bluuebunny/crossref_metadata_2025 huggingface dataset:
Electron Microscopy of Centrifuged Amoeba proteus*
Authors: DANIELS EDWARD W.
Published: May 2007

SYNOPSIS. The subcellar components within living inter‐phase Amoeba proteus organisms were stratified by centrifugal forces which ranged from 700 g to 10,000 g. The amoebae were fixed in OsO4 immediately afterwards, embedded in Epon resin, and examined with an RCA EMU‐3E or an RCA EMU‐3F electron microscope. For convenience in presentation, the strata are classified into 8 zones and discussed in order from the centripetal (zone 1) to the centrifugal pole. Zone 1 contains the fat globules most of which range in size from 1 to 5 μ; the centrifuged globules do not coalesce, probably because each globule has a surrounding membrane. Zone 2 has the contractile vacuole, groundplasm, and some irregular vacuoles which are a few microns in size. Zone 3 is the largest in volume and contains mostly groundplasm in which are suspended numerous small vesicles (ca. 0.5 μ or less). Many of these are about 0.3 μ in size and appear to be the alpha granules previously described by light microscopists as minute particles (ca. 0.25 μ), and also studied by us with the phase microscope in living, centrifuged amoebae. In addition, this zone contains electron‐dense prolate spheroid bodies which are oriented in the direction of the centrifugal force. Zone 4, which is not sharply separated from zones 3 and 5, contains a variety of vesicles and vacuoles ranging from 0.1 μ to a few microns in diameter, and scattered electron‐dense spheroidal bodies, all suspended in groundplasm. Zone 5 contains the nucleus and a well defined stratum of Golgi bodies. Zone 6 is the mitochondrial stratum with quite distinct borders while zone 7 has the food vacuoles and the infective organisms. Zone 8 is made up of membranous vacuoles containing crystals. In amoebae centrifuged at 10,000 g the spaces between the crystal vacuoles have a high concentration of 40‐mμ electron‐dense particles that frequently appear in small aggregates. Some components, such as the small vesicles and the electron‐dense prolate spheroid bodies characteristic of zone 3, do not form a sharply defined stratum even at forces of 10,000 g. A comparative electron microscope study is made between centrifuged A. proteus and Pelomyxa illinoisensis amoebae, the latter being relatively radiosensitive.
A Morphological Study of Trichomonads and Related Flagellates from the Bovine Digestive Tract*
Authors: JENSEN EMRON A. , HAMMOND DATUS M.
Published: May 2007

SYNOPSIS. Of 45 cattle sampled, 30 and 31 were found to have trichomonads in the rumen and cecum, respectively. No trichomonads were found in the abomasum or small intestine of these cattle. Trichomonads were found in the cecum of 16 of 21 calves. Of 17 sheep sampled, trichomonads were found in the rumen of 8 and in the cecum of 7. Trichomonads were found in all of 14 cecal samples from pigs; 12 had Tritrichomonas suis, 7 had Tetratrichomonas buttreyi and 4 had Trichomitus rotunda. Media used in attempting to cultivate trichomonads included Diamond's, modified Plastridge, thioglycolate, cecal extract, rumen extract, and CPLM. Protargol, Giemsa, and iron hematoxylin techniques, as well as phase‐contrast observation of living and osmic acid‐fixed specimens, were used in the study of morphology. A pentatrichomonad was found to have the highest incidence of any flagellate in the bovine rumen and cecum; it was easily cultivated in several different media. Two strains from the rumen were found to have similar growth curves, but in 2 clones from the cecum and 2 strains of Pentatrichomonas hominis of human and canine origin, the growth curves were distinctly different. The bovine pentatrichomonad was closely similar in cultural characteristics and morphology to P. hominis and was considered to belong to this species. Another trichomonad occurring in the cecum and rumen of cattle closely resembled Tetratrichomonas buttreyi from the cecum of swine in morphology and response to cultivation; these were considered conspecific. Monocercomonas ruminantium was found in the rumen of cattle and redescribed. An organism with 4 flagella arising in pairs was found in the cecum and feces of cattle, and described as Monocercomonoides bovis n. sp. Other flagellates observed in samples from the rumen were Callimastix frontalis and Chilomastix sp.; Giardia bovis was seen in samples from the small intestine, and a species resembling Retortamonas ovis in samples from the cecum.
Nuclear Misbehavior in an Aberrant Inbred Tetrahymena*
Authors: NANNEY D. L. , NAGEL M. J.
Published: May 2007

SYNOPSIS. Breeding anomalies in an inbred strain (B1) of syngen 1, Tetrahymena pyriformis, are traced to aberrant chromosomal constitutions of the micronuclei. The origins of the micronuclear defects have not been established, but they probably arise in much the same manner as those observed earlier in “semi‐amicronucleate” clones, except that they occur later and in lower frequencies. The abnormal nuclei are impaired in their ability to carry out the maneuvers required for normal conjugation; some are blocked in MI, most after MII; the occasional cells in which nuclear reorganization is completed have visibly defective macronuclear anlagen and are inviable. When crossed to normal strains, nuclear misbehavior is induced in them and again very few if any viable exconjugants are produced. The details of the aberrations are discussed with reference to the patterns of nucleocytoplasmic interaction in conjugation.
Studies on the Macronucleus of Paramecium aurelia. II. Development of Macronuclear Anlagen
Authors: JURAND A. , BEALE G. H. , YOUNG M. R.
Published: May 2007

