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: SUMMARY. The mating behavior of 16 stocks of Paramecium multimicronucleatum from 12 states has been studied. Mating always follows a decline in nutritive conditions. The evidence indicates that there exists one set of four interbreeding mating types. The period of subculture strongly influences the mating reactions, many stocks mating only long after isolation from nature and culture in the laboratory under the restricted conditions employed. Selfing was observed to occur in many races, usually after long periods of subculture. It first occurred in only a small proportion of the population, later in a larger proportion. The similarities and differences between P. multimicronucleatum and other species of protozoa showing multiple mating types are discussed.

Notes: SUMMARY. A study of the temperature-pressure relationship in oxygen poisoning of Paramecium caudatum was undertaken, as the initial step in defining some of the major factors in in vivo oxygen poisoning. Paramecium was selected because it was relatively simple to culture in a pureline clone, large numbers were readily obtained, and it was large enough to be clearly visible under low magnification. The protozoa were exposed to oxygen pressures of 0 (100%), 15, 30, 45, 60, 75, 90, 105, 120 pounds/inch2 gauge pressure at each of the following temperatures: 1, 5, 10, 15, 20, and 27°C. Exposure was accomplished in a transparent, high-pressure lucite tank which permitted visual observation with aid of a dissecting microscope. It was found at temperatures above 5°C. that oxygen toxicity varied directly with pressure, but below this temperature, with oxygen tensions of 1–2 atmospheres (absolute), oxygen toxicity varied inversely as the temperature. The possibility is advanced that oxygen may be affecting two cellular processes (perhaps enzymatic), one of which is temperature-limited below 5°C. and would, therefore, decrease the death time as the temperature is decreased. Several experiments performed at 3°C. produced a death time intermediate between results obtained at 1° and 5°C.

Notes: SUMMARY. A stock of Paramecium bursaria is described in which the peniculus contains only 8 columns of cilia and associated “granules”. The gullet system is composed of organelle complexes almost exclusively, and incorporates no underlying or transecting extensions of “pellicular fibrillar systems”. A brief discussion is presented on the value of the peniculus as a taxonomic criterion in separating “aurelia” and “bursaria” groups in Paramecium.

Notes: SUMMARY. Strains E, S and W of Tetrahymena pyriformis were examined for their ability to carry out the reactions of the Krebs-Henseleit urea cycle, using growth and enzyme studies. None of the strains was able to grow on either citruliine or ornithine in place of arginine, and proline was as active as citrulline or ornithine in sparing arginine. So little citrulline or arginine was synthesized by cell-free preparations as to be of no significance in the growth or nitrogen metabolism of the ciliates. Slight arginase activity could be detected in homogenates, but no urea was found in cultures. No urease activity could be detected using urea-C14.

Notes: SUMMARY. An eimerian coccidian is described from the flying squirrel, Glaucomys volans, in Florida. It is identified as the same eimerian described by Roudabush from the flying squirrel in Iowa as Eimeria sciurorum. Evidence is presented that Roudabush incorrectly identified the organism. It is renamed as E. parasciurorum nov. sp. Mature oocysts have mean measurements of 29 × 16°, an index of 1.82, are cylindrical with rounded ends, have a dual membrane, and no extra residual body. Oocysts are without micropyle. Four egg-shaped, mature sporocysts in the oocyst have mean measurements of 11.2 × 6.2°, an index of 1.81, contain an oval, granular, intraresidual body and two pyriform sporozoites 10 × 3.2°, index 3.11.

Notes: SUMMARY. Two centrioles, an old one and a new one, are always present in the resting cell. From prophase onward two new ones and two old ones are present. Beginning with the resting stage, five types of centriole life cycles are described and compared with one another: In type 1, both centrioles are elongate; in type 2, the old one is long and the new one, which is short, elongates in prophase; in type 3, both are short, both elongate in prophase, and both, except for their anterior tips, degenerate in late telophase; in type 4, both are long but in prophase their distal ends become free of the rest of the centrioles, these ends migrate to center or posterior end of cell, where, after they produce the achromatic figure and it completes its function in nuclear division, they degenerate; in type 5, both are short and neither elongates at any stage of its life cycle.New centrioles are produced by the anterior ends of old ones. In their first generation, centrioles produce only extranuclear organelles (flagella, parabasals, axostyles, etc.); in their second and later generations, they produce only the achromatic figure (gametogenesis in Trichonympha and reorganization in Barbulanympha and Rhynchonympha are exceptions to this rule).The distal ends of centrioles in some types of cycles are surrounded by centrosomes; in others they are not. In one type of centriole life cycle a small central spindle is present in the resting cell in two genera; in the other types this is not the case.

Notes: SUMMARY. The endogenous development of the life cycle of Eimeria alabamensis Christensen, 1941, occurs in the nucleus of the intestinal cells of cattle. Calves were killed at various intervals after inoculation with infective oöcysts to study the endogenous cycle. Excysted sporozoites were found in the contents or scrapings from the walls of rumen, omasum, small intestine, cecum, and colon. They were found in the cytoplasm of intestinal epithelium at 2 days. Schizonts were found in the nuclei beginning at 2 days, but the number was low by the 8th day. Merozoite numbers usually ranged between 16 and 32. Some host nuclei contained as many as 48 or more, but these appeared to be the result of more than one schizont merging in the same host nucleus. Merozoites were slender, spindle-shaped bodies while still in the schizont walls, but were short with bluntly rounded tips when found in intracellular spaces and crypts. Gametocytes were found as early as the 4th day. Most of the stages of gametogenesis were limited to the lowest third of the small intestine, but in heavy infections some were also found in the cecum and upper colon. Microgametocytes were multinucleate and were more densely stained than the uninucleate macrogametocytes. The ratio of macrogametocytes to microgametocytes in 100 gametes was 78: 22. Oöcysis with “shells” were found in sections of the lower 20 feet of the ileum on the 6th day, which coincided with the shortest prepatent period reported previously. As many as three schizonts or microgametocytes or four or five macrogametocytes or oöcysts could be found in the same host nucleus. The variations in shape of the oöcysts appeared to be dependent on the number of oöcysts crowded into each nucleus.

