bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructure of the Giant Amoeba Pelomyxa palustris*
Authors: DANIELS EDWARD W. , BREYER EVELYN P.
Published: May 2007

SYNOPSIS. The ultrastructure of the herbivorous amoeba Pelomyxapalustris was studied. Nuclear division is not understood in this amoeba, and evidence for the method of nuclear division was sought. This species typically has many spheroidal nuclei which are similar within a given cell. However, some amoebae from our collections differed from this common type in both the number and structure of their nuclei. This suggested stages associated with nuclear division. One current hypothesis of nuclear division in this organism is that of nuclear budding. Our evidence is more in accord with this method than with mitosis.

The cytoplasm contained no mitochondria, Golgi bodies, contractile vacuoles or crystals. Most amoebae had 2 types of bacteria (bacteroids or endosymbionts) in their cytoplasm; a separate vesicle enclosed each of these. Characteristically, only 1 type of bacterium (Bn) surrounded the nucleus. Another type (B) was found elsewhere in the cytoplasm. Also in the cytoplasm were the following: food vacuoles enclosing various algae, relatively clear vacuoles and vesicles, glycogen, various electron‐opaque particles, and occasional microtubules. The plasmalemma was smooth, lacking the external fringe which characterizes other large fresh‐water amoebae.
Pantothenic Acid Metabolism During Avian Malaria Infection: Pantothenate Kinase Activity in Duck Erythrocytes and in Plasmodium lophurae*
Authors: BENNETT THOMAS PETER , TRAGER WILLIAM
Published: May 2007

SYNOPSIS. The initial enzymatic reaction in the pathway of coenzyme A genesis from pantothenic acid, i.e., the conversion of pantothenic acid to phosphopantothenic acid catalyzed by pantothenic acid kinase, was found in extracts of avian erythrocytes but not in extracts of Plasmodium lophurae or intact parasites. The activity of the kinase was significantly higher in extracts prepared from normal duck erythrocytes than those infected with P. lophurae. The apparent absence of pantothenic acid kinase in P. lophurae is corroborative support for nutritional studies(7,9) which suggest that the avian malarial parasite is dependent for its supply of coenzyme A on the host cell.
Fine Structure of Sporozoites of Eimeria nieschulzi*
Authors: COLLEY FREDERICK C.
Published: May 2007

SYNOPSIS. An electron microscope study of sporozoites of Eimeria nieschulzi Dieben, 1924 revealed that they have a pellicle which is thickened at the anterior end to form 2 polar rings. Radiating posteriorly from the rings, directly beneath the pellicle, are approximately 25 microtubules which may aid in support and locomotion of the sporozoite. Within the polar ring is a dense conoid. Numerous toxonemes extend posteriorly from the area of the conoid. Two paranuclear bodies are present and some toxonemes are closely associated with the anterior body. Numerous ribosomes, bodies containing granular material, and osmiophilic vesicle bounded bodies are also present. Each sporozoite has a single nucleus with a diffuse karyosome and distinct nuclear double membrane.
The Fine Structure of the Gametocytes of an Adeleine Haemogregarine
Authors: BAKER J. R. , LAINSON R.
Published: May 2007

SYNOPSIS. Gametocytes of an unidentified haemogregarine (Sporozoa, Telosporea, Coccidia, Eucoccida, Adeleina, Haemogregarinicae) from the frog Rana montezumae were examined by light and electron microscopy. The fully‐grown gametocytes lay in a vacuole in the erythrocyte, surrounded by a sheath which was probably of parasitic origin. The gametocytes were bounded by a pellicle of 2 unit membranes, beneath which lay a ring of small longitudinal fibrils. At the anterior end there were 2 concentric layers of larger longitudinal fibrils, arranged in a truncated cone, lying between the pellicle and the cytoplasm of the parasite. The cytoplasm contained a few small mitochondria, many inclusions resembling lysosomes, and small vacuoles; there were also 2 larger, anterior inclusions, which did not appear to run to the tip of the organism. Numerous ribosomes were seen, but no endoplasmic reticulum. The single nucleus contained discrete, dense, granular masses, perhaps deoxyribonucleoprotein, and was apparently limited by only a single membrane.
Incorporation of Tritium from Thymidine‐methyl‐H3 into DNA, RNA, Lipids and Protein in Logarithmic and Stationary Phase Tetrahymena pyriformis, Strain W*
Authors: ALBACH RICHARD A.
Published: May 2007