SYNOPSIS. The development of the macronuclear Anlagen of Paramecium aurelia was studied by means of electron, light and ultra‐violet microscopy of timed stages following conjugation. In the youngest Anlagen, no differentiated structures could be made out, and staining reactions gave little or no indications of the presence of DNA or RNA. As development proceeds, a number of conspicuous “sponge‐like” RNA‐containing bodies surrounded by a “matrix” containing DNA can be seen. Eventually these RNA bodies develop DNA centres and apparently disintegrate, yielding the “large bodies” characteristic of the mature macronucleus, and the “small bodies” then also appear. The relation of these observations to interpretations of the structural elements in the macronucleus is discussed.
Calcium45 Turnover in a Mineralizing Coccolithophorid Protozoan*†
Authors: ISENBERG HENRY D. , LAVINE LEROY S. , MOSS MELVIN L. , SHAMOS MORRIS H. , WEISSFELLNER HEINRICH
Published: May 2007

SYNOPSIS. Ca45 addition to cultures of Hymenomonas, a coccolithophorid chrysomonad, cultivated axenically, led to the autoradiographic confirmation of the intracellular nature of coccolithogenesis. Quantitative studies with isotopically enriched Ca+2 indicate the greatest activity resides in the intracellular fraction. Age of the cultures at the time of isotope addition did not appear to affect the specific activity of the coccoliths. Exchange between cell‐free isotopically enriched coccoliths and the environment was also demonstrated. The findings are discussed especially from the viewpoint that the initial intracellular deposition of CaCO3 onto a preformed organic matrix is considered to be an animal rather than a plant characteristic.
Lizard Malaria in Georgia*
Authors: JORDAN HELEN B.
Published: May 2007

SYNOPSIS. South of latitude 32°, where adequate samples were taken, both Sceloporus undulatus and Anolis carolinensis were infected with Plasmodium fioridense Thompson and Huff, but with varying frequency. Data resulting from general surveys made in two coastal islands, Jekyll and Sapelo, and from 11 counties in south and southwest Georgia showed 62 of 1,325 or 4.7% of Sceloporus and 106 of 846 or 13% of Anolis to be positive for P. fioridense. The Fargo‐Okefenokee Swamp Area, including Echols and Clinch Counties, was designated as a special study area during the period of 1959–1963, during which time monthly collections of lizards and mosquitoes were made for transmission experiments. In this area, 104 of 2,232 or 4.7% of Sceloporus and 510 of 1,502 or 34% of Anolis were positive for P. fioridense. During the first 3 years (1959–1961), the rate of infection in Anolis was about 46% as compared to 6% in Sceloporus from the same area during the same period. In 1962 the frequency of occurrence in Anolis dropped to 24% (85 of 358) and in Sceloporus to 3.3% (15 of 448). In 1963 there was a further drop to 17% in Anolis (60 of 353) and to 2% in Sceloporus (11 of 514). Thus the incidence was from 3 to 10 times higher in Anolis than in Sceloporus in this area. There is a marked increase in new infections in Anolis during late summer and fall indicating a period of parasite transmission.

Local mosquitoes, Aëdes atlanticus‐tormentor, A. triseriatus, Psorophora confinnis, P. ferox and Mansonia perturbans, fed on infected lizards and kept at 25–30°C, were all negative. One of 80 Aëdes aegypti showed 1 oocyst and negative salivary glands. Four of 70 Culex territans had 23, 1, 16 and 2 oocysts, but negative glands 31 days following an infective blood meal from Sceloporus. Culex quinquefasciatus (225 dissected) had 2 infections of 1 and 3 oöcysts and negative glands. One of 3 Culex sp. had 70 oocysts and negative glands. No transmission experiments were successful. Under the conditions of testing, when Anolis and Sceloporus were exposed to mosquitoes at the same time, mosquitoes preferred to teed on Sceloporus.
Cultivation of the Peritrich Telotrochidium henneguyi in Axenic and Non‐Axenic Media*
Authors: FINLEY HAROLD E. , McLAUGHLIN DAVID
Published: May 2007

SYNOPSIS. Telotrochidium henneguyi was cultured axenically. The major nutrients in medium T‐3 were liver extract (1:20 National Biochemicals Co.), hydrolyzed yeast nucleic acid, glucose, and dl‐β‐hydroxybutyric acid; these were fortified with phosphate buffer, EDTA, and penicillin. The supplements were: 18 amino acids, 7 vitamins, 10 salts supplying trace‐metals; uridylic, cytidylic, guanylic, and adenylic acids; thymidine‐5‐diphosphate, nicotinamide mononucleotide, and choline. Optimum conditions for axenic cultivation were obtained with phosphate buffer 2 × 10−1M, penicillin 5,000 U.S.P. units/ml, 23°C, pH 6.8. A monoxenic maintenance medium (“T‐broth”) allowed prolific growth and produced trxmendous populations. It was composed of Bacillus cereus in an aqueous broth‐concoction of Proteose‐peptone, Cerophyl, and wheat kernels. Axenic T‐3 medium supported serial subculture; yields of peritrichs were comparable to those in T‐broth. Axenic yields were poorer in medium lacking the T‐3 supplemenits but containing the major nutrients fortified with acid‐hydrolyzed gelatin, serine, riboflavin, EDTA, CaCL, FeCI3, KCI, MgSO4·7 H2O, phosphate buffer, and penicillin. For rapid axenination, excystment was induced by vibrating encysted peritrichs ∼ 30 sec in a Vortex Jr. mixer. Freshly excysted animals were washed by centrifugation. A salt solution, not distilled water, was used for washing inoculants. Inocula consisting of 1 × 103 or more animals were obtained by conventional centrifuge methods.