Notes: SUMMARY. The role of centrioles in achromatic figure production is considered when the number present varies from 1–8. Each centriole after it becomes elongate produces astral rays from its distal end. Some of these rays remain free; some, by joining centromeres, become chromosomal fibers; and some, by joining and growing along those produced by one or more other centrioles, produce the central spindle portion of the achromatic figures. Thus, one centriole may function cooperatively with one to several others in the production of central spindles. But at least two centrioles must be present, and in the proper spacial relation to each other, to form a central spindle; one by itself can form only free astral rays, no central spindle or chromosomal fibers.The flagellated areas (to which the centrioles are anchored anteriorly) play an important role in determining the position of the distal ends of the centrioles with respect to one another, and the position of these ends, in turn, in a large measure, determines the types of achromatic figures produced, particularly the number of central spindles.

Notes: SUMMARY. Observations on binary fission of Lacrymaria olor show that it is a transverse fission. It involves probable intranuclear division of the micronucleus. Both micro- and macronucleus elongate in preliminary stages. Each is ultimately divided as cytoplasmic constriction cuts the spindle fibers of the former, and the connecting, nucleoplasmic thread of the latter.Surging movements of cytoplasm after fission elongate the daughter organisms and move new nuclei to normal, central sites. The anterior proboscis of the posterior daughter regenerates suddenly, complete with coronal cilia. Metachronal waves along ciliary meridians, strongly reversed on the posterior daughter, cause an oscillating movement which pulls the two apart, except for a slender, pellicular thread, ultimately severed. Until broken, this thread connects the rear tip of the anterior animal to the forward end of the proboscis of the posterior one. The organism is semi-quiescent, with proboscis retracted (except spasmodically) throughout fission. After fission the anterior animal quickly begins feeding movements and soon swims away. The posterior animal requires about half an hour before being able to begin feeding and swimming movements.The anterior contractile vacuole of the original animal becomes the primarily active vacuole of the anterior daughter; the posterior one that of the posterior daughter. Missing vacuoles are regenerated by the daughters in about one hour after fission. The division process requires about one hour for completion at 22.4°C.

Notes: SUMMARY. The multiplication rate of Tetrahymena pyriformis HS in proteose peptone medium was measured at 12 temperatures between 18.4°C. and 36.6°C. At the temperature optimum, 32.5°C., the generation time is 2.25 hours. The upper lethal temperature lies between 36.6°C. and 38.0°C. Similarly, a study of Tetrahymena pyriformis GL revealed a temperature optimum for multiplication of 29°C. with a generation time of 3.70 hours. The upper lethal temperature falls between 34.6°C. and 35.4°C. At all temperatures employed the HS strain of organisms multiplies more rapidly than strain GL. Under identical conditions, the two strains have distinctly different growth optima, upper lethal temperatures and growth rates.As measured by multiplication rate the readjustment to a sudden change in temperature (from 18.4°C. to 27.7°C.) is completed very rapidly, with an effective lag time of about 1 hour. Such a shift in temperature gives rise to a small degree of division synchrony during the first and second population doublings which follow. Subsequently, all traces of division synchrony are lost.

Notes: SUMMARY. Test tube cultures of Tetrahymena pyriformis GL in the early maximum stationary phase of growth were used as inocula. After the elapse of a short lag phase a rapid transition to the logarithmic phase of growth was observed in cultures grown on peptone media(4,6). During the early phase of exponential multiplication more cells (as expressed on a percentual basis of the population number) were in the visible stage of cytoplasmic fission than after the elapse of 5 to 6 generations. Analysis of comprehensive data suggests that the higher division index in the early logarithmic phase of growth is not the expression of a synchronization of cells in metabolic respects but rather indicates a prolongation of the stage of cell fission during this phase.

Notes: SUMMARY. Ochromonas malhamensis (Pringsheim strain) can be grown above 35.5°C.; below 35°, the previous chemically defined medium supports dense growth. The B12 and thiamine requirements rise steeply with temperature, and growth promotion by folic acid emerges; folic acid spares the enhanced B12 requirement. B12 is spared also, perhaps wholly bypassed, by purines + pyrimidines + amino acids (below 35°, exogenous purines, pyrimidines, and folic acid have little effect). Requirements also emerge for glycine (spared by serine), valine and isoleucine (their ratio is critical; leucine and threonine assist in maintaining a good balance), and, at very slightly higher temperatures, phenylalanine, tryptophan, cystine, and lysine. Requirements for Mg, Fe, Zn, and Mn appear to rise steeply with temperature; metal toxicities have to be circumvented carefully. The proportion of histidine + arginine to carbohydrate has to be increased, and a Krebs-cycle component such as succinic acid becomes stimulatory. At 36.3–36.7°, a further supplement of crude natural materials such as an autoclaved suspension of Ochromonas cells is needed. Relevance of these findings to fever stress in vertebrates, general mitochondrial function, and repair of radiation damage, is discussed.

