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: 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.

Notes: 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.

Notes: 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.

Notes: 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.

Notes: 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.

Notes: 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.

Notes: 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.

Notes: 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.

Notes: 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.

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: Chlamydodon pedarius has peculiar and interesting cytoplasmic organelles, such as the pharyngeal basket and the cross-striped band, and exhibits plasmotomy of an uncommon type at the division stage. For comparison of the results of observations on fixed and stained material and on living material examined with phase contrast, and because of finding important differences in such a comparison, this morphological study of the cytoplasmic organelles was undertaken.The cilia, arranged in about forty rows only on the ventral surface, the anterior part of which shifts out of the dorsal body, bending to the dorsal side, are almost the same everywhere, about 5 μ in length. The cross-striped band, encircling the body surface so as to divide it into dorsal and ventral parts, has the power of movement, such as folding of the semicircular trichites and closing or opening of them. The oral apparatus, composed of a membranous system and a pharyngeal basket, is an elaborate organelle. The membranous system shows such movement as seen in a sphincter muscle, moving the triangular trichites in a manner which opens or closes the cytostome. Each of the triangular trichites is con nected with the expanded end of a long trichite; together these structures. 11–13 in number, constitute the pharyngeal basket. The ridges, the long trichites and the semicircular trichites are composed of fibrillar elements, but their twisted figures may be produced artificially by staining methods.Binary fission of Chlamydodon pedarius, under natural conditions in the season from April to October, occurs daily during the period 11 a.m. to 4 p.m. Each of the fissions takes about 2 hours. In the first half of this fission time: the V-area consisting of four central ciliary systems gives rise to transitions in the arrangement of the ciliary rows and ridges on both its anterior and middle portions; the pharyngeal basket falls down into the cytoplasm; and rosettes appear in the above two fields. On the other hand, plasmotomy arises in a fission furrow from the right side of the fission line. In the second half of the fission process, the oral apparatuses develop from the rosettes, while the old basket is dissolved into the cytoplasm; and, as the fission furrow extends leftward, two transverse bands and the frontal pellicle of the posterior daughter ciliate are organized on the surface of the fission furrow.

Notes: The centrioles of Trichonympha from termites do not differ, either in structure or function, from those of Trichonympha in Crypiocercus. The previous claims of a difference are erroneous. The roles of the centrioles in the reproduction of new extranuclear organelles and in nuclear duplication are described. The centrioles are autonomous organdies. They are just as essential for a cell's existence as are chromosomes.

Notes: A survey of protozoa was made from twelve varied sites in the region of the Mountain Lake atop Salt Pond Mountain, about 8 direct miles NNW of Newport, in Giles County, Virginia. Identifications for these sites and for 6 others previously sampled by other investigators which are recorded in unpublished reports are included. Species identified total 576; in 243 other instances genus is identified, but not species. Organisms seen but not identified to generic level are omitted. One hundred fifty-one mastigophoran species are listed; with 101 instances of generic, but not specific identification being made. Of these 102 are phytomastigophorean species; and generic placements 77 times are also listed. Seven orders, 7 suborders and 49 genera are represented. Forty-nine zoomastigophorean species are noted; and 24 other times a genus was identified. Five orders, two suborders, 18 families and 35 genera are included. Eighty-one species of sarcodina are noted. Seventy-four of these are rhizopods, and 7, actinopods. Genus, but not species was established for certain sarcodina in 52 instances. Three orders, 10 suborders, 13 families and 44 genera are represented. Ciliophora, including opalinids and suctorians, number 144 species in this list. Three are opalinds, and 141 (including the suctorians) are euciliates. In 88 observations, genus, but not species of ciliophorans was identified. Two classes, two subclasses, 11 orders, 8 suborders, 43 families and 97 genera are included. Two sporozoa are included, being unidentified species of the telosporidian genus Eimeri a, and the sarcosporidian genus, SarcocystisSome data are given relative to the nature of the sites of collection. The restricted distribution of certain organisms in certain habitats is discussed. The sites are geographically located by altitude, latitude and longitude, as well as on a map of the region.Many other protozoa are undoubtedly present in the area, the ubiquity of many protozoa being well-known. Little has been done to survey parasitic species, and other studies should later reveal more of the free-living ones.

Notes: Three strains of Hypotrichomonas acosta were isolated in axenic culture. Attempts to develop a defined medium directly from a defined medium suitable for Tetrahymena pyriformis were unsuccessful. Development of partly defined media by substitution for undefined materials in Diamond's medium were more successful. Horse serum was replaced by 1 mg. % TEM-4T (a diacetyl tartaric acid ester of monoglycerides from tallow) and 0.5 mg.% cholesterol. Yeast extract was replaced by a mixture of ribonucleotides. Inclusion of several additional components permitted reducing the Trypticase concentration from 2% to 0.25%.

