of singlets. However, most doublets are unimacronucleate. It is shown in this study that dimacronucleate cells are present only in young clones. Unimacronucleate cells arise either through abnormalities in the determination and distribution of macronuclear anlagen during the first cell cycle after conjugation, or from dimacronucleate cells through abnormal division and segregation of macronuclei during the fission process.When a change in the number of macronuclei occurs through abnormalities in the division and segregation of daughter macronuclei, the daughter cells produced typically have DNA contents more similar than those expected from either random segregation of daughter macronuclei, or from the normal segregation pattern in ciliates in which changes in the number of macronuclei in progeny cells do not occur. This suggests that part of the regulation process of macronuclear DNA content in Paramecium may occur through control of the segregation pattern of daughter macronuclei.

Notes: SYNOPSIS. The relation of humoral antibody response to protection was evaluated in mice immunized with whole homogenates of Trypanosoma cruzi or with its flagellar fraction by direct agglutination and indirect fluorescent antibody test as well as by lytic and neutralizing activity against blood trypomastigotes. The results indicated that lytic antibodies were not implicated directly in protection against these trypanosomes. It was evident from histopathologic examination that the higher the degree of protection achieved, the lower the tissue damage observed in the challenged mice. Serum-neutralizing activity was highest in the groups protected most effectively.

Notes: SYNOPSIS. We have examined various properties of DNAs from 7 dinoflagellate isolates of wide geographic distribution; all of the isolates are superficially indistinguishable from a laboratory strain of Crypthecodinium cohnii originally isolated at Woods Hole, Massachusetts (WHd strain). Two isolates, one from Puerto Rico and the other from Honduras, are clearly distinguishable from WHd and the other isolates by their DNA buoyant density values. WHd and the other 5 isolates we have examined are indistinguishable from one another in terms of DNA buoyant densities and melting temperatures. The relationship among the various isolates, including WHd, were evaluated at a finer level through restriction endonuclease cleavage and molecular hybridization to compare ribosomal RNA gene structure in the several DNAs. All the isolates could be further categorized by this method, the patterns of restriction endonuclease cleavage of ribosomal RNA genes in the isolates paralleling exactly their sexual compatibilities established from breeding experiments by Beam & Himes. The DNAs were also treated with a restriction endonuclease sensitive to the presence of the modified base 5-methylcytosine. In all isolates, cytosine residues in both total DNA and DNA specifically containing the ribosomal RNA genes were found to be extensively methylated, as was previously shown for the WHd strain.

Notes: SYNOPSIS. Chemical procedures remove some of the outer 3 limiting membranes of 2 ciliate protozoa, Euplotes eurystomus and Tetrahymena pyriformis, and reveal sheets of microtubules in their ectoplasm for SEM study. This greatly enhances the analysis of the 3-dimensional geometry of these sheets, as is shown especially for E. eurystomus. In this organism, sheets of microtubules can readily be observed and described as they course through or around parts of the oral apparatus and other 3-dimensionally complex regions.

Notes: SYNOPSIS. A large, external glycoprotein with antigenic properties isolated from the ciliate Pseudomicrothorax dubius was found to have a molecular weight of ∼ 250,000 daltons. Analysis of the extracts by isoelectric focusing in combination with immunodiffusion and gradient polyacrylamide gel electrophoresis revealed that the principal antigen was a large glycoprotein. the glycoprotein was purified partially by Sephadex ultrafiltration. and almost completely by affinity chromatography on a concanavalin A-Sepharose column.