Notes: SUMMARY. According to Kahl the trichostome genus Trichopelma may be considered to include five species: T. sphagnetanim, T. eurystoma, T. euglenivora, T. opaca, and T. torpens. A sixth species is added in the present account. The following constant characteristics distinguish it from the five earlier described ones: total lack of trichocysts; differences in the morphology of the body surfaces; dissimilarity of the upper and lower surfaces in shape (one plane, the other convex), in ciliation, and in number of cuticular furrows; unique location of the contractile vacuole.

Notes: SUMMARY. Isospora citelli n. sp. is described from the rock squirrel, Citellus variegatus Utah, from Grand Canyon National Park, Arizona. Its oocysts are subspherical, 22.4 by 21.5 μ, with a smooth, two-layered wall, an oocyst refractile globule and a sporocyst residuum, but without a micropyle or oocyst residuum.

Notes: SUMMARY. Leptomonads of Leishmania tarentolae were grown continuously in a defined medium containing: inorganic salts', glucose, hemin, 17 amino acids, purines and pyrimidines, and a mixture of vitamins of the B group. In this medium the population of organisms reached about 20 to 50 million per ml. alter 1 week at 27°C. Only slightly better growth occurred in a partially defined medium containing bovine plasma fraction V. In earlier experiments, however, omission of the plasma fraction resulted in decreased growth, and under these circumstances cholesterol or lecithin had growth-stimulating effects. In later experiments in the fully-defined medium no effect of these lipids could be found. The leptomonads were shown to require at least the following substances: inorganic salts; a source of purines and pyrimidines; tryptophan and the nine other amino acids essential for the growth of rats, glutamic acid, tyrosine, proline, serine, one or more of the group alanine, glycine and aspartic acid; folic acid, biotin, pantothenic acid, nicotinamide, riboflavm, thiamine, and either pyridoxine plus choline or pyridoxal or pyridoxamine. Choline at 2 × 10−5 m gave optimal growth in the presence of pyridoxine at 1 × 10−5 m. In a medium with a suboptimal concentration of choline (0.4 × 10−5 m) the leptomonads grew through nine transfers but they were mostly somewhat rounded and aflagellate.

Notes: SUMMARY. Trichopus lachmanni n. sp. possesses, in common with other members of the family Dysteriidae, a fixation organelle composed of vesicles and a secretory ampoule. But no “foot-like” appendix exists in this species, and the ampoule opens at the bottom of an antapical pit which bears a short fringe of membranelles derived from the somatic ciliature. The vibratile fringe participates in the spinning of the glutinous secretion which temporarily fastens the organism to the substrate. This specialized ciliature is characteristic of the genus Trichopus which was created by Claparède & Lachmann for a species, T. dysteria, which, though insufficiently described, is certainly different from T. lachmanni.

Notes: SUMMARY. Various species of ciliates are characterized by the formation and accumulation in the cytoplasm of mineral concretions which are refringent, isotropic or anisotropic. These cytoplasmic inclusions most often are composed of calcium carbonate; in several species, however, their nature remains partially or even totally undetermined. The isotropic calcium-containing concretions often exhibit a definite shape; the calcium carbonate in this case appears to be bound to an organic substrate. The physiological role of the calcic concretions is not known; their characteristic presence in a given species is not necessarily related to ecological conditions. In a few species the calcification is localized in definite structures: spicules, skeletal plates, or otoliths of organelles supposedly sensory in nature.

Notes: SUMMARY. The combination Tween 80 and cholesterol replaced blood serum as a requirement for the cultivation of Tritrichomonas foetus. Choline + potassium glycerophosphate enhanced growth in the presence of Tween 80 + cholesterol. A method for ensuring adequate cholesterol suspension-an essential factor for consistent growth-is described.

Notes: SUMMARY. High variability within cultures of Tritrichomonas batrachorum (from Bufo boreas halophilus, Rana catesbeiana, and Rana pipiens) casts doubt on the validity of length measurements for species designation.The morphology differs from that described previously. The axostylar capitulum is a complex structure with a preblepharoplastic portion and a perinuclear cup spreading laterally in curved membranes ending in filaments. The parabasal apparatus is Y-shaped with a very short base.Two types of amoeboid activity occur. Filopodia are used for anchorage. Their bases migrate and the filopodia may fuse and reseparate as in foraminifers. Ingestion is an amoeboid process utilizing lobopodia. Food adherent to a lobopod is invested in a food cup at the surface. Ingrowth of the lip of the food cup forms the food vacuole, or in cases of cannibalism, constricts the prey and forms a food tube pushing a vacuole before it. Repeated, this produces an alternating series of vacuoles and tubes. There is a pseudo-amoeboid degenerative process in which the flagella, withdrawn into the cytosome, continue to move and produce non-functional lobopod-like protrusions.An actual cytostome has not been observed, but there is a region of reduced staining intensity ventral to the axostylar capitulum.

Notes: SUMMARY. A study has been made of the cytology of an undescribed species of Spirostomum. The species is much smaller than S. ambiguum. The peristome extends to about half the length of the animal, whereas in S. ambiguum it is about two-thirds the body length. The nuclear apparatus reveals some striking differences. The macronucleus is cylindrical, and not chain-like, in the vegetative animal. The micronuclei are far fewer than in S. ambiguum and number 6–15, but are larger in size. During binary fission, the macronucleus becomes condensed into an oval or polymorphic mass and is drawn out again into a cylinder before it is cut into two lengths. The micro-nuclei divide by mitosis and, whatever their number in the vegetative animal, only 7–8 take part in the division. The others presumably degenerate.