Notes: An amoeba found on the fresh-water medusa, Craspedacusta sowerbii Lankester, collected in the Southampton Quarry Pond at Richmond, Virginia, is described and found to be identical with Hydramoeba hydroxena (Entz) which occurs on various species of fresh-water hydras. Transfer of the amoeba to Hydra cauliculata Hyman, and other experiments, show it to be a facultative parasite for this species. The pathogenicity of the amoeba is decreased by fouling of the culture medium; the resistance of the hydra is decreased by starvation. Hydramoeba is also capable of destroying adult fresh-water medusae in six days. Its relation to young medusae is not known, but the amoeba apparently does not attack the polyps or other developmental stages.

Notes: A Tritrichomonas foetus-likt flagellate was found in the stomach, small intestine, and cecum as well as in the nasal cavity of pigs. Xo appreciable differences in morphology or response to cultivation could be found among the trichomonads from the different sites; therefore, it is considered that they.belong to a single species, Tritrichomonas suis (Gruby & Delafond). a description of which is given. This organism could be grown indefinitely in various media, and, after a short period of cultivation, it was the only species surviving in cultures that originated from cecal samples containing 2 or 3 species. T. suis was found in the nasal cavity in 55 of 100 pigs, in the stomach in 41 (8.0%) of 512, in the small intestine in 3 of 100. and in the cecum in 215 (43.370) of 496. A T. batrachorum-type trichomonad, herein described as Tritrichomonas rotunda n. sp., was found in the cecum in 52 (10.5%) of 496 pigs. This species is typically broadly pyriform or rotund (average length 8.95 ± 0.83 ii, range, 6.83-11.4), with 3 equal or subequal anterior flagella slightly longer than the body, a relatively low undulating membrane extending y2 to 2/1 of the length of the body, and a posterior free flagellum usually a little shorter than the body. The narrow axostyle, expanded anteriorly into a curved capitulum closely associated with the large, spherical, anteriorly located nucleus, projects from the posterior surface of the flagellate for a distance which equals about 2/3 half of the body length. The parabasal apparatus is biramus. This species could be maintained only temporarily in media not containing extracts of cecal contents. A Trichomonas pronazeki-typt flagellate, found in the cecum in 126 (25.4%) of 496 pigs and in the small intestine in 1 of 100. is described as Trichomonas buttreyi n. sp. This organism is relatively small (average length 5.92 ± 0.79 μ, range 4.55-7.49). ellipsoidal in shape, with 5 to 4 flagella up to twice as long as the body, a relatively high undulating membrane of body length, a narrow axostyle with an inconspicuous capitulum closely associated with the usually oval nucleus, a projecting part of the axostyle that equals about j; of the body length, and a disc-shaped parabasal body lying dorso-lateral to the nucleus. In media without cecal extract this species could not be subcultured.

Notes: Actinosphaerium nucleofilum has been studied by light and electron microscopy. Thin sections of this organism reveal the relatively compact endoplasm to consist of numerous vacuoles and mitochondria. Scattered in the cytoplasm are dense particles, presumably ribonucleoprotein particles, endoplasmic reticulum of the rough variety and a tubular endoplasmic reticulum of the smooth variety. The many nucleido not appear to be randomly scattered in the cytoplasm but rather to be arranged in a circular pattern. Each is bounded by a double membrane envelope. A Golgi complex, consisting of isolated bodies with an ultrastructure similar to that described by others, is usually seen associated with each nucleus.The ectoplasm contains many vacuoles of varying diameter, each of which is limited by a thin membrane; vacuoles containing dense granular material, and mitochondria.The radially arranged axiopodia are extensions of the ectoplasm. The periphery is largely composed of vacuoles, some of which contain dense granules, and mitochondria. The axial rod is birefringent and consists of many fine filaments oriented parallel to the longitudinal axis of the axiopodium. The constituent filaments penetrate deep into the endoplasm where they end in the vicinity of nuclei. The fibrillar component of the axiopodia may represent contractile units.

Notes: Bresslaua vorax is a dimorphic ciliate with micro-stome and macrostome forms. The development of the macro-stome form is associated with pronounced extension of the vestibule and vestibular opening and gross torsion of the ciliate which finally shows little resemblance to the microstome form. These transformations culminate a phylogenetic trend in the Colpodidae which can be followed from the ciliates of relatively simple structure, such as Woodruffia, through Bryophrya, Colpoda and Tillina to Bresslaua. This phylogenetic trend is marked by the increasing importance of stomatogenesis. The morphogenetic pattern of these transformations appears to distinguish the Colpodidae from other trichostomatous ciliates, such as the Plagiopylidae.