SYNOPSIS. Numerous reports may be found in the literature on cytoplasmic and non‐DNA utilization of tritium from H3‐thymidine. Such reports underscore the need to clarify the metabolic fate of H3‐thymidine. This investigation outlines the fate of thymidinemethyl‐H3 (TMH3) in logarithmic phase and stationary phase Tetrahymena pyriformis, strain W. Isotope identification by liquid scintillation spectrometry in chemically derived fractions of log phase cultures grown thruout the initial 48 hours of population growth with TMH3 revealed the majority of the radioactivity (90% of intracellular recovery) to be in the DNA fraction. The remainder of the intracellular label was recovered in the acid soluble fraction, lipid fraction, and a small amount in the RNA and cell residue. On chromatographs, tritium appeared only in the thymine moiety of the nucleic acid derivatives.

Hence in dividing cells, thymidine‐methyl‐H3 is “essentially” specific for DNA at the dosage used although some incorporation into other compounds was detected.

Fractionation of the lipid extract from the above experiment on a florisil column localized most of the label to the triglyceride and phospholipid fractions with some recovery in the cholesterol‐esters.

Similar scintillation counting of the various fractions of early stationary phase cells incubated for the last 48 hours of culture with TMH3 revealed limited tritium distribution in all fractions.
The Sporulated Oocysts of Eimeria illinoisensis n. sp. and of Other Species of Eimeria of the Ox
Authors: LEVINE NORMAN D. , IVENS VIRGINIA
Published: May 2007

SYNOPSIS.The sporulated oocysts of 12 species of Eimeria occurring in the oxBos taurusin the United States are described and differentiated. They areE. alabamensis, E. auburnensis, E. bovis, E. brasiliensis, E. bukidnonensis, E. canadensis, E. cylindrica, E. ellipsoidalis, E. illinoisensisn. sp.,E. subspherica, E. wyomingensisandE. zuernii.Two other species, not yet found in North America, which are recognized as valid areE. pellitaandE. thianethi.The sporulated oocysts ofE. illinoisensisn. sp. are ellipsoidal or slightly ovoid, 24–29 by 19–22 μ with a mean of 26.3 by 20.7 μ; their sporocysts are 13–16 by 6–7 μ with a mean of 15.3 by 6.5 μ. This species was found in 3 cattle from one farm in Illinois.
Untersuchungen über den Stickstoffstoffwechsel von Pansenprotozoen (Entodinium) mittels 14C‐Karbonatinkorporation
Authors: HARMEYER J.
Published: May 2007

SYNOPSIS. Isolated rumen protozoan species (Entodinium) were incubated in vitro with starch, antibiotics and Na214CO3. 14C‐carbonate was incorporated into amino acids of the Entodinium protein. Arginine, aspartic acid, alanine, and glutamic acid had the highest specific activities. Carbonate was incorporated into the TCA‐soluble fraction, into cell polysaccharides, and into ether and acetone extracts of TCA‐precipitates.
Photo‐Assimilation of Acetate by an Obligate Phototrophic Strain of Euglena gracilis
Authors: COOK J. R.
Published: May 2007

SYNOPSIS. Light‐dependent incorporation of acetate occurs in an obligate phototrophic strain of Euglena gracilis (strain L). Assimilation is into all major biochemical fractions. Acetate does not induce operation of the glyoxylate by‐pass as it does in heterotrophic strains; neither does it stimulate oxygen consumption. Acetate will not replace CO2 in phototrophic growth. A number of carbon sources tested would not support growth in the dark, and glucose was not incorporated either in the light or the dark.
Phosphate Metabolism in the Culture Form of Trypanosoma cruzi*
Authors: ROBERTS JOHN F.
Published: May 2007