Notes: SUMMARY. The structure and life history of a new species of eugregarine, Gregarina garnhami n.sp., is described from the intestinal caeca and mid-gut of Schistocerca gregaria Forsk. The parasite destroys considerable areas of the caecal epithelium and in cases of heavy infection, the masses of parasites present in the mid-gut result in the formation of localized barriers between the gut wall and the food material in the lumen. The cephalont and sporont stages of gregarines from Locusta migratoria migratorioides R. & F. and Anacrydium aegyptium Linn. are shown to be similar to those from Schistocerca gregaria and are believed to belong to the same species.

Notes: SUMMARY. Oxygen concentrations of 70–80 per cent of an atmosphere destroy all chromosomes of the flagellate Trichonympha provided the oxygen treatment is carried out during the early stages of gametogenesis at which time the chromosomes are in the process of duplicating themselves. This treatment does no damage to the cytoplasm and its organelles. Following the loss of chromosomes, the centrioles function in the production of the achromatic figure, the flagella, and‘parabasal bodies. Then the cytoplasm divides, thus producing two anucleate gametes which make some progress in the cytoplasmic differentiations characteristic of normal male and female gametes of Trichonympha.It is also possible, with somewhat higher concentrations of oxygen, with temperatures slightly above the freezing point and a longer period of treatment, to destroy the chromosomes of resting asexual nuclei in several genera of the flagellates that live in the roach Cryptocercus. So far as one can determine by observing organisms so treated, their cytoplasm and organelles are not injured.

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: SUMMARY. Known chemical compounds have replaced the three supplementary factors previously necessary for the growth of Euplotes patella feeding on Chilomonas paramecium under bacteria-free conditions. The factor found in an extract of liver was identified as thiamine. The factor supplied by extracts of certain bacteria has been tentatively identified as folinic acid. A combination of 8-azaguanine and the riboflavin analog, flavotin, has been substituted for the factor found in yeast extracts. Inorganic salts and sodium acetate have been incorporated in the supplementary medium to promote the growth of the flagellate food organisms. Euplotes has also been cultured on Tetrahymena pyriformis in a medium containing 8-azaguanine and flavotin. The requirement for supplementary growth factors in this carnivorous ciliate has been interpreted as definitely involving intermediates in purine metabolism.

Notes: SUMMARY. An improved assay of vitamin B12 is described. The z strain of Euglena gracilis, which grows more vigorously than the bacillaris strain previously used, is recommended. The pattern of B12 specificity of the two strains appears to be the same. A new medium containing sucrose, aspartic acid, glutamic acid, and glycine at pH 3.6 is well buffered and allows luxuriant growth. Vigorous utilization of sugar appears to depend on readily available nitrogen and a Krebs-cycle component; these requirements are well met by aspartic acid (or asparagine) and glutamic acid. The proposed procedure is especially suitable for the measurement of B12 in blood serum because rise in pH and precipitation of serum proteins during incubation are minimized. Like bacillaris, the z strain allows the distinction between “combined” and “uncombined” B12 in serum. Serum may be an appropriate test material to tell whether such phagotrophs as Peranema can better utilize bound forms of vitamins than can the related osmotrophs. Patterns of B12 requirements and occurrence are discussed as phylogenetic markers.

Notes: SUMMARY. Cells from a clonal culture of Tetrahymena pyriformis W were cultured in the presence of 10-4 M KCN for a prolonged time until they became “adapted” to cyanide. The effect of 10-3 M KCN upon respiration in the “adapted” cells was compared with the effect upon “normal” cells of the same clone grown in the absence of cyanide. The direct method of Warburg was employed.Adapted cells are more resistant against respiratory inhibition than are normal cells. Resistance is due both to a factor or factors retained within the cell and the extracellular factor(s) released into the medium by the adapted cells during their growth. The intracellular factor is acid labile, and apparently may be developed within a short time. The extracellular factor is heat labile and may cause normal cells to be more resistant against respiratory inhibition by KCN.Resistance to respiratory inhibition is lost if adapted cells are cultured in the absence of KCN. It is proposed that changes involved in gain or loss of cyanide resistance are due to physiological adaptation and not to the usual genetic influences.

Notes: SUMMARY. A neopeptone blood broth was a satisfactory medium for cultivation of the frog trypanosome T. ranarum, though it did not support as consistently good growth as the corresponding diphasic medium. The superiority of diphasic over liquid medium could be explained only by the presence of a reserve of nutrients in the agar slant which diffuse into the liquid phase. Inocula from culture tubes 12 days or less in age resulting from a succession of rapid transfers appeared to be necessary for maximal growth.

Notes: SUMMARY. Great numbers of a new ameba have been collected from freshwater, lagooning, disposal tanks for citrus pulp wastes. The ameba is morphologically similar to the marine Flamella magnifica (Schaeffer, 1926), and clearly belongs to the genus. It differs sufficiently in the formation and characters of locomotor organelles, and in habitat, to be considered a separate species, Flamella citrensis n. sp.

Notes: SUMMARY. The enzymatic induction of fatty acid oxidase activity in Polytoma can be characterized as follows: (1) the preferential synthesis of oxidase activity can be induced in non-proliferating cells, (2) the rate of induction is dependent upon the concentration of exogenous nitrogen, (3) the rate of induction is also dependent upon the age of the cells, (4) with log-phase cells, the rate of synthesis is highest and the kinetics of synthesis, linear; the rate of synthesis by older cells is low and variable in form, (5) ultraviolet irradiation selectively inhibits induction at doses which do not inhibit respiratory activity, oxidative assimilation or nitrogen utilization.