Notes: Epistylis caldwelli n.sp., a β-mesosaprobic epi-biont, was collected from the surface zone of only two of 164 water bodies at Singapore. It is recorded from the neustonic mosquito larvae Anopheles (Anophele s) hyrcanus Pallas subsp., An. (Myzomyia) kochi Donitz and Culex (Lutzi a) fuscanus Wiedemann, also from corixids, Micronecta quadristrigata Bred-din, copepods, Mesocyclops leuckarti aequatorialis Kiefer, and floating dragonfly exuviae. Subsurface and benthic organisms were not infested. The squat zooids (av, 57.6 ± 34.8 μwhen fully extended) have a median contractile vacuole and a long and sinuous macronucleus. Colonies consist of 2–16 individuals on a short and unusually massive stalk up to 50 μthick.

Notes: Three new species of Caryospora (Coccidiida, Eimeriidae) are described from Psammophis sibilans phillipsi. These are C. psammophi sp. nov.: oöcysts with yellow walls, 25 to 34 μ. ×23 to 31 μ C. hermae sp. nov.: oöcysts with colorless walls, 21 to 24 μ× 20 to 22 p) and C. weyerae sp. nov.: oocysts with colorless walls, 14 to 18 μ× 13 to 17 μ, Endogenous stages of all three parasites are found in epithelial cells of the small intestine of the snake.A Caryospora from Israel is described and named C. zucker-manae sp. nov.: oöcysts spherical with outer wall crumpled. 15 to 18 μ

Notes: Cultures of tissues from ducks infected with Plasmodium elongatum supported the growth and development of the parasites for 72 hours. Cultured parasites exhibited the same properties when reintroduced into the vertebrate host as did cells derived from similar sources upon direct transfer into a new bird. Parasites derived from acute infections led to patent infections after an incubation period of 7–8 days. Parasites derived from latent infections gave rise to infections becoming apparent after 11–15 days. Results of dilution experiments show that this lag period is not due to low numbers of parasites contained in tissues from latent infections. It is concluded that invaded cells may, after the acute stage of the infection, elaborate some hypothetical inhibitor which arrests multiplication of the parasite, while not interfering with its viability or virulence.

Notes: Entamoeba invadens was studied in 8 species of snakes at temperatures of 13–14° and 25°C. Infected snakes of all species failed to show any gross pathology at 13°C, although amoebae were isolated from the snakes by culture. At the higher temperature all species showed pathological changes, most severe in Natrix, dekayi and red belly, and progressively less severe in the garter, milk, ribbon, ringneck and green snakes. For the last S species, the pathology in the liver and intestine was so characteristic as to provide an adequate basis for identification of the snake. Snakes infected at the lower temperature and later transferred to 25° showed the same pathological changes as those kept at 25° throughout. The possible effects of behavior patterns of snakes on pathogenicity of the amoebae are pointed out.

Notes: Hypotrichomonas gen nov., with a feeble undulating membrane but lacking a costa, is placed in the family Monocercomonadidae Kirby of the order Trichomonadida Kirby. H. acosta (Moskowitz) from squamate reptiles is designated as the type species. It has 3 unequal anterior flagella. The proximal part of its recurrent flagellum is attached to the surface of the body along an accessory filament. A low membrane with typically a few undulations extends between the accessory filament and the body surface. The membrane, which varies greatly in length in relation to the length of the body among strains of the species, is not supported by a costa. The recurrent flagellum continues as a free posterior flagellum beyond the end of the undulating membrane and terminates in an acroneme. The capitulum of the axostyle, spatulate or scoop-shaped, is closely applied to the anteriorly located nucleus. The capitulum extends anteriorly into a crescent-shaped pelta. The relatively stout trunk of the axostyle is straight or twisted. It projects for some distance from the posterior body surface, and the terminal segment of the projecting part tapers gradually to a point. The parabasal apparatus consists of a rod- or shaped body and of a filament or filaments.In division, the full complement of flagella in each of the mastigonts is restored relatively late during division but before cytokinesis. One of the daughter individuals retains the parental undulating membrane; the other develops a new organelle. The development of the new membrane is first marked by the appearance of an acroneme, presumably recurrent flagellum, early in division. The proximal part of this flagellum becomes progressively attached to the body surface. The process of attachment is paralleled by differentiation of the accessory filament and is followed by the appearance of the undulating membrane. The parental axostyle is resorbed during division, and each daughter individual develops this organelle de wove. In the very early stages of division the parabasal consisted of two arms and in all more advanced stages of a single rod-shaped body applied to a single filament.The significance of Hypotrichonionas in the evolution of trichomonads is discussed. Its morphology and morphogenesis suggest that this genus may represent an important step in the evolution of Trichomonadidae from Monocercomonadidae.

Notes: Two new species of Eimeria, E. megaresidua and E. longaspora, are described from the common American newt, Notopthalmus viridescens. The hosts were from the vicinity of Douglas Lake in Northern Michigan. Observations of timeof sporulation of the oocyst relative to host defecation and possible significance of the seasonal distribution of the parasites are discussed.