SYNOPSIS. The uptake, distribution and turnover of phosphorus have been studied for the culture form of Trypanosona cruzi. Following exchange reactions, phosphorus was accumulated at an approximate rate of 1.9 μg/108 trypanosomes/hour in Krebs‐Ringerphosphate. Of 3.8 mg P/g trypanosomes (wet weight), 60% occurred in acid‐soluble, 13% in phospholipid, 22% in nucleic acid, and 5% in phosphoprotein fractions. Acid‐soluble and phosphoprotein fractions incorporated P32 more rapidly than phospholipid and nucleic acid fractions, the phosphoprotein fraction having the highest specific activity by 8 hours of incubation.
Surface Ultrastructure of Some Tests of Recent Foraminiferida from the Dry Tortugas, Florida
Authors: LYNTS GEORGE W. , PFISTER ROBERT M.
Published: May 2007

SYNOPSIS. The surface ultrastructure of 10 species of benthic Foraminiferida from the Dry Tortugas, Florida, has been investigated using an electron microscope. Tests of miliolid Foraminiferida appear to be made up of at least 2 distinct layers. An outermost pavement‐like layer, consisting of a single layer of calcite rhombohedrons, and an underlying “randomly oriented layer” comprise most of the wall thickness. It was possible to differentiate each miliolid species on the basis of a statistical analysis of calcite rhombs making up the pavement‐like layer. Pseudopores were found on the tests of Miliolinella subrotunda (Montagu) and Archaias angulatus (Fichtel and Moll). None of these pseudopores completely penetrated the wall, and all floored in the “randomly oriented layer.” It is believed that these structures are formed at time of calcification, rather than secondarily at some later time.

Calcification in Foraminiferida appears to be a biphasic process similar to that found in most other organisms. Groups of crystals were discernible on surfaces of most porcelaneous and “radiate” calcareous species. This suggests that parallel growth of crystals may be an important process in calcification of many Foraminiferida.

A sieve‐plate was found in a canal paralleling the test's surface in Cymbaloporetta squammosa (d'Orbigny).
A Method for the Mass Collection of Axenically Cultivated Paramecium aurelia*
Authors: SOLDO A. T. , VAN WAGTENDONK W. J.
Published: May 2007

SYNOPSIS. A method is described for the collection of large numbers of axenically cultivated Paramecium aurelia free of contaminating particulate debris. The procedure takes advantage of the fact that the ciliates are negatively geotropic and involves migrating the organisms directly from the culture medium into an overlayer of salt solution of low density. Details are given for the construction of a simple apparatus used to carry out these migrations.
Blood Sporozoans from East African Amphibia*
Authors: BALL GORDON H.
Published: May 2007

SYNOPSIS. Haemogregarines are described from the peripheral blood and in some instances from internal organs of 4 species of frogs from East Africa. The parasites from Hyperolius puncticulatus and from Rana wittei have not been reported previously. The haemogregarine from R. mascareniensis is possibly a young stage of a form previously inadequately described. R. angolensis was parasitized by Haemogregarina theileri and also by an organism of uncertain affinity found mainly in the lung capillaries.
Coccidia (Protozoa: Eimeriidae) of the Alpaca Lama pacos*
Authors: GUERRERO CARLOS A.
Published: May 2007

SYNOPSIS. Three new species of coccidia are described from the alpaca Lama pacos from Peru. These are the first species of coccidia to be named from this host. The oocysts of Eimeria lamae n. sp. are ellipsoidal, occasionally ovoid, 30–40 by 21–30 μ (mean 35.6 by 24.5 μ) with elongate ovoid sporocysts 13–16 by 8–10 μ (mean 15.3 by 8.5 μ). The oocysts of Eimeria alpacae n. sp. are ellipsoidal, rarely ovoid, 22–26 by 18–21 μ (mean 24.1 by 19.6 μ), with ovoid sporocysts 10–13 by 7–8 μ (mean 11.0 by 6.8 μ). The oocysts of Eimeria punoensis n. sp. are ellipsoidal, occasionally ovoid, 17–22 by 14–18 μ (mean 19.9 by 16.4 μ), with ovoid sporocysts 8–11 by 5–7 μ (mean 9.2 by 6.1 μ).
Quantitative Measurement of Paramylum in Euglena gracilis
Authors: COOK J. R.
Published: May 2007