Notes: SUMMARY. The trichomonad occurring in the nasal cavity of the domestic pig, Sus scrofa, is described and figured. With Heidenhain's iron-hematoxylin and protargol (protein-silver) stains, the specific characters are as follows: Pyriform in shape; length 8.8–18.4 μ (average 13.6 μ); width 3.2–8.0 μ (average 4.8 μ); blepharoplast of several granules; three anterior flagella with the longest 10.4–16.8 μ in length ending in knob-like enlargements; full length undulating membrane with four to six subequal folds and containing marginal and accessory filaments; trailing flagellum 4.8–11.2 μ in length; full length costa with fine subcostal granules; hyaline rod-shaped axostyle with bulbous capitulum, chromatic ring and conical tip; tube-like parabasal body 3.2–4.8 μ in length; oval-shaped nucleus 3.7–5.0 μ in length and 2.2–3.0 μ in width; cytostome; and vacuolated cytoplasm containing food vacuoles.Taxonomy of trichomonads in the respiratory and digestive systems of swine is discussed and the nasal trichomonad is compared with the two different forms of Trichomonas found in the cecum. The conclusion is that the nasal form is of a different species from the trichomonads of the cecum. The close similarity between the nasal form and Tritrichomonas foetus is emphasized. The writer suggests that the nasal form should not be given recognition as a new species until its true relationship with T. foetus is revealed.

Notes: SUMMARY. Saprophilus muscorum Kahl, 1931 is an edaphic species which has been identified in cultures of soil and forest litter. This ciliate has the buccal ciliary apparatus of the family Tetrahymenidae Corliss. There is only one post-oral meridian and 15 bipolar meridians, 8 of which meet ventrally at the pre-oral suture. The cilia are long and sparse and there is a prominent longer caudal cilium. Trichocysts are present. Resting or resistant cysts are formed readily.

Notes: SUMMARY. To determine whether Tetrahymena pyriformis could infect Deroceras reticulatum and become morphologically modified in the same way as the parasitic phase of T. limacis, 50 slugs were exposed for 10 days to an amicronucleate clone of T. Pyriformis and 50 were exposed for the same period of time to a micronucleate clone. The slugs were then transferred to clean containers for another 10 days, to allow ciliates which had entered the slugs either to persist and multiply or, in the case of transitory infections, to disappear. An additional 50 slugs were kept in a control group for 20 days. All of the slugs had been collected at a single locality in which natural infections by T. limacis had not been noted, and were maintained in separate one-half pint milk bottles throughout the experimental period.Of the slugs exposed to the amicronucleate clone, 40 survived to the end of the experimental period, and 15 were infected. Of those exposed to the micronucleate clone, 42 survived, and 5 were infected. Forty-three of the slugs in the control group survived, and none were infected by ciliates. In some of the slugs infected by T. pyriformis, hundreds of ciliates were noted. The infections were apparently limited to the digestive gland, intestinal tract, and fluid around the viscera. Ciliates recovered from slugs were in general smaller than those growing in thriving cultures, but morphologically were typical T. pyriformis. None were observed to have a proportionately smaller cytostome or apiculate anterior end characteristic of the parasitic phase of T. limacis.

Notes: SUMMARY. The aggregative process of Dictyostelium discoideum is unaffected by most chemical and physical alterations of the environment. Such substances as vitamins, amino acids, catabolic intermediates, purines and pyrimidines, redox poising agents, enzyme inhibitors, and inorganic salts were added to the aggregative substrate. Of these, only a few exerted any influence on aggregation except at lethal concentrations. Histidine allowed the wild-type myxamoebae to aggregate at lower population densities and accelerated the aggregative process as compared with controls on minimal agar. Brief exposure to histidine irreversibly conditioned the cells. No degradation of the imidazol skeleton was detected. A rise and fall of internal soluble histidine were demonstrable. The purine base, adenine, raised the population density required for maximal center formation.

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: SUMMARY. In water taken March 3, 1956, from a tributary of the Amazon River, near Leticia, Colombia, an abundant ciliate fauna included large numbers of a species of Euplotes. Cursory examination showed a pronounced left wing like that of E. novemcarinatus Wang. Careful study, however, revealed a distribution of peristomal membranelles and peristomal morphology more like that of E. euryostomus Wrzesniowski. The positions of ventral cirri resemble those of E. woodruffi Gaw. The two right caudal cirri are furcated, as are those of the first two above-mentioned species; but the five anal cirri are not. The C-shaped macronucleus, like that of E. aediculatus Pierson, has the upper left part of the “C” somewhat depressed. A large organism, it averages 155 μ long by 130 μ broad, length ranging from 87 μ to 203 μ, and width from 67 μ to 194 μ. It is presented as Euplotes leticiensis n. sp.

Notes: SUMMARY. Following a brief historical review and critique of the main theories of amoeboid movement, the recent work of Goldacre and Lorch, relating plasmagel contraction to the folding and unfolding of protein molecules, is discussed; and some new observations are presented concerning the behavior of the plasmagel in amoebae vitally stained with neutral red. Similarities between contraction of vertebrate muscle and amoeba plasmagel are discussed, and a summary of recent work suggesting that adenosine triphosphate and actomyosin-like proteins may be involved in amoeboid movement is given. A re-examination of the meaning of the terms plasmagel and plasmasol indicates their relative nature denoting only comparative degrees of viscosity. Recent observations as to the nature of the plasmalemma are reviewed, and evidence is presented for the existence of an external slime layer in Amoeba proteus (not in all amoebae), which slides over the visible pellicle carrying adherent foreign particles forward from the precaudal region. The inadequacy of the contracting gel tube theory for explaining many types of protoplasmic streaming is pointed out.