Extension of this investigation to construction of a chemically defined medium is discussed.
A Hyper‐Parasite of Iodamoeba buetschlii from the Rhesus Monkey, Macaca mulatta, and the Domestic Pig
Authors: RAY H. N. , BANIK D. C.
Published: May 2007

SYNOPSIS. So called “inclusion” bodies in the cytoplasm of Iodamorba biretschlii cysts from rhesus monkeys (Mocaca mulatta) and domestic pips appeared to be hyper‐parasites of unknown taxonomic position (posubly a protozoon or a fungus), They had a dot‐like Feulgen‐positive nucleus, cytoplasmic alkaline phosphatase, periodic acid Schiff ‐positive material, and proteins reacting to the bromophenol blue test. Their nuclei appeared to divide by budding and ultimately to produce six to eight minute, round or oval spore‐like bodies. The Iodamoeba cysts mntaining these bodies had highly vacuolated cytoplasm, suggesting that the hyper‐parasites had a degenerating effect on their host.
The Amoeba‐to‐Flagellate Transformation in Tetramitus rostratus. I. Population Dynamics*
Authors: OUTKA DARRYLL E.
Published: May 2007

SYNOPSIS. Thirty to 80% of Tetramitus rostratus amoebae were induced to transform into the flagellated stage. The procedure involved growth in a dilute hydrolyzed casein medium with living Escherichia coli dispensed in microdrops approximately 0.5 mm3 in volume and sealed in a slide‐depressionchamber. Single amoebae placed in such microdrops did not transform until growth and division had produced a population density of 100 amoebae/mm3. Flagellation then began and proceeded rapidly.

Analysis of growth and transformation in microdrops of different sizes but with equal numbers of amoebae, or of microdrops of the same size but different numbers of amoebae, suggested that the amoebae themselves were elaborating substances into the medium which brought about their own transformation. The effects of bacteriostasis induced by a variety of antibiotics did not clearly rule out a bacterial contribution to the factors causing transformation. Osmotic effects within physiological limits did not play any demonstrable role in inducing the response.

It was concluded that transformation of amoebae to flagellates involved rapid growth and subsequent undetermined changes in the medium.
The Morphology and Biology of Pyxicola nolandi n. sp. (Ciliata, Peritrichida, Vaginicolidae)*
Authors: FINLEY HAROLD E. , BACON ARTHUR L.
Published: May 2007

SYNOPSIS. Pyxicola nolandi, n. sp., is a loricate peritrich favored by clean pond water. The yellowish‐brown lorica measures 74 × 25 μ, on the average; supported by a noncontractile stalk, it resembles a vase with a slightly curved neck bearing an oblique opening. The stalk, ∼ 13 × 6 μ, is marked by vertical lines which give it a corrugated appearance. The bluish‐gray translucent truncated body is protrusible beyond the lorica's opening, averages 87 × 15 μ, and is characterized as follows. An expansive sphincter collar that extends into a narrow shelf; 3 rows of concentrically spiralling peristomial membranes; prominent “soie de Lachmann” visible when peristomial region expands; a slightly lobulated discshaped operculum originating on the ventro‐lateral surface of the peristomial collar, averaging 15 μ in diameter, and overhanging the edge of the lorica when the body extends; one contractile vacuole; C‐shaped macronucleus; micronuclcus ∼ 6 times 3 μ

Large populations were found in June, July, and August, attached to the alga Rhizoclonium hieroglyphicum and to other kinds of filamentous algae. The peritrich was scarce in winter, but it was found even when the pond was covered with ice, providing that Rhizoclonizm survived in the cold weather.

Some aspects of binary fission, lorica formation, conjugation, environmental pREFERENCES, and maintenance are described. The peritrich was cultivated in laboratory aquaria. Clones were established repeatedly from pond D‐7 and from laboratory aquaria. Loricae were stained successfully with Congo red. Nuclear phenomena were revealed with the Feulgen technique. Silver impregnation was unsuccessful, thus far.
Conjugation Between Two Strains of Blepharisma
Authors: INABA FUMIE
Published: May 2007

SYNOPSIS. Conjugation involving two Japanese strains of Blepharisma, Niigata and Nara, which are considerably different from each other in external morphology, but are rather similar in nuclear configuration, was induced experimentally. Compared with normal conjugations of the two strains, both the Niigata‐ and Nara‐interbred exconjugants show a strikingly high mortality. The possibilities of the occurrence of autogamy and cross‐fertilization are discussed on the basis of the results obtained from observations on living and fixed material.
Laboratory Experiments on the Life Cycle and Ecologic Controls of Rosalina globularis d'Orbigny
Authors: SLITER WILLIAM V.
Published: May 2007

SYNOPSIS. The life cycle of R. globularis is shown to include a Tretomphalus stage identified as T. bnlloides. The life cycle is further complicated by successive asexual division producing typica1 agamonts. A brief synonymy is given for the genus. Basic experiments with light and substrate variation have shown no direct response.
Two New Species of Plistophora (Microsporidea) from North American Fish with a Synopsis of Microsporidea of Freshwater and Euryhaline Fishes
Authors: PUTZ ROBERT E. , HOFFMAN GLENN L. , DUNBAR CLARENCE E.
Published: May 2007

SYNOPSIS. Two new species of Microsporidea, Plistophora salmonae from steelhead and rainbow trout (Salmo gairdntri) and Plistophora crpedianar from gizzard shad (Dorosoma cepedianum) are described. Schizonts to spores of P. cepedianae were found at one time within the same cyst, while only sporonts and spores of P. salmonae were found within the cyst.