SYNOPSIS. A technic is described for the quantitative assay of paramylum content of euglenoid flagellates. The method relies on the alkaline solubility of paramylum followed by treatment with the anthrone reagent. The intensity of the color developed by paramylum is about 14% greater than that developed by an equivalent amount of glucose. The method is sensitive down to about 10 μg.
Comparative Cultivation of Poultry Coccidia in Mammalian Kidney Cell Cultures
Authors: DORAN DAVID J. , VETTERLING JOHN M.
Published: May 2007

SYNOPSIS. Excysted sporozoites of Eimeria meleagrimitis, E. necatrix, E. acervulina, and E. gallopavonis were inoculated into monolayer cell cultures of bovine, ovine, porcine, and human kidney. E. meleagrimitis developed only in bovine embryonic kidney. Mature schizonts were found in the 11th, 16th, and 20th serial passages, but only immature schizonts were in the 4th and 6th passages. E. necatrix developed to mature schizonts in the 3rd, 4th, 6th, 11th, 16th, and 20th passages of bovine kidney and also to immature schizonts in the 175th and 189th passages of PK‐15 (cell line porcine kidney). Schizonts, however, did not develop in the 140th and 145th passages of CCI‐33 (cloned PK‐15). Neither E. meleagrimitis nor E. necatrix developed in the primary, 1st or 2nd passages of bovine embryonic kidney, primary porcine kidney, 45th and 52nd passages of a human embryonic kidney cell line, or in the primary, 5th and 18th passages of ovine kidney. Eimeria acervulina and E. gallopavonis did not develop in any of the cultures.

E. meleagrimitis and E. necatrix probably completed only one asexual generation in culture. The structure of mature schizonts of both species differed greatly from those in the natural host. Schizonts of E. meleagrimitis present at 48 hours were small (13–18 by 12–14 μ) and contained only 12–28 merozoites that were 3.2–3.8 μ long. At 48 hours, E. necatrix schizonts were 15–18 μ in diameter or less and contained only 15–20 merozoites (2.0–3.5 μ long); at 96 hours they were 50–70 by 10–35μ and contained either hundreds of small merozoites (2.0–3.5 μ long) or a lesser number of larger merozoites (9–11 μ).
Development of First‐Generation Schizonts of Eimeria bovis in Cultured Bovine Cells
Authors: FAYER RONALD , HAMMOND DATUS M.
Published: May 2007

SYNOPSIS. Monolayer primary and secondary cultures of embryonic bovine kidney, spleen, intestinal and testicle cells, and secondary cultures of embryonic bovine thymus, maintained in lactalbumin hydrolysate, Earle's balanced salt solution and ovine serum were observed for a maximum of 21 days after inoculation of E. bovis sporozoites. The sporozoites entered the cells in all of these cultures but underwent development only in primary cultures of kidney and intestinal cells and in secondary cultures of kidney, spleen, thymus, intestinal, and testicle cells. In acellular media, the sporozoites retained motility no longer than 21 hr. In the cell cultures, free motile sporozoites were seen for as long as 18 days after inoculation. Sporozoites entered cells anterior end first; the process of penetration required a few seconds to about a minute. Sporozoites were also observed leaving host cells. Intracellular sporozoites were first seen 3 min after inoculation; they were observed at various intervals up to 18 days after inoculation. In transformation of sporozoites into trophozoites a marked change in size and appearance of the nucleus took place before the change in shape of the body occurred. Trophozoites were first found 7 days after inoculation, multinucleate schizonts after 8 days, and schizonts with merozoites after 14 days. Schizonts containing merozoites were seen only in kidney, spleen, and thymus cells. The mature schizonts were smaller and represented a much lower proportion of the total number than in comparable stages of infections in calves. Schizonts with many nuclei occurred in intestinal cells; the most advanced stage seen in testicle cells was the binucleate schizont. Nuclear and cytoplasmic changes were observed in the infected cells.
Life Cycle and Host Specificity of Eimeria callospermophili Henry, 1932 From the Uinta Ground Squirrel Spermophilus armatus*
Authors: TODD KENNETH S. , HAMMOND DATUS M.
Published: May 2007