Notes: SUMMARY. Tillina magna is a large holotrichous ciliate, of the family Colpodidae, which normally forms resting cysts. These cysts, when formed in their natural environment, withstand drying. Active animals have been excysted from dirt collected more than 10 years ago. However, until recently, laboratory work on these, as well as on most other ciliate cysts, has been done on wet cysts. A method is described for producing viable dry cysts under laboratory conditions. It consists essentially of inducing the tillinas to encyst on prepared sections of grass stems. In this way dry cysts have been formed which are viable up to 4 months. These cysts, when first formed, can be activated simply by the addition of water. Cysts which are no longer responsive to water alone may sometimes be induced to excyst by the addition of lettuce infusion. Cysts withstand extremes of temperature from -5°C. to 45°C. These facts have some bearing on the question of the factor or factors causing excystment.

Notes: SUMMARY. A study has been made of the number and morphology of the chromosomes of five species of malarial parasites as seen in living material with phase contrast microscopy. Plasmodium knowlesi, of monkeys, is essentially similar to other primate malarial parasites previously studied, having two chromosomes of unequal length. P. lophurae, from ducks, P. relictum from pigeons and sparrows, and P. floridense from a lizard all have two small chromosomes of equal size. These facts, with ether data, indicate that the genus may consist of two species complexes. P. berghei, studied in white mice and rats, has a karyotype similar to the avian and saurian malarial parasites. The suggestion is made that P. berghei, on a basis of chromosome pattern and other characteristics, is probably more closely related to the avian and saurian species of Plasmodium than to other mammalian species.

Notes: SUMMARY. The adaptation to fatty acids by Polytoma depends upon two mechanisms: 1. The induced synthesis of fatty acid oxidase which precedes growth. 2. A long-term physiological adaptation spanning several cell generations which results in an increase of the initial rate of growth.Analysis of the long-term adaptation shows that the adaptation does not result from the selection of fast-growing mutants. The generation time on butyrate of unadapted cells is initially ca. 24 hours and it is reduced to ca. 10 hours after the second subculture in butyrate medium. Adaptation to butyrate results in a simultaneous adaptation to caproate.

Notes: SUMMARY. A survey of protozoa in four water samples from Colombia, South America, yielded 84 species identifiable to genus or to species. Three of the collections were from the Amazon River and a tributary in the vicinity of Leticia, at the southern tip of the country. The fourth was taken near the high Andean town of Medellin in central Colombia.All four subphyla are represented. Forty ciliophorans, 26 mastigophorans, 17-sarcodinians, and one sporozoan are included. Of the ciliophorans all but one are euciliates in three orders. The exception is a suctorean. Two classes, and six orders of mastigophorans are represented; one class, and two orders of sarcodinians; and one class, one subclass, and one order of sporozoans. Eleven suborders, 33 families, and 49 genera are exemplified.Other protozoa seen, but not identified to generic or specific accuracy, are omitted.

Notes: SUMMARY. The division cycle was followed in four strains of Blepharisma undulans. Animals were fixed and stained at regular intervals from the end of one division through completion of the next.A comparative study of the present findings and those in the literature shows that in all strains in which the macronucleus is nodulated there is a similarity in the events that occur during division. These include a loss of some of the chromatin material, a fusion of macronuclear nodes into two masses, and a subsequent fusion of these two masses into one large, centrally located mass. This, in turn, elongates and divides into two daughter nuclei which either are nodulated at the time of separation or become so shortly after the division into daughter nuclei.Great variation exists, among different strains, in the number of macronuclear nodes present. This fact, coupled with knowledge of nuclear morphogenesis during the division cycle, renders macronuclear form of little taxonomic value at infrageneric levels.

Notes: SUMMARY. A rich source of supply of Pelomyxa palustris has recently been found. The findings and views of previous investigators on the geographical and seasonal distribution, longevity in the laboratory and reproduction of this organism are reviewed and discussed. Clone and mass cultures were successfully obtained in Carrel flasks with Spirogyra as food. Feeding is an extremely slow process so that this Pelomyxa is incapable of capturing and ingesting actively motile organisms under ordinary circumstances. Multiplication is solely by simple or multiple plasmotomy.

Notes: SUMMARY. Some of the unusual types of sexual behavior in Trichonympha are considered: cytoplasmic incompatibility of gametes as shown in the fertilization process, pronuclear incompatibility, independence of pronuclear and cytoplasmic incompatibilities, loss of extranuclear organelles of male gamete, the formation of gametes with no chromosomes, those with the diploid number, and those with numbers between these extremes.

Notes: SUMMARY. The various sexual processes in each of ten genera of protozoa of Cryptocercus have been correlated with the molting period of their host in days beginning with 50 days before ecdysis and ending 3 days after ecdysis. Some genera begin the gametogenesis portion of their sexual cycle much earlier in the molting period than others. Gametogenesis in some genera is haploid, in others it is diploid; in some it is a short process, requiring only a few hours for completion; in others it requires several days for completion. Not counting Leptospironympka and Macrospironympha, meiosis occurs after ecdysis in 6 genera and before in two. The fertilization process in some genera is too involved to make possible a simple summary. The time when gametogenesis, fertilization, and meiosis occur in the molting period of the host seems to be determined by the nature of the various genera of protozoan parasites themselves rather than by their host, although the host, in each case, is always responsible for the initiation of the sexual process as well as for carrying it to completion.