An illustrated synopsis of the known Microsporidea of freshwater and euryhaline fishes is given.
Studies on Myxosoma cartilaginis n. sp. (Protozoa: Myxosporidea) of Centrarchid Fish and a Synopsis of the Myxosoma of North American Freshwater Fishes
Authors: HOFFMAN GLENN L. , PUTZ ROBERT E. , DUNBAR CLARENCE E.
Published: May 2007

SYNOPSIS. Myxosoma cartilaginis n. sp. is described from the cartilage of Lepomis macrochirus (bluegill), L. cyanellus (green sunfish) and Micropterus salmoides (largemouth black bass). The development of the parasite is described from naturally infected fish which were held in spore‐free water after infection. The sporoplasm invades cartilage, and becomes a multi‐nucleate trophozoite which forms pansporoblasts, each of which produces 2 to 4 spores. The first spores appear in 7 weeks.

The histopathology in the above fish consists at first of little cellular reaction, but after 4 to 5 months epithelioid granulomas appear around some of the spore masses. Cartilage liquefaction is present around the parasites for at least 5 weeks. Eosinophilic globules are present in cartilage cells adjacent to the lesions. Diffuse infiltration of the spores from the lesions is described.

Of 24 chemicals tested for polar filament extrusion, potassium hydroxide gave the best results.

An illustrated synopsis of the Myxosoma of North American fishes is given. Included is some additional information and illustrations of M. hoffmani Meglitsch, 1963. Also included is a table showing the hosts, site of infection, geographic location, spore and polar capsule sizes.
Biochemical Studies on Irradiated Protozoa. III. Catalase Activity in Tetrahymena pyriformis W*
Authors: ROTH JAY S. , BUCCINO GAYLA
Published: May 2007

SYNOPSIS. The amount, distribution and some properties of catalase activity in Tetrahymena pyriformis W have been determined. The enzyme specific activity is about 10% that of rat liver and is found principally in a particulate fraction that may be sedimented at 1500 X g. The enzyme is insensitive to pH changes but is destroyed by heating above 50°. The effect of catalase inhibitors on the growth, respiration and enzyme activity of the protozoa was investigated. Allylisopropylacetamide, an inhibitor that is effective in preventing catalase synthesis in rats, renders the protozoa more sensitive to irradiation with 500,000 r of γ‐rays.
The Morphology of Blepharisma undulans Stein*†
Authors: KENNEDY JOHN R.
Published: May 2007

SYNOPSIS. Electron‐microscope studies have revealed the ciliature and infraciliature of Blepharisma undulans to include tubular filaments about 24 mμ in diameter. As these filaments pass from the kinetosomes into the surrounding cytoplasm they appear to divide into double helical subfilaments, each with a diameter of about 12 mμ. In the somatic region the ciliary rows are composed of series of paired kinetosomes. Connected with the anterior member of a pair are the cilium and transverse filaments, the posterior member giving rise to the posterior kinetodesmal fiber. From between the two kinetosomes arises the anterior kinetodesmal fiber. The kinetodesmal fiber system is associated with the subpellicular fibril system which lines the area just beneath the pellicle of the animal.

In the oral region a series of these filaments extends from the proximal portion of the adoral zone of membranelle kinetosomes into the cytoplasm. They traverse the oral area to connect with the undulating membrane on the right margin of the mouth. Also present are fibers comparable to the kinetodesmal fibers and transverse fibers of the somatic region. The functional significance of this system is discussed.

The nucleus and nuclear and cytoplasmic inclusions are described, including pigment granules, storage products, the Golgi apparatus, mitochondria and vacuole systems.
Glucose vs. Acetate Metabolism in Euglena*
Authors: COOK J. R. , HEINRICH B.
Published: May 2007

SYNOPSIS. Euglena gracilis strain Z cells cultured in an inorganic medium with glucose as carbon and energy source differ from cells grown on acetate. Over optimal ranges of pH and substrate concentration, both glucose and acetate support essentially the same rates of growth, and mass and protein synthesis. Glucose, however, yields population densities 10X greater than acetate. Furthermore, in adapted cells glucose does not stimulate respiration above endogenous levels, whereas O2 consumption on acetate is 4X greater than endogenous; and acetate‐grown cells have 50% more RNA than glucose‐grown cells.
Cultivation of Three Species of Theileria in Lymphoid Cells in vitro
Authors: HULLIGER LOTTE
Published: May 2007

SYNOPSIS. The intralymphocytic stages of Theileria parva, T. lawrencei and T. annulata have been cultivated for several months in tissue cultures of bovine lymphocytes associated with baby hamster kidney cells. In established cultures the theilerial particles multiplied at about the same rate as the host cells, the percentage of infected cells and the mean number of parasite particles per cell remaining nearly constant.

During mitotic division of the host cell the theilerial body becomes closely associated with the spindle fibres and is pulled apart and distributed to both daughter cells in late anaphase. The single theilerial particles (chromatin) within the theilerial body divide by binary fission; their division is not synchronous with that of the host cell.
Inheritance of Autogamy and the Killer Trait in Euplotes minuta
Authors: SIEGEL R. W. , HECKMANN KLAUS
Published: May 2007

SYNOPSIS. Eight interfertile strains of Euplotes minuta collected from two localities in the Mediterranean Sea are shown to comprise a single breeding system of multiple mating types. One strain regularly passes through autogamy and, in crosses to non‐autogamous strains, preliminary evidence for the genic control of autogamy was obtained. The cytogenetic events of conjugation and autogamy are briefly described. Three strains are “killers.” Killer cells liberate a substance into the surrounding medium which has a lethal effect on cells of other strains called “sensitives.” This substance, “euplotein,” is not produced by sensitives. The inheritance of the killer trait is apparently under the control of a cytoplasmic factor but present attempts to identify the factor microscopically were without success. The discussion stresses the potential usefulness of this species for studies of protozoan genetics and development.
Nuclear Division Without Cytokinesis Followed by Fusion of Pronuclei in Paranotila lata gen. et sp. nov.
Authors: CLEVELAND L. R.
Published: May 2007