SYNOPSIS. Eimeria callospermophili was found in 6 species of ground squirrels and the white‐tailed prairie dog. The hosts included Spermophilus armatus from Utah and Montana, S. richardsoni from Montana and Wyoming, S. beecheyi from California, S. lateralis and S. variegatus from Utah, and S. tridecemlineatus and Cynomys leucurus from Wyoming. Infections were generally transmissible from each species of ground squirrel to S. armatus and S. richardsoni. Oocysts from C. leucurus caused infections in S. armatus and S. richardsoni. No infections were found after inoculation of E. callospermophili oocysts into least chipmunks (Eutamius minimus), Mongolian gerbils (Meriones unguiculatus), or laboratory rats; however, excystation occurred in these animals. Resistance to infection did not develop in S. armatus, S. richardsoni, or S. variegatus, but did occur after 5 or more infections in S. lateralis. Eimeria callospermophili had little or no effect on the host in S. armatus, S. lateralis, or S. variegatus, but caused bloody diarrhea in severely infected individuals of S. richardsoni.

The oocysts had an oocyst residuum consisting of several distinct bodies, which later coalesced to form a large homogeneous body. Each sporozoite had an unusually large refractile body. In experimentally infected specimens of S. armatus the prepatent period and patent period lasted for 5 and 9 days, respectively. Mature 1st‐generation schizonts, first seen 2 days after inoculation, had 8–12 merozoites. Mature 2nd‐generation schizonts, first seen 3 days after inoculation, had an average of 18 merozoites which were smaller than those of the 1st generation. Mature gametes were 1st seen 4 days after inoculation. Mature microgametocytes were only slightly larger than mature macrogametes.
Intracellular Development of the Microsporidan Glugea anomala Moniez in Hypertrophying Migratory Cells of the Fish Gasterosteus aculeatus L., an Example of the Formation of “Xenoma” Tumors
Authors: WEISSENBERG RICHARD
Published: May 2007

SYNOPSIS. The conclusion drawn in 1921 that the large nuclei in the cytoplasmic cortex of Glugea cysts are not vegetative nuclei of the microsporidan but nuclei of the hypertrophied host cell was based on the discovery of early developmental stages in the mesenchyme of stickleback larvae experimentally fed Glugea spores. This observation had been made on serial sections from experiments done in 1912. The intracellular development of the microsporidan could be followed up in this material only thru the 1st stages of schizogony. Renewed infection experiments, done still in 1921 on a much broader basis, have fully confirmed the previous findings, as briefly stated in 1922. On this material, the intracellular development of G. anomala has been followed up in recent years from uninucleate host cells 7 μ in diameter, interpreted as wandering cells in the mesenchyme, until they became macroscopic multinucleate cysts, in which schizogony and sporogony of the microsporidan produced innumerable vegetative stages and spores of Glugea. The details of the developmental processes are described in the present paper.

The multinucleate host cell and the intracellular parasites together form one of the symbiotic complexes for which the term “xenom” or “xenoma” has been used by me since 1949. By a sequence of amitotic nuclear divisions, the uninucleate host cell in the Glugea xenomas of Gasterosteus becomes plurinucleate in contrast to the usual structure of other xenomas of fish.