Notes: SUMMARY. A small soil amoeba was purified by an agar-surface migration method. The amoeba was grown axenicly in a liquid medium composed of 1% proteose peptone, 1% glucose, and inorganic salts. The amoeba was identified as a species of Acanthamoeba. A hypothesis on the mechanism of agar-surface purification of amoebæ is proposed. The nutritional requirements of this isolate are discussed; it is concluded that this organism metabolizes glucose.

Notes: SUMMARY. An electron microscope study of thin sections of duck erythrocytes infected with Plasmodium lophurae revealed that the so-called “residual body” is a food vacuole formed by invagination from the cytoplasm of the host cell. Several such food vacuoles may exist in a single parasite. Digestion of hemoglobin evidently proceeds only within these food vacuoles, since they are the only place in the parasite where the characteristic malarial pigment granules may be found. This finding changes the role ascribed to the residual body and gives a new concept of the feeding mechanisms in P. lophurae and other malaria parasites. The cytoplasm of the host is taken in by the parasite by phagotrophy and not only as previously assumed, by diffusion.The fine structure of P. lophurae shows all major components found in other protozoan and metazoan cells. Some of the organelles appear to have a much simpler structure connected probably with the highly specialized intracellular parasitic life.

Notes: SUMMARY. Transfers of Euglena gracilis to fresh media gave rise to increased volumes of the flagellates, the magnitude of expansion varying with temperature, pH, osmotic pressure, and number of nutritional particles in the medium. Expansion was accompanied by decreased protoplasmic density and increased intracellular solids and water. When the population density of the flagellates was more than optimal, competition for substrates was reflected in reduced maximum volume. Below the optimal range, a similar decrease in maximum volume was observed.

Notes: SUMMARY. A ciliate found in the renal organ of the gray garden slug, Deroceras reticulatum, is referred to Tetrahymena (Paraglaucoma) rostrata (Kahl). In the parasitic phase, the ciliate is evidently not histiophagic. It is readily cultivated in bacterized tissue infusions, and has been established in axenic culture in yeast extract.The number of complete primary ciliary meridians in ciliates of the parasitic phase has been observed to range from 41 to 58; in ciliates from cultures, the number of meridians has been observed to range from 28 to 37. In culture, the form of T. rostrata from D. reticulatum appears to be morphologically identical with a strain (NZ-4) recovered from soil in New Zealand.

Notes: SUMMARY. In a survey of 52 rodents of 25 species from Grand Canyon National Park, Arizona and its vicinity, the following species of Eimeria are described: E. tamiasciuri n. sp. from the red or spruce squirrel, Tamiasciurus hudsonicus; E. lateralis n. sp. and Eimeria sp. from the mantled ground squirrel, Citellus lateralis; E. eutamiae n. sp. from the cliff chipmunk, Eutamias dorsalis; E. thomomysis n. sp. from the pocket gopher, Thomomys bottae; E. perognathi n. sp. from the rock pocket mouse, Perognathus intermedius; E. albigulae n. sp. from the white-throated woodrat, Neotoma albigula; E. operculata n. sp. from Stephens' woodrat, Neotoma stephensi; E. peromysci n. sp. and E. arizonensis n. sp. from the piñon mouse, Peromyscus truei; E. eremici n. sp. from the cactus mouse, Peromyscus eremicus; and E. onychomysis n. sp. from the northern grasshopper mouse, Onychomys leucogaster.

Notes: SUMMARY. The central canal of the suctorial tentacle of Ephelota is limited by a fine pellicle composed of numerous longitudinal fibrils and bearing 16–18 membrano-fibrillar ridges arranged radially in the lumen of the canal. This structure resembles that of the myonemes in the heterotrichous ciliate Stentor.The prehensile tentacle of Ephelota contains 4–6 axial protein fibers each consisting of a lamello-fibrillar bundle and isolated from one another by thin intracytoplasmic membranes.In both types of tentacle the cytoplasmic portion is immediately limited by a very thin pellicle which is continuous with the “epiplasmic membrane” and covered by the alveolar cuticle which envelops the entire body of the ciliate.

Notes: SUMMARY. A medium is described for the axenic culture of Paramecium multimicronucleatum which is chemically defined except for one constituent—a nondialyzable fraction (NDF) of an exhaustively dialyzed yeast extract. Using this medium it has been possible to demonstrate an absolute requirement for stigmasterol and the following B-vitamins: folic acid, riboflavin, thiamine and pantothenic acid. There was evidence that nicotinamide and pyridoxal are also required for continued growth of the organisms. The nitrogen requirements could be met with any of the following: proteose peptone, purified casein, crystalline ovalbumin, or a mixture of amino acids. A carbon source, in addition to that supplied by the NDF or the amino acids, was essential. Sodium acetate and sodium pyruvate would satisfy this requirement.

Notes: SUMMARY. Pleurotricha lanceolata was cultured in an aqueous extract of Cerophyl with Tetrahymena sp. as the primary food organism. It was induced to form resting cysts by crowding in the absence of food in a modified Osterhout solution. Cysts formed in this medium remained viable for several months.The morphology of the cysts and of animals undergoing excystment was studied both in the living state and in stained preparations. The excystment process was recorded by camera lucida drawings. These studies revealed no endomictic nuclear reorganization, and no extrusion of nuclear material as had been previously reported.An analysis of certain chemical and physical factors which affect excystment showed the following: the rate of excystment is temperature controlled; increasing the pH of the excystment medium increases the time required for excystment; in low concentrations some aqueous plant extracts are effective excysting agents; dilute solutions of certain plant acid mixtures neutralized with KOH are likewise effective; a number of organic substances, e.g., Bacto-yeast extract and Bacto-peptone, are also effective; and the presence of bacteria retards the rate of excystment.