SYNOPSIS. Under the influence of ecdysone a uninucleate asexual cell of Paranotila lata gen. et sp. nov. is transformed into a gametocyte in which, as a rule, 8 successive nuclear divisions occur, thus producing 8 male and 8 female pronuclei. No cytokinesis occurs during these divisions. The process should be regarded as a gametogenesis in which only nuclei participate. These gametic pronuclei fuse, male with female, and produce 8 fusion or zygotic nuclei. The cell may now be regarded as a zygote, which soon undergoes plasmotomy, and eventually produces 8 uninucleate, diploid asexual cells. This is the usual course of events. A few exceptions or irregularities have been noted. Throughout gametogenesis, Paranotila is quite indifferent regarding the production of new flagella and axostyles; sometimes they are produced, sometimes they are not.
Host‐Integrated Development in the Amoebidiales*
Authors: WHISLER HOWARD C.
Published: May 2007

SYNOPSIS. Induction of the resistant stage in the Amoebidiales appears to be dependent upon a morphogenetic factor derived from the host animal. This triggering substance is released either at death or ecdysis of the host arthropod. Growth of the epizoon, Amoebidium parasiticum, in both complex and defined media, follows a sporangiospore sporangium pattern. The amoeba‐cyst phase, however, was only noted after crushed host material (Cladocera) was added to the axenically grown thalli. Subsequent tests, evaluated with a quantitative assay, indicate that amoebagenesis is influenced by pH, temperature, condition of the protist, and concentration of the active principle. Commercial “dried daphnia” has consistently yielded an active extract. A large number of complex and simple materials has been screened for activity, and only extracts of ground crab show promise as an alternate source. The amoebagenic factor is heat stable, relatively small, and not soluble in ether, acetone or chloroform. Paper chromatography with polar solvent systems yields a single active band, and this is the best evidence that amoebagenesis is induced by a single, rather than a multiple factor. Paramoebidium, the second genus in this obscure order, undergoes amoebagenesis at ecdysis of the host. The possibility that Amoebidium and Paramoebidium are simply different growth forms of the same protist is discussed.
The Life Cycle and Morphology of the Apostomatous Ciliate, Hyalophysa chattoni n. g., n. sp.*
Authors: BRADBURY PHYLLIS CLARKE
Published: May 2007

SYNOPSIS. A new apostome ciliate was discovered in collections at Friday Harbor, Washington and the San Francisco area. All stages of the life cycle were studied in both living and stained condition.

Dormant encysted stages (phoronts) occur on the gills of Pagurus hirsutiusculus. Excystation occurs in synchrony with the molting of the host yielding the trophic stage (trophont), which feeds on the exuvial fluids trapped in the crab's cast‐off exoskeleton. The trophont becomes greatly enlarged as a result of feeding, and the cytoplasm and organelles become compressed into a thin cortical layer. Each fully grown trophont encysts (becoming a tomont) as a prelude to repeated binary fission, which results in the release of actively motile offspring (tomites). These disperse and promptly resume the encysted phoront stage on the host's gills.

The Chatton‐Lwoff silver impregnation method revealed that all stages of the life cycle have nine somatic kineties. In the trophont stage they are accompanied by an anterior ventral field of scattered clumps of kinetosomes. During conjugation the partners attach by their ventral surfaces between kineties 1 and 9 and at the left of the ventral field.

The tomite stage was stained with Protargol. In addition to the characteristic features of the foettingeriid tomite also revealed by the Chatton‐Lwoff method, Protargol revealed the following heretofore undescribed morphological features: a short row of kinetosomes immediately anterior to the ogival field; a line paralleling the left margin of the field; the continuity of kinety 8 with falciform field 8; the entrance of kinety 9 into the mouth and its ending against the rosette (an enigmatic organelle characteristic of Foettingeriinae).

Feulgen stains showed that the chromatin in the macronucleus is dispersed in aggregates whose size and number vary with the stage of the life cycle. The major period of chromatin synthesis appears to be during the early tomont stage, when Feulgen‐positive material increases visibly in amount and intensity of staining.

This apostome ciliate was characterized as a new genus on the basis of the infraciliature of the trophont stage, its conjugation with ventral surfaces appressed, and its life cycle. It is named Hyalophysa (hyalo = glassy, physa = bubble) chattoni.
Haemogregarina faiyumensis n. sp. in the Toad Bufo regularis in Egypt*
Authors: MANSOUR NOSHY S. , MOHAMMED A. H. HELMY
Published: May 2007

SYNOPSIS. Haemogregarina faiyumensis n. sp., a parasite of toads, Bufo regularis, in Faiyuni Province, Egypt, U.A.R., is described. In a survey of 689 toads from various localities in Cairo, Giza and Faiyurn provinces, only 3 out of 13 toads from Kom O Shim near Faiyum were infected. This species, known only by blood forms (most probably gametocytes) of two different staining reactions, is 13‐17 μ long and 4‐5 μ wide, with an average of 15.5 × 4.5 μ. The nucleus is typically subcircular and 3‐5 × 3–5 μ, with an average of 4.5 × 3.9 μ.
Endogenous Cycle of the Swine Coccidium Eimeria debliecki Douwes, 1921*
Authors: VETTERLING JOHN M.
Published: May 2007

SYNOPSIS. A pure strain of Eimeria debliecki (University of Illinois strain A) established from a single oocyst was used to determine the endogenous cycle. Young parasite‐free pigs 2 weeks to 3 months old were used throughout the study.

The endogenous cycle was found to take place in the small intestine where the parasites were located in the distal portion of the striated simple columnar epithelial cells of the villi. The first generation schizonts were found in only the jejunum (15% of small intestine). The second generation schizonts and gametes occurred in the jejunum and ileum (70% of small intestine), a slight posterior progression occurring with each stage. The entire cycle required 6.5 days.