Already in 1921, I thought that the host cell in the Glugea xenomas may have phagocytic properties. The observation of accumulation of granules from pigment cells in some of the Glugea xenomas has now verified this supposition.
Patterns of Cortical Stability in Tetrahymena*
Authors: NANNEY D. L.
Published: May 2007

SYNOPSIS. A simplified technic is presented for determining clonal stability patterns for numbers of ciliary rows in Tetrahymena. The technic involves plotting the variance of meridian number against the mean number of meridians. By this procedure strains of different syngens, difficult to discriminate on other grounds, may sometimes be shown to be distinctive.
The Protoplasmic Connection in Volvox
Authors: IKUSHIMA NOBUSHIGÉ , MARUYAMA SETSUKO
Published: May 2007

SYNOPSIS. Electron‐microscopic observations were performed on 2 species of Volvox, one similar to V. globator, the other to V. aureus. The former has distinct protoplasmic connections in the adult coenobium and specific structures, named “medial bodies,” in the connections just at the intersection with the middle lamella. The medial body is disk shaped, about 800 mμ in diameter, and is composed of 3 parts, 2 dense outer layers and an intermediate less dense zone. In the latter species, the connection and medial body were not seen. On the other hand, it was commonly seen in both of them that in younger, dividing gonidia neighboring protoplasts were connected with each other by protoplasmic bridges. The bridges are undoubtedly formed due to incomplete cell separation in the division of a gonidium. The structural difference in the adult coen***bium between the 2 species emerges just after inversion of the coenobium. In the globator type the medial body appears just after inversion, and the connection remains unruptured all thru life. In the aureus type, it seems that the connections are withdrawn or degenerate immediately after inversion. It is discussed whether protoplasmic continuity is really maintained by the connection or not in the freeswimming coenobium of Volvox.
Sporogony of the Swine Coccidium Eimeria debliecki Douwes, 1921*
Authors: VETTERLING JOHN M.
Published: May 2007

SYNOPSIS. A pure strain of Eimeria debliecki isolated from a single oocyst in parasite free pigs was used thruout the study. Oocysts were allowed to sporulate at 3 constant temperatures, 20, 25, and 30 C, and the sporulation process was examined at 12‐hour intervals. A detailed description of the anatomic sequence of sporulation at 20 C is given and illustrated with photomicrographs and line drawings. The sporocysts and sporozoites are also described.
The Effects of Conjugation in Stentor coeruleus
Authors: HARDEN CHARLES M. , HOLLAND TAFFY
Published: May 2007

SYNOPSIS. Culture methods favorable for conjugation in Stentor coeruleus are described and the effects of conjugation on over 12,000 conjugating pairs of S. coeruleus are presented.
Action of Sulfanilamide on Ochromonas malhamensis
Authors: POTTY V. H. , TAMHANE D. V.
Published: May 2007

SYNOPSIS. Sulfanilamide inhibited the growth of O. malhamensis. Sulfanilamide growth inhibition was reversed competitively by PABA and by very high concentrations of folic acid. Folic acid at low concentrations, however, accentuated sulfa inhibition of growth. Vitamin B12, methionine, p‐aminobenzoylglutamic acid and pteroic add were effective to some extent as antagonists of sulfa. A marked reduction in the folate synthesis was accompanied by sulfa growth inhibition. This was restored on growth restoration by PABA, folic acid, vitamin B12 and methionine. The reduction in folate synthesis held for all the folate fractions except one derivative—a formyl poly‐glutamate. Sulfanilamide‐inhibited cells had a considerable activity for in vitro synthesis of folate activity from precursors. ∼75% activity being retained at the 90% growth inhibition level. There was no change in chlorophyll, RNA and DNA contents as a result of sulfa growth inhibition.
Life Cycle and Host Specificity of Eimeria larimerensis Vetterling, 1964, from the Uinta Ground Squirrel Spermophilus armatus1
Authors: TODD KENNETH S. , HAMMOND DATUS M.
Published: May 2007