Notes: Plasmodium minasense Carini and Rudolph is recorded from three of 28 examples of Gonyocephalus bor-neensis (Schlegel) from Kepong and Bukit Lagong, Selangor, and P. vastator n. sp. is described from a single example of Draco volans Gray from Ulu Langat, Selangor. Both of these arboreal agamid lizards are new hosts for malaria parasites.P. vastator n. sp. is characterized by its highly amoeboid trophozoites, nucleophilic schizonts producing from four to eight (usually six) merozoites, and large (up to 22.1 ± 8.1 μ) gametocytes which alter and ultimately destroy the host cell. Forty-six other lizards of nine species, and 28 snakes of 11 species, proved negative for Plasmodium,

Notes: An X-ray induced mutant (S-16) of Chlamydomonas moewusii Gerloff lacked observable contractile vacuoles. Unlike the wild strain with vacuoles, S-16 survived only when the osmotic pressure of the medium was above 1.5 atmospheres and was provided by compounds that penetrate cell membranes slowly, like NaCl or sucrose. In solutions of such compounds, when the osmotic pressure was above 2.1 atmospheres, growth of S-16 was similar to that of the wild strain. S-16 did not grow at all in isosmotic solutions of ethylene glycol cr other rapidly penetrating compounds. Urea and glycerol, which penetrate only moderately rapidly, allowed an intermediate growth. Thus, S-16 cells are dependent upon the prevention of net inward diffusion of water.Contractile vacuoles of the wild strain were not seen when cells were suspended in solutions that allowed growth of S-16. but were visible in isosmotic solutions cf ethylene glycol or ethanol. S-16 cells ultimately burst in solutions of low osmotic pressure; large vacuole-like areas were formed but did not contract.The pulsation rate of vacuoles of the wild strain was relatively independent of osmetic pressure; vacuoles became smaller and finally invisible at higher osmotic pressures.It is concluded that the sole essential function of contractile vacuoles in C. moewusii is elimination of water.

Notes: The purification procedure for native deoxyribonucleic acid (DNA) from the green alga Chlamydomonas reinhardi is described, using a modified detergent lysis, salt extractions, and alcohol precipitations. A tracer experiment with the addition of a bacterial transforming principle from Hemophilus influenzae demonstrated a recovery of mere than 30% of the bacterial transforming principle in an extensively purified DNA preparation.

Notes: For development of flagella by myxamoebae of the true slime mold, Didymium nigripes, optimal results were obtained when they were incubated in 0.05 M NaHCOa (pH 9.1). Streptomycin inhibited flagella formation in pH 6.2 phosphate buffer but had no effect in NaHC03. The time necessary for 50% of the population of myxamoebae to become flagellated was independent of the concentration of myxamoebae; hence, the morphogenesis probably follows first-order kinetics. The acquisition of flagella was divisible into 4 stages by means of time-lapse cinephotomicroscopy: an ameboid stage, a stage of morphogenesis, an ameboid-flagellate stage, and a free-swimming flagellate stage. At least 90% of the population developed flagella within 60 min. under optimal conditions. The flagellar apparatus consists of a long and a short flagellum, each arising from a granule in the blepharo-plast. The blepharoplast is connected to the nucleus by a rhizoplast.

Notes: In order to study the blepharoplast-kinetoplast region in the adult form of Schizotrypanum cruzi thin sections of this form, obtained in tissue cultures, have been examined with the electron microscope. It has been seen that the kinetoplast is contained in a large spherical, vacuole-like space, in hich its osmiophilic mass is more dispersed than in the leishmania and crithidia forms, where it is contained in a rectangular, almost linear space. The basal body of the flagellum has been found at the margin of the vacuole, although separated from it. A group of striae in parallel array has been found with regularity in all the trypanosome forms, similar to the structures of the parabasal body in other protozoa, or to the Golgi apparatus of metazoan cells. The significance of this structure for the parasite is discussed.

Notes: Endogenous respiration and respiration in the presence of glucose of the culture forms of Endotrypanum schaudinni, Leishmania enriettü, Schizotrypanum vespertilionis, and S. cruzi, have been compared in terms of cell number and nitrogen content. Growth curves for the 4 species at 26° C. showed that E. schaudinni and L. enriettü grow faster than the Schizotrypanum in a reproducible modification of Senekjie's diphasic medium. Respiration was studied manometrically using organisms harvested in the exponential phase of growth. Res-piratory patterns at 30° C. and pH 7.2 are presented for each species. Low endogenous rates are characteristic of E. schaudinni and L. enriettii; they are relatively high in both Schizotrypanum spp. The respiration of E. schaudinni is stimulated from 5.3 to 36.1 times by glucose; that of L. enriettii from 5.2 to 9.7 times and that of the Schizotrypanum from 1.9 to 5.7 times. Carbohydrate is of great importance for the survival and motility of E. schaudinni and L. enriettii, but plays a relatively minor role in Schizotrypanum.