The schizogonous cycle comprised 2 generations. The first generation schizonts required 2.5 days to reach maturity, measured 8‐12 μ, contained 16 merozoites measuring 12‐15 μ and had a polar residual mass. The second generation schizonts required 2 days to reach maturity, measured 13‐16 μ, contained 32 rotund merozoites measuring 6–8 μ, and had only a few granules of residual material.

Gametogony took place in 1.5 days. The macrogametes measured 12‐16 μ, and the microgametocytes measured 9‐14 μ with microgametes measuring 5–6 μ.
Carbonyl Compounds Produced by Cryptomonas ovata var. palustris*
Authors: COLLINS R. P. , KALNINS K.
Published: May 2007

SYNOPSIS. Some neutral carbonyl compounds synthesized by Cryptomonas, ovata var. palustris were identified as methanal, ethanal, 2‐propanone, pentanal, and heptanal by means of thin‐layer chromatography, gas chromatography and infrared spectroscopy.
“Spheroplasts” Prepared from Euglena gracilis by Proteolysis*
Authors: PRICE C. A. , BOURKE MARION E.
Published: May 2007

SYNOPSIS. Protoplast‐like, osmotically‐sensitive bodies were prepared from Euglena gracilis by treatment with a crude preparation of proteolytic enzymes. These spheroplasts were free of pellicles to varying degree as viewed by phase‐contrast microscopy and were more easily ruptured than were untreated controls. The spheroplasts retained D‐lactate dehydrogenase and acid phosphatase activity, but with altered permeability characteristics.
Amebic Parasites of Fishes*
Authors: NOBLE ELMER R. , NOBLE GLENN A.
Published: May 2007

SYNOPSIS.Entamoeba molaen. sp. was found in the hindgut ofMola molacollected from the coast of southern California. The trophic stages are actively motile and contain numerous food vacuoles. The nuclear peripheral chromatin is usually conspicuous. A subperipheral crescent of granules is the most distinctive feature of the nucleus. The endosome is eccentric and often surrounded by a periendosomal ring. Measurements: cell body 16.4 × 22.9 μ nucleus 4.8 μ in diameter. Cysts were not seen. We believe that few amebas have been described from fishes because few fishes have been examined for amebas.
Folate Cofactor Biosynthesis by Plasmodium berghei. Comparison of Folate and Dihydrofolate as Substrates*
Authors: FERONE ROBERT , HITCHINGS GEORGE H.
Published: May 2007

SYNOPSIS. The ability of Plasmodium berghei to convert folate and dihydrofolate to folinate in vitro was investigated. Neither parasitized mouse erythrocytes nor free parasites synthesized more than trace amounts of folinate from folate under a wide variety of experimental conditions. Since disrupted cell preparations were no more efficient than whole cells, permeability barriers did not seem to be involved. However, dihydrofolate was a good substrate for the synthesis of folinate by uninfected and parasitized erythrocytes, and by free parasites. The reaction by parasitized erythrocytes required NADPH and dihydrofolate, and was inhibited by pyrimethamine, indicating the presence of dihydrofolate reductase in P. bergkei. It was postulated that P. berghei cannot utilize folate directly, since these experiments indicate that the cells lack a folate reductase. This finding is consistent with the hypothesis that plasmodia synthesize folate cofactors de novo, and do not utilize exogenous folates.
Haemoproteus palumbis sp. nov. (Sporozoa, Haemosporina) of the English Wood‐Pigeon Columba p. palumbus
Authors: BAKER J. R.
Published: May 2007

SYNOPSIS. Haemoproteus palumbis sp. nov. is described from the English wood‐pigeon, Columba p. palumbus. Its pigmented gametocytes inhabit erythrocytes and resemble those of H. columbae (in C. livia) but may be slightly longer and narrower. It is characterized by having oval or slightly lobed, not elongate, schizonts in endothelial cells of lung and heart, a prepatent period of 14 days, and a sporogonic cycle in the hippoboscid fly Ornithomya avicularia lasting 6 1/2–7 days. H. palumbis sp. nov. cannot infect C. livia but can infect a small proportion of individuals of Pseudolynchia canariensis, the vector of H. columbae.
The Occurrence of Sarcocystis sp. in the Dog
Authors: SAHASRABUDHE VASANT K. , SHAH HARISH L.
Published: May 2007

SYNOPSIS. Cysts of Sarcocystis sp. are described from a dog. They are spherical to elongate, 110–250 μ in diameter, and contain numerous crescentic trophozoites measuring 4–5 × 1.5 μ. No septa were seen. This is the first report of Sarcocystis from a domestic carnivore.
Amino Acids as Nitrogen Sources for the Growth of Euglena gracilis and Astasia longa
Authors: BUETOW D. E.
Published: May 2007

SYNOPSIS. Euglena gracilis (bacillaris variety, strain SM‐L1, streptomycin‐bleached) used the following amino adds (10−3 M) as sole nitrogen source for growth on a defined medium: glycine, alanine, valine, leucine, isoleucine, serine, threonine, and glutamic acid. Aspartic acid was used at 10−2 M. Glutamine and asparagine were used at 10−3 M and were better N sources than their parent dicarboxylic amino acids. Not used as sole N source for growth were phenylalanine, tyrosine, tryptophan, cysteine, cystine, methionine, proline, hydroxyproline, histidine, arginine, lysine, and taurine. Astasia longa (Jahn strain) was more restricted than Euglena and used only asparagine and glutamine as N sources for growth.
Acriflavin Induction of Dyskinetoplasy in Leptomonas karyophilus*
Authors: STUART K. D. , HANSON E. D.
Published: May 2007