SYNOPSIS. Eimeria larimerensis was found in 5 species of ground squirrels and the white‐tailed prairie dog. The hosts included Spermophilus armatus from Utah and Montana, S. variegatus from Utah, S. tridecemlineatus from Wyoming, S. lateralis from Utah, S. beecheyi from California and Cynomys leucurus from Wyoming. Oocysts were not present in fecal samples of S. richardconi from Montana, S. lateralis from California or S. columbianus from Washington. This coccidium could not be experimentally transmitted to S. richardsoni; however, patent infections were established in S. armatus, S. lateralis, and S. variegatus. No infections were found after inoculation of least chipmunks (Eutamius minimus), Mongolian gerbils (Meriones unguiculatus), or laboratory rats even tho excystation occurred in these animals. Resistance to infection did not develop during repeated experimental infections of S. armatus, S. lateralis, or S. variegatus. No outward signs of coccidiosis were seen in any of the experimentally infected animals.

In experimentally infected S. armatus, the prepatent period was 5 days, and the patent period lasted 3–7 (mean 6.5) days. The endogenous stages were located in the epithelial cells of the jejunum and ileum. Mature 1st‐generation schizonts, 1st seen 2.5 days after inoculation, contained 16–32 merozoites. Mature 2nd generation schizonts were present 3.5 days after inoculation and contained 22–46 merozoites of a larger size than those of the 1st generation. Gametocytes were 1st seen 3.5 days after inoculation and developing oocysts were present 4 days after inoculation. Macrogametes contained eosinophilic granules which coalesced to form the oocyst wall. Formation of the macrogametes took place around cytoplasmic masses within the microgametocytes.
The Feeding of Amoeba proteus on Paramecium aurelia*
Authors: SALT GEORGE WILLIAM
Published: May 2007

SYNOPSIS. Density of prey (Paramecium aurelia) and predator (Amoeba proteus) were varied while volume of inorganic medium was kept constant. Variations in density of prey had little effect on the rates of feeding and reproduction of the amoebae; but with increasing predator density the amoebae captured the paramecia less rapidly and ingested fewer before dividing, altho division size did not change appreciably. Therefore, amoebae of a low density population with a constant food supply carry more nutritional reserves from generation to generation than do those in a denser population.
Growth and Immunologic Studies on the Culture Forms of Trypanosoma lewisi*
Authors: DUSANIC DONALD G.
Published: May 2007

SYNOPSIS. Culture forms of Trypanosoma lewisi grown at 27 C in a diphasic blood agar medium resemble in structure the stage found in the invertebrate host. Cultures inoculated with approximately 1 × 106 trypanosomes/ml attain maximum populations of 2–7 × 107 organisms/ml after 5–6 days of incubation. The stationary phase persists 6–15 days. The decline of the population is of relatively long duration with approximately 1 × 106 viable organisms/ml present after 90 days. Variations in growth were attributed to the preparation of defibrinated heated rabbit blood incorporated into the culture medium.

With inocula of 3.0 × 105 trypanosomes/ml there was a lag in growth not observed with larger inocula. Trypanosomes incubated at elevated temperatures had altered growth curves compared to organisms at 27 C. Agitation of cultures did not affect the growth or stationary phases, but hastened the population decline.

Heated and unheated 5% (v/v) normal rat serum incorporated in the liquid phase of the medium altered the growth of the organisms. Heated serum caused a decrease in the population and an extended lag phase. The effects on growth were more marked with unheated serum suggesting that both heat‐stable and labile components affect growth.

Antisera from rats injected with live culture forms included in the liquid phase inhibited, while antisera from rats 24 days after infection with the blood stream forms had no effect on the growth of the culture forms. Antisera from rabbits immunized with sonicates of culture forms also altered the growth of the organisms in culture. Rabbit antisera prepared by immunization with sonicates of dividing and non‐dividing blood stream forms had no effect on the in vitro growth. Antisera from animals immunized with rat blood and culture medium were also without effect. The immunologic implications of the data are considered and discussed.
Observations on the Development of Babesia caballi (Nuttall) in the Tropical Horse Tick Dermacentor nitens Neumann
Authors: HOLBROOK A. A. , ANTHONY D. W. , JOHNSON A. J.
Published: May 2007