Notes: A study was made of the effects of solar radiation, temperature, relative humidity, centrifugation, oxygen, pH, and certain chemical agents on the sporulation of oocysts of Eimeria zurnii of cattle. Of various chemical agents and bactericides tested, only HgCl2 exhibited a high level of activity against unsporulated oocysts. Extreme pH values of 1 and 13 did not alter sporulation. Oocysts required at least 10% of the normal amount of oxygen to sporulate at a normal rate. Physical factors found to be lethal for E. zurnii were: sunlight for as short a time as 4 hours, drying at 25% or less relative humidity, and freezing below about -7° C. Survival was directly proportional to relative humidity, but within the limits of the observations reported here, there was no correlation with time or temperature. Normal sporulation occurred from about 8° up to 32.5° C. Below 12° the time required for sporulation was exceedingly long, and at 35° sporulation was morphologically abnormal. The optimal temperature for sporulation was about 30° at which temperature some organisms completed the process in 23 hours. Fifty % of the oocysts required 65 hours to begin sporulating at 20° and 36 hours at 25° C.

Notes: Dimorphic populations of Tetrahymena patula L-FF result when this organism is grown axenically in Loefer's medium supplemented with aqueous lettuce extract. The two different cell types in these cultures are identified as “macrostomes”and “microstomes.” Isolation of microstomes and macrostomes from the dimorphic cultures has shown that both cell types reproduce by binary fission in this medium, and further that each cell type will occasionally give rise to the other under these conditions. Isolation experiments have also shown that both microstomes and macrostomes from the dimorphic cultures are capable of giving rise to the reproductive cyst. The cells which are liberated from the cyst have small mouths but are best referred to as “tomites,” in order to distinguish them from the self-perpetuating microstomes described above. The relatively small, rapidly swimming tomites will either transform into macrostomes or reproduce as microstomes. The life histoy of T. patula thus consists of three cell types as follows, each capable of giving rise to the other two: a macrostome, a microstome, and a tomite. Silver preparations of the dimorphic cultures have shown that oral replacement takes place. This consists of resorption of the oral apparatus and its replacement by differentiation of new mouth parts from an anarchic field of kinetosomes which arises immediately posterior to the old oral apparatus. It is suggested that this process is involved in the macrostome-microstome interconversions.Growth curves were determined for T. patula feeding on a variety of substrates. These data indicate that this species is extremely well adapted as a carnivore. It grows very poorly on bacteria, but will grow well in axenic culture if aqueous lettuce extract is provided. The lettuce extract greatly reduces the generation time and increases the maximum cell density.Loss of the micronucleus in stain L-FF is reported and discussed. The loss may be an indication that this strain has entered the senile phase of the Maupasian life cycle.

Notes: A method is described whereby large amounts of Euglena cells can be obtained efficiently for enzymological studies. A completely defined, low pH medium which offers relative freedom from contamination is usee The cuh re-equipment is also usable for the mass culture of many other unicellular algae.

Notes: Thecamoeba sphaeronucleolus, and other verrucosid amebas with thick, pellicular ectoplasm, which live in moist soil, can identify the presence of testate rhizopodal prey at distances of 20 to 30 μ, possibly chemotactically or rheotacti-caliy. Prey is seized by extension of a pseudopod towards it, and adhesion of the pellicular pseudopodal tip to the prey upon contact. Ingestion is accomplished by conversion of the pellicular coat of the pseudopod into an ingestive tube via digestion of the pellicular tip and the withdrawal of the endoplasm within, causing suction. The prey is drawn into the tube and enclosed therein; and is then drawn down the pseudopodal tube and into a food cup, which closes around the prey to form a food vacuole. Flagellate prey is identified by its movements nearby, and is seized by adhesion of the extended pseadopod to a flagellum. The flagellum is drawn through a tiny hole digested by the ameba through the pellicle of its psendopod. is seized by and drawn into the granular endoplasm. The body of the flagellate is drawn after it into a food vscuoie in the endoplasm. Suction applied to the flagellum appears to exert the necessary force to draw the flagellate in. The movements involved are related to, but not synonymous with, those of locomotion and appear to be complex biochemical and biophysical interactions not explainable by present theories of protoplasmic movements.

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: Using the mite Dermanyssus gallinae as the vector and the canary (Serinus canariu s) as the avian host, the author was able to demonstrate the transmission of the parasite Lankesterella (=Atoxoplasm a) garnhami Lainson, 1959. Mites were taken from infected canaries and fed to clean ones; 3 out of 4 birds became infected. Mites taken from infected sparrows (Passer domesticus domesticu s) were fed to 4 other clean canaries, all of which became infected. Natural transmission of the parasite was achieved when 2 clean canaries were exposed to infestation by mites which had previously fed exclusively on infected sparrows. Six control canaries, obtained from the same source as the experimental birds, were all shown to be uninfected. It is concluded that the parasites in the sparrow and the canary are identical. The specific name of Lankesterella serini Lainson, 1959, for the organism in the canary becomes, therefore, a synonym of L. garnhami Lainson, 1959.