SYNOPSIS. Acriflavin concentrations of 0.025 μg/ml and higher were Lo Leptomonas karyophilus in NNN medium to which no ribohad been added, and did not bring about the production of dys plastic forms. Upon addition of 0.4 μg/ml of riboflavin, contions of acriflavin up to 10.0 μg/ml allowed growth and rein the production of up to 86% dyskinetoplastic forms. Under conditions, increasing concentrations of acriflavin decreased the growth rate while increasing the rate of production of dyskinetoplastic forms. The number of dyskinetoplastic forms increased with time while the number of kinetoplastic forms remained approximately constant or decreased due to death. At a concentration of 1.0 μg/ml acriflavin and 0.4 μg/ml riboflavin, growth was primarily due to the production of dyskinetoplastic forms.
Specificity of Glycerol for Dark Growth of Prymnesium parvum
Authors: RAHAT MENACHEM , SPIRA ZIPORA
Published: May 2007

SYNOPSIS. Out of 64 nutrients tested, none replaced glycerol for growth in the dark of Prymnesium parvum. Some metabolites enahanced growth in the light, and in the presence of glycerol also in the clark. Good growth with glycerol could be obtained in the absence of CO2. Survival of cultures in the dark in media without glycerol was prolonged by various nutrients. Thioglycerol in glycerol‐containing media inhibited growth in light and darkness. Apparently Prymnesium parvum has a specific glycerol requirement for dark growth.
Electron Microscopy of the Hypotrich Ciliate Oxytricha platystoma, with Consideration of its Macronuclear Organization
Authors: CHAKRABORTY J.
Published: May 2007

SYNOPSIS. The body of Oxytricha platystoma is covered with 2 membranes, the outer or pellicular membrane and the inner or cytoplasmic membrane. Each cirrus consists of a bundle of 25‐50 cilia. There are 2 macronuclei and 2 micronuclei. The micronucleus is a very small body containing dense Feulgen‐positive material. The macronucleus is an elongated body surrounded by a double membrane. The dense Feulgen‐positive material is embedded in a less dense nucleoplasm. Some larger bodies found inside the nucleus may be nucleoli. There is a single reorganization band in each macronucleus. It consists of a solution plane and a reconstruction plane, and has a total thickness of 1.5 μ. The macronucleus divides amitotically, whereas the micronucleus divides mitotically.
Besnoitia darlingi (Brumpt, 1913) in Panama
Authors: SCHNEIDER CURT R.
Published: May 2007

SYNOPSIS. Besnoitia darlingi (Brumpt, 1913) Mandour, 1965 has been rediscovered in the common opossum Didelphis marsupialis in the Republic of Panama. A strain (D3) has been established in laboratory white mice. Proliferative crescents of the D3 strain are 6.1 (range 6.0‐9.0) by 2.1 (range 1.7‐4.0).

Mouse‐adapted B. darlingi produced acute, fatal infections in white mice, hamsters, 14 marmosets (Saguinus geoffroyi), 2 squirrels (Sciurus variegatoides and S. granatensis), a woolly opossum (Caluromys derbianus) and a four‐eyed opossum (Philander opossum) It probably produced chronic infections (cysts) in 2 wild‐caughtopossums (Didelphis marsupialis) and one lizard (Ameiva ameiva). Animals in which induced infection could not be found after inoculation with trophozoites of mouse‐adapted B. darlingi were: 2 adult and 2 new‐born guinea pigs, laboratory rats, 1 night monkey (Aotus trivirgatus), 2 rhesus monkeys (Macacca mulatta), one iguana (Iguaanaiguana) and 2 baby caimans (Caiman sclerops).
Electron Microscopic and Histochemical Studies of Sporozoite Formation in Plasmodium berghei*
Authors: VANDERBERG JEROME , RDODIN JOHANNES , YOELI MEIR
Published: May 2007

SYNOPSIS. Observations were made on the differentiation of fine structure during sporogonic development of Plasmodium berghei. The oocyst in the process of sporozoite formation is an encapsulated structure 30‐40 μ in diameter. It typically develops while in an extracellular position, attached to the basement membrane of the mosquito midgut and projecting into the mosquito hemocoel. Occasionally, however, ookinetes passing thru the midgut epithelial cells may become impacted within a cell so that the resulting oocyst develops intracellularly.

Each oocyst has a large differentiating region, the sporoblastoid body. This body contains large dividing nuclei which are Feulgenpositive, and a cytoplasm which includes mitochondria, dense rodlike structures, cytoplasmic membranes, cisternae and vacuolar structures, Golgi material, and ribosomes which are both free and membrane‐associated.

Sporozoite budding takes place along the surface of the sporoblastoid body. Bits of a new membrane condense under the plasma membrane which bounds the sporoblastoid body. These 2‐membraned sites then bulge out, continue to elongate, and eventually become sporozoites. The various nuclear and cytoplasmic components of the sporoblastoid body are passed into the sporozoites during their elongation. In addition, the sporozoite develops a system of elogate, subpellicular microtubules, possibly contractile in function. The pellicle of the sporozoite is broken by an opening, the cytostome (micropyle). The anterior end is truncate.
Some Blood Sporozoans from East African Reptiles*
Authors: BALL GORDON H.
Published: May 2007

SYNOPSIS. Six hundred and forty‐one lizards belonging to 28 species, and 29 snakes belonging to 12 species from East Africa were examined for blood sporozoans. Eight species of lizards and 4 of snakes were positive. Tissue phases were seen in some infections; no proven arthropod vectors were found. Parasites are described from previously unreported hosts; new host records, and new stages in the life histories of previously named parasites are reported. The sporozoans belong to the genera Plasmodium, Haemoproteus, Haemogregarina or Hepatozoon, and probably Pirhemocyton. Reasons are given for the inadvisability of establishing new species of some of these on the basis of blood stages alone.
Calcium and Phosphorus Accumulation in Spirostomum ambiguum
Authors: JONES ALICK R.
Published: May 2007