Notes: SUMMARY. Measurements of the length and width of a total of 6,915 unsporulated oocysts of Eimeria necatrix from 11 infected chickens revealed a length range of 12.1-28.9 μ, width range of 10.8-23.8 μ, and a shape-index (length/width) range of 1.0-1.64. The average size range of the samples of 25-100 oocysts (mean, 66 oocysts) constituting this total and taken on the various days of the patent periods was 15.6–23.9 μ× 13.9–19.5 μ. The lengths, widths and shape indexes of the oocysts constituting such samples usually described unimodal, near-normal frequency distribution curves.The average size of oocysts issuing from an average chicken on an average day of the patent period of the infection was, with standard deviations, 19.7 ± 1.82 μ× 16.7 ± 1.20 μ. The average standard errors for the length and width were 0.237 μ and 0.158 μ, respectively, in samples of the size indicated. A tendency to increase slightly, though significantly, in size after the first three days of the patent period was noted; also, a slight, though significant, linear increase from the first to the seventh day, inclusive. A slight, though significant, tendency to shorten with the passing of the days of the patent period was detected.Analysis of variance revealed much variation in oocyst size from bird to bird on a given day and for given bird and day combinations, but significant day to day variation was demonstrated for width only. By splitting the variance during the first seven days of the patent period into its parts, it was determined that the mean oocyst size during this period was, with standard errors, 19.59 ± 0.238 μ× 16.63 ± 0.200 μ. Further analysis disclosed that a considerable reduction in oocysts measured could be accomplished, with no loss of accuracy, if fewer measurements were taken per bird and more birds were employed.

Notes: SUMMARY. Spirobutschliella clignyi, which occurs in the intestine of Pomatoceros triqueter, was found in numbers ranging from 1 to 98 in about 45% of the host specimens examined at Drøbak. Comparative incidence of infection in closely neighboring host specimens suggests that migration of normal sized ciliates is not the main route of infection. The distribution of dwarf ciliates indicates the possibility of their being involved in transmission. The general morphology and the absence of skeletal structures would seem to permit inclusion of the species in the family Anoplophryidae.

Notes: SUMMARY. Three enzymes of the glycolytic pathway, hitherto not identified in Trichomonas vaginalis, have been studied: phosphoglucomutasse, α-glycerophosphate dehydrogenase, and lactic dehydrogenase.The identification of seven phosphorylated glycolytic intermediates is reported.The operation of glycolysis in T. vaginalis is postulated from enzymatic as well as chemical studies.

Notes: SUMMARY. Sodium pyruvate, glutathione, potassium cyanide, dextrose, sucrose, 3 nucleic acid derivatives, 11 B-vitamins, and 22 amino acids were tested for their ability to protect Astasia longa against the lethal damage induced by ultraviolet radiation. Compounds which protected when added to a cell suspension just before irradiation were cystine, phenylalanine, tryptophan, tyrosine, adenine, cytidylic acid, uracil, and sodium pyruvate. None of these compounds protected when added immediately after irradiation. Except for phenylalanine, solutions of these compounds afforded protection when used as filters between the ultraviolet source and the flagellates. Cysteine failed to protect when added just before irradiation, but gave good protection when cells were grown in its presence.

Notes: SUMMARY. The number of complete primary ciliary meridians in Tetrahymena limacis found in natural infections in the slug Deroceras reticulatum has been observed to range from 32 to 40. To study the range in the number of meridians in clones in culture, 10 ciliates were pipetted singly from each of two natural infections into sterile 1% (w/v) yeast extract to which 400 units of potassium penicillin-G and 500 micrograms of dihydrostreptomycin sulfate per ml. had been added aseptically. Ten ciliates were also pipetted from each of these natural infections into infusions of tissue of the digestive gland of D. reticulatum. Altogether, 28 clones (13 axenic clones in yeast extract and 15 bacterized clones in tissue infusions) were established.The shape of ciliates in thriving axenic cultures is generally ovoid or pyriform, and similar to that of ciliates in bacterized cultures. However, ciliates in axenic cultures are sharply apiculate at the anterior end and free from inclusions other than small lipoid granules, and in these respects resemble ciliates of the parasitic phase. The cytostome of ciliates in bacterized and axenic cultures is larger in proportion to the size of the body than it is in the parasitic phase.The ranges in the number of ciliary meridians in ciliates of the two natural infections from which the clones were established were 33 to 40 and 32 to 38, whereas the number of meridians in the clones taken as a whole ranged from 25 to 32. Fifteen of the clones showed extremes of 26 and 30.One of the clones was re-introduced into D. reticulatum by exposing 50 slugs to a culture of the ciliates for 10 days. The slugs were then transferred to clean containers for another 10 days. Forty-one of the slugs exposed to ciliates survived the experimental period, and 32 became infected by T. limacis. Forty-four of 50 slugs in an unexposed control group survived, and none were infected by ciliates. In the ciliates from slugs of the experimental series, the number of complete primary meridians ranged from 28 to 36. However, more than half of the ciliates in the experimental infections possessed incomplete rows, and some individuals had as many as five of these. Ciliates in natural infections and in cultures sometimes have incomplete rows, but rarely show more than one such row. The incomplete rows in ciliates re-introduced into slugs are considered largely to be incipient segments of future complete rows. They occur most commonly in the post-oral region, and particularly between row 1 (the so-called stomatogenous meridian) and the next complete row to the observer's right. It appears, therefore, that the post-oral region is a zone in which most new rows are proliferated.