Notes: The techniques of silver impregnation and of digitonin solubilization have been applied to an investigation of aspects of cortical morphogenesis in Glaucoma chattoni. The typical stages of the formation of new oral areas (stomato-genesis), as well as of other related surface events, are described in detail. Estimates were made of the relative and absolute durations of these stages; these estimates indicate that for animals growing at 25°C. in bacterized culture, stomatogenesis and cell division together occupy about one third of the division cycle.Certain atypical morphogenetic phenomena have been encountered and are briefly described. These include three cases of stomatogenesis along a kinety other than kinety 1, several instances of anterior stomatogenesis leading to replacement of existing oral areas, and numerous cases of spontaneous loss of oral areas.Finally, the process of increase in number of kinetosomes along certain kineties has been submitted to intensive study. It has been found that comparatively little increase takes place during stomatogenesis and cell division; the bulk of kinetosomal increase along the kineties takes place during the first two-thirds of the division cycle. Data relevant to this increase have been analyzed according to the method of Scherbaum & Rasch; this analysis reveals that the probable phases of most rapid kinetosomal increase, along kinety l at least, occur just after division, and just before the beginning of stomatogenesis.

Notes: Certain polyoxyethylene ethers, derived from p-tert.-octylphenol and representatives of series which have activity against murine tuberculosis and leprosy were tested in several protozoal infections. Triton WR-1339 represented the series in which the phenolic groups are arranged linearly while HOC-12½ and LOC-60 represented series in which the phenolic groups were condensed into a cyclic structure. WR-1339 was found to be active against infections with Trypanosoma gambiense, T. rhodesiense, T. brucei, T. congolense, and T. equipevdum in mice, and against Leishmania donovani in the golden hamster. The “macrocyclic” HOC-12:4 also had activity, but of a much lower order, against the first three trypanosome infections listed, and in leishmaniasis it had activity equivalent to that of WR-1339. Neither of these compounds was active against Trypanosoma cruzi, Plasmodium berghei nor Toxoplasma gondii in mice, nor against Leptospira icterohemorrhagiae in guinea pigs. The other macrocyclic compound, LOC-60, was inactive in the infections in which it was tested (T. congolense and T. rhodesiense).Although the action of the polyoxyethylene hers in murine tuberculosis and leprosy had been reported to be an indirect one, affecting the host rather than the mycobacteria (which are said to be resistant to these materials in vitro) it was found that the differential effects in trypanosomiasis, observed with WR-1339 (which had good activity in vivo) and HOC-12½ (which had poor activity in v i v o), were well correlated with their effects in vitro. In the light of the strength of the dilutions which killed T. congolense in the t a t tube and the blood levels of WR-1339 obtaining after medication the control of the infection could be attributed to the direct action of the compound on the parasite although some indirect effect on the host, perhaps of the nature of reticulo-endothelial stimulation, could not be excluded.

Notes: The use of saponin hemolysis, buffer washings and deoxyribonuclease yields quantities of erythrocyte-free plasmodia sufficiently pure for physico-chemical studies. The pigment produced by Plasmodium lophurae, unlike the pigments of the simian and human malarias, is of such low solubility in buffer solutions that urea is necessary as an additive to the buffer for adequate solubilization. On the basis of spectral and electrophoretic qualities, the pigment is a protein-porphyrin complex closely resembling methemoglobin but clearly distinct from hematin. Extraction of the pigment in solvents which degrade hemoglobin, e.g. phenol, 0.1 N NaOH, cannot be used to ascertain the properties of hemozoin, for the pigment in such solvents shows a spectrum identical to hemoglobin.The soluble parasite proteins which constitute approximately 55% of the totaI volume of the parasite as revealed by electrophoretic and ultracentrifugal analysis appear to be homogeneous. They show a marked similarity to the host hemoglobin, but differ sufficiently to verify their integrity and individuality.

Notes: Stomatogenesis in Paramecium aurelia is shown to involve the lower kineties of the right vestibular wall, the endoral membrane and perhaps the quadrulus. The anarchic field for the new buccal organelles is formed by granules produced from somatic kinetosomes of the right vestibular wall. The endoral membrane becomes incorporated into the buccal anlage and probably regulates orientation and development of the new organelles. A production of heretofore unobserved buccal kinetosomes from the quadrulus is described and it is suggested that these may form the new endoral membrane for the proter.During conjugation the infraciliature dedifferentiates in the area of fusion between the conjugants. The buccal organelles dedifferentiate at the time of pronucleus formation and transfer. It is suggested that dedifferentiation of structures in the fusion area is caused by a partial solation of the cortex in this area. The dedifferentiation of the buccal organelles results from the solation of the cytoplasm and the cortex of the paroral cone during pronucleus migration. The redifferentiation of the buccal organelles and somatic kinetosomes is suggested to be a recrystallization or gelation of the cortex with the structures re-forming in their normal positions and not from an anarchic field as at fission.