SYNOPSIS. Spirostomum ambiguum is known to contain Ca phosphate as apatite. Tracer experiments with 32P and 45Ca showed that much of the Ca that enters the animal is inexchangeable. About 20% exchanges in the 1st few days but after 42 days only 50% of the original isotope content has been lost. This process seemed independent of temperature, Ca and K concentration, and of whether the animals were starved or fed. It is postulated that the firmly bound Ca is in the form of apatite. By use of both isotopes simultaneously it was shown that some of the Ca uptake was linked with phosphate uptake. However, there appear to be at least one, probably 2 compartments of Ca uptake independent of phosphate uptake. The experiments suggest there being in all 3 compartments of Ca uptake: one firmly bound as apatite; one slightly less firmly bound in some other form (perhaps carbonate); and a last freely exchangeable fraction. The P was found in 2 compartments: one bound to Ca; the other freely exchangeable.

Autoradiography and histochemical tests localized the Ca phosphate deposits in the “endoplasm”, the ectoplasm and nuclear material being free of such deposits. Identification of these deposits in electron micrographs is discussed. It is suggested that these deposits may be waste products possibly derived from mitochondri***al accumulations.
Distribution of the DNA and the DNA‐Histone Antigens in the Nuclei of Free‐Living and Parasitic Sarcomastigophora
Authors: STEWART JOHN M. , BECK J. SWANSON
Published: May 2007

SYNOPSIS. Sixty‐seven species of the subphylum Sarcomastigophora were stained with 2 human antinuclear antibodies to detect the corresponding nuclear antigens, using the indirect immunofluorescence technic. One antinuclear serum contained an antibody to DNA and the other an antibody to DNA linked to histone (DNA‐H). Results were classified according to the revised classification of the Society of Protozoologists' Committee on Taxonomy and Taxanomic Problems (1964). The DNA antigen was detected in the nuclei of all species studied. The DNA‐H antigen was found in all the freeliving species examined, but it was not present in any of the 40 parasitic species tested.

The free‐living species of Sarcodina studied represented the orders Amoebida (families Amoebidae, Mayorellidae) and Actinophryida. Parasitic species tested were all from the Amoebida.

Within the Mastigophora, free‐living species were examined from the orders Cryptomonadida, Euglenida, Volvocida, Dinoflagellida, Kinetoplastida (suborder Bodonina), and Rhizomastigida. Parasitic species studied represented the orders Kinetoplastida (suborder Trypanosomatina), Trichomonadida and Rhizomastigida.

It is suggested that the absence of the DNA‐H antigen in parasitic species is perhaps linked with the inability of these species to survive in a free‐living environment.
A Cold Storage Technic for Studying Excystation of Eimeria tenella*
Authors: LOTZE JOHN C. , LEEK ROBERT G.
Published: May 2007

SYNOPSIS. Activities of sheep coccidia in stages of in vitro excystation, and of Eimeria tenella removed in stages of excystation from the chicken were arrested by lowering the temperature of the parasites; in a cooled condition, the parasites remained apparently unchanged for at least 1‐2 days. When transferred later to the warming stage of the microscope, they quickly resumed excystation. A cold storage technic for E. tenella was developed. The technic might also help in studying other gastrointestinal parasites and might also provide material for classroom work.
Acquired Resistance to Babesia divergens in Experimental Calves
Authors: JOYNER L. P. , DAVIES S. F. M.
Published: May 2007

SYNOPSIS. One intact and 2 splenectomized calves were infected with Babesia divergens and the persistence of the parasites in the blood was followed by periodic subinoculations into susceptible splenectomized calves. After periods varying from 3–7 years the parasites failed to be demonstrable by this method. When the immunity of the animals was challenged by the intravenous injection of blood containing Babesia divergens, they were all resistant to reinfection. These observations add support to the suggestion that sterile immunity may play a part in the resistance of cattle to reinfection with B. divergens.
Patterns of Methionine and Lysine Biosynthesis in the Trypanosomatidae During Growth*
Authors: GUTTMAN HELENE N.
Published: May 2007

SYNOPSIS. Nine Crithidia spp., 2 Blastocrithidia spp., 3 Leptomonas spp. and 2 Trypanosoma spp. were tested for ability to synthesize methionine and lysine during growth.

A prerequisite for methionine biosynthesis is an inordinately high level of folic acid (0.1 mg/100 ml) in the medium. Crithidia factor‐type unconjugated pteridines cannot spare this requirement. Since the methionine‐synthesis factor is still present after acid hydrolysis which destroys folic acid, the factor is either a breakdown product of folic acid or an impurity in the commercial product. All save C. fasciculata var. noelleri and C. from Syrphid could synthesize methionine from homocysteine thiolactone.

None of the organisms synthesized lysine from α‐aminoadipic acid (AAA), thus ruling out the existence of the AAA pathway for lysine synthesis in the Trypanosomatidae. Nine of the organisms synthesized lysine from a mixture of LL‐ and meso‐α,e‐diaminopimelic acid. Since both LL‐ and meso‐DAP are intermediates in the biosynthesis of lysine by the DAP pathway (LL‐DAP→meso‐DAP→lysine) and since decarboxylation of either LL‐ or meso‐DAP could result in formation of lysine, pure meso‐DAP was tested and found active. Thus at least the terminal portion of the DAP pathway for lysine synthesis exists in these true animal cells. Statements about absence of ability to synthesize lysine in animal cells and consequent evolutionary interpretations will therefore require revision.