Notes: When exogenous ecdysone is injected into a host (adult or intermolt nymph) which has no ecdysone of its own, gametogenesis is induced in the protozoa of such a host, although the host itself never undergoes ecdysis. The time required to induce this sexual process varies in different genera and with the dosage of hormone administered; but it is never possible, regardless of the amount of hormone given, to induce gametogenesis in all the genera at the same time; some still begin a day or two later than others, but never 40-45 days later as occurs in untreated roaches.Likewise, when exogenous ecdysone is administered to a nymphal host in the molting period, the sexual cycles of its protozoa are greatly accelerated, and the host undergoes ecdy-sis much sooner than would otherwise have been the case. Both sexuality in the protozoa and the molting process in the host are accelerated. Only when large doses of ecdysone are administered are the sexual cycles of the protozoa modified in any way except a decided acceleration. Quite large amounts of ecdysone present special problems for the protozoa, problems they never encounter in nature. The growth and differentiation hormone ecdysone causes the protozoa to grow and differentiate so rapidly that many of them cannot keep pace; as a result, degeneration begins, and death follows. But this over-acceleration effect of ecdysone and death of the protozoa occurs only in those genera which have not undergone gametogenesis when the large amount of hormone is administered; those which have completed gametogenesis are not affected at all. The results of acceleration have been observed in most genera, but have been studied more intensively in Tricho-nympha, where they are usually seen to be considerably more pronounced on the nuclei and chromosomes than on the cytoplasm. As a result, this genus, which invariably in nature undergoes only fertilization, is sometimes made to undergo either autogamy or endomitosis. The pronuclei, for example, differentiate and are ready to (and do) fuse before the cytoplasm of the gametocyte divides to form gametes. In the case of endomitosis, precocious differentiation of chromosomes seems to produce, or at least goes along with, premature degeneration of one centriole, the one that would ordinarily degenerate following fusion of gametes. Thus, nuclear division is made impossible.In some genera of the protozoa, the ecdysone titer must drop greatly before meiosis can begin. If the titer, after ecdysis. when it normally drops precipitously, is kept high with injections, meiosis does not begin; it is retarded for as long as the ecdysone titer is kept high.

Notes: Over ninety genera of ciliated protozoa have been given names preoccupied by the generic names of other animal organisms. To date some sixty of these junior homonyms never have been corrected. In half of these cases the homonymous ciliate names have been buried as synonyms of one kind or another, however, and need be of no further practical concern. For the remaining genera, thirty in number, replacement names arc proposed in the present paper in accordance with provisions of the International Rules of Zoological Nomenclature. Such action is considered to be in the best interest of ultimate taxonomic stability among the groups of organisms involved. New names also have had to be proposed for five families or subfamilies whose type genera have lost their original names through homonymy.

Notes: Paramecia, in a nearly defined axenic medium, require a specific fatty acid and a “protein” factor for growth and survival. The fatty acid requirement was readily satisfied by stearic acid or oleic acid. The saturated acids, arachidic (C20) and one preparation of palmitic (C16), had lower growth activity than did stearic acid. The unsaturated fatty acids palmitoleic (C16Δ9), linoleic (C18Δ9,12), linolenic (C18Δ9,12,15), and arachidonir (C20Δ5,8,11,14) and the saturated fatty acids of C14 through C6. myristic, lauric, capric, caprylic and caproic, were inactive. A few other fatty acid-containing compounds. i.e., esters, were also tested for growth-promoting activity, with concordant results.The “protein” factor has not been completely characterized; a nondialyzable protein-containing fraction from yeast or crystalline ovalbumin provided it. Hydrolysis products of these substances were inactive. A possible role of the ovalbumin as a carrier for fatty acids is discussed.

Notes: The kinetoplast and associated structures in Leishmanial tropica, Trypanosoma cruzi, T. lewisi, Herpeto-inonas culicis, H. muscarum and Crithidia fasciculata have been studied by electron microscopy of thin sections. The kinetoplast appears as a mitochondrion within which are antero-posteriorly oriented anastomosing fibers. In the three species parasitic in vertebrates there is a sharply delimited anterior zone where these fibers are thick and electron-dense. In the insect parasites the fibers form a looser network of approximately uniform density from anterior to posterior.The blepharoplast is the 9-fibered cylinder forming the base of the axoneme and extending below the base of the reservoir. A diffuse mass of electron-dense material surrounding this is the basal granule, visible also with the light microscope.The contractile vacuole appears in electron microsraphs as a clear area associated with Golgi material.

Notes: Stages in the life-cycle of the coccidium Eimeria neosciuri Prasad(12), from the epithelial lining of the small intestine of Sciurus carolinensis Gmelin are described, with particular reference to the endogenous phases. The pathology, sporulation and rate of oocyst production are determined, and a discussion on known coccidia from related Sciurus spec: included.

Notes: A study by means of paper electrophoresis of the scrum.proteins and lipoproteins during the course of infection of chicks with Plasmodium lophurae, reveals a qualitative change in the gamma-globulin and demonstrates: a significant crisis period depression of the albumin; no alteration of the alpha-globulin or alpha-lipoprotein; a significant crisis period rise in the beta- and gamma-g'obuiins with the former persisting in higher amounts well after the crisis of the infection. The significance of such changes with reference to previous work and the induced pathology is discussed.

Notes: Thin sections of Plasmodium, cathemerium obtained 3 to 10 days after ingestion of blood by mosquitoes were examined by electron microscopy. Oocysts are encased in a relatively thick structureless capsule which becomes progressively thinner with advancing age and completely disappears in places at the time of release of the sporozoites. The capsule blends with and in most cases cannot be distinguished from the “elastic” layer of the mosquito stomach. For this reason the capsule is tentatively regarded as a product of the host rather than of the parasite. Capsular material appears to be shed into the interior of the oocyst and may serve as nutrient material in the later stages of development. Oöcysts and sporozoites contain mitochondria, endoplasmic reticulum and nuclei with nucleoli at all stages examined.All limiting membranes within the oocyst are feebly developed and no cell boundaries are seen until the sporozoites begin to form. At this stage, the sporozoites acquire very prominent surface membranes which are retained by the mature forms.Sporozoites contain long rods and cylinders of homogeneous material of moderate density. Their functional significance is not understood.

Notes: Hysterocineta eiseniae, from the oligochaete Ei-senia lonnbergi, and Ptychostomum campelomae sp. nov., from the fresh-water prosobranch snail Campeloma geniculum, have been studied primarily with a view to arriving at a better understanding; of the adoral and buccal ciliature of hystero-cinetid ciliates. In both of these species (as well as in representatives of two undescribed genera), the arrangement of adoral and buccal ciliary organelles is fundamentally the same. There are three adoral rows of cilia extending transversely across the posterior end of the body, toward the buccal cavity. The row nearest the superior surface consists of cilia which are fused into a hyaline and relatively inactive membrane. This row enters the buccal cavity on its left side and extends inward to the cytostome. The other two rows, inferior to the membrane, are close together and consist of active and coherent cilia which collectively form a brush-like complex. Oi these rows, the one nearer to the membrane enters the buccal cavity on its right side. The other row ends at the right side of the buccal overture, and near the point where it terminates, but on the opposite side of the continuous row, a similar series of cilia originates and closely parallels the continuous row to the cytostome.The diagnosis of the family Hysterocinetidae is emended on the basis of this characteristic arrangement of the adoral and buccal ciliature. The hysterocinetids appear to be rather closely related to ciliates of the family Hemispeiridae, and are therefore tentatively referred to the order Thigmotrichida.

Notes: 3-Amino-l,2,4-triazole (AT) stops multiplication of the photosynthetic protists, Ochromonas danica, O. mal-hamensis, Euglena gracilis var. bacillaris. and Rhodopseudo-monas palustris; it also stops growth of the multicellular plant, Spirodela oligorhiza. O. danica and S. oligorhiza are the most sensitive. AT is about equally inhibitory to algal flagellates grown in the light or dark. Porphyrin biosynthesis is suggested as the probable site of inhibition by AT. Both AT and streptomycin (SM) bleach all the above organisms. Bleaching is permanent only in SM-bleached E. gracilis; all the other organisms become fully pigmented when placed in inhibitor-free media. The uniqueness of the SM-bkaching of E. gracilis is discussed.

Notes: Food vacuoles have been studied in various stages of the digestive process in cultures of Pelomyxa carolinensis and P. illinoisensis after feeding Tetrahymena and Paramecium. The vacuole wall formed immediately after capture of the food organism may be only 100 m/i thick. The changes observed in the food organisms indicate that first the membranes of the pellicle are ruptured, then mitochondria, cytoplasmic matrix, and nucleus are attacked; cilia and trichocysts are more resistant. The food vacuole membrane is involved first in the removal of water from the vacuole, then in transfer of cytoplasmic fluid into the vacuole, and finally in removal of digestion products from ihe vacuole by pinocyt. Vesicles which have been derived from the plasnulf—a b pinocytosis have been observed. They characteristically have a non-turgid, non-spherical appearance when located deep m the cytoplasm and are stainable with phosphotungstic acid. Pinocytosis and the function of food vacuole membranes are discussed. It is concluded that at leait two factors contribute to the benefits derived by amoebae from pinocytosis: (1) modification of the plasmalemma membrane near the time when it becomes the pinocytic vesicle membrane, and (2) increased surface area for diffusion.

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.