SYNOPSIS. The development of Babesia caballi (Nuttall) in Dermacentor nitens Neumann was studied in smear preparations and histologic sections of ticks infected with this protozoan parasite. A majority of the parasites in equine erythrocytes ingested by the adult ticks apparently were destroyed. Smal spherical bodies 4–6 μ in diameter were the 1st developmental stages of B. caballi observed in the gut contents of ticks infected with this parasite. These spherical bodies apparently gave rise to clavate (club‐shaped) bodies 10–14 μ long by 4–6 μ wide. The latter developed into large round bodies 12–16 μ in diameter that segmented into vermicular‐shaped parasites, about 8–12 μ long by 2–4 μ wide; some penetrated the gut wall, some invaded other cells of the tick.

In the cells of the Malpighian tubules, hemolymph, and ovaries, the vermicular parasites underwent a secondary cycle of multiple fission, forming vermicules similar to those occurring earlier in the gut. Vermicules that invaded the ova underwent a similar multiple fission cycle during the larval stage of the tick.

Vermicules from the multiple fission cycle that occurred during the period of larval feeding invaded the salivary glands. A multiple fission cycle of increase within these glands resulted in large numbers of small, oval and piriform parasites, 2.5–3 μ, maximum dimension. These parasites became mixed with the salivary secretions, and presumably are the forms injected into the horse by the nymphs as they feed. The small oval and piriform parasites therefore appear to be the infective stage for the horse.
The Life Cycle of Ganymedes oaklandi n. sp., an Acephaline Gregarine of Gammarus fasciatus (Say)*
Authors: JONES IRA
Published: May 2007

SYNOPSIS. Ganymedes oaklandi n. sp. (Ganymedidae) from the intestine of Gammarus fasciatus (Say) is described, and its life cycle is given. In the trophic stage the gregarine is acephaline, with an elongated cylindrical body slightly tapered anteriorly, and is up to 298 × 64 μ. The gametocysts are up to 121 × 99 μ, and are covered with a secreted thick sticky gelatinous coat. The spores are released from the gametocyst by rupturing of the cyst wall. The spore body is spherical, approximately 6 μ in diameter, and has 4 episporal rays about 20 μ long.
Eimeria utahensis sp. n. from Kangaroo Rats (Dipodomys ordii and D. microps) in Northwestern Utah*
Authors: ERNST JOHN V. , HAMMOND DATUS M. , CHOBOTAR BILL
Published: May 2007

SYNOPSIS. The sporulated oocysts of Eimeria utahensis sp. n. from 2 species of kangaroo rats in northwestern Utah are described. The oocysts averaged 42.0 by 39.3 μ, and had rough, yellow‐brown walls, about 3 μ thick. In each sporocyst, a substiedal body was seen beneath the Stieda body; this is the 1st report of such a structure in any Eimeria species. E. utahensis was found in 3.6% of 196 Dipodomys ordii and 19.4% of 36 D. microps. The incidence was higher in young adult than in adult Ord kangaroo rats and lowest in juveniles; in D. microps only adults were infected. The mean prepatent period was 9.8 days. The patent period could not be determined because of apparent reinfections; there was no evidence of immunity.
Development of the Mycetozoan Echinosteliopsis oligospora*
Authors: REINHARDT DONALD J.
Published: May 2007

SYNOPSIS. The mycetozoan genus Echinosteliopsis, resembling the myxomycete Echinostelium in some of its features, is described. The single species, E. oligospora Reinhardt & Olive, forms small sporocarps which consist of a basal disk, stalk and a sporangium with only 1–8 spores. Spores form progressively, not simultaneously, by segmentation. The spores germinate to release non‐flagellate amebae which, in liquid, assume a characteristic broad, fan shape. Each ameba has one or more nuclei. The nucleus is distinctive because of refractile, globular to elongate peripheral bodies which cytochemical tests indicate to be primarily RNA. At the time of nuclear division the characteristic RNA bodies disappear and, as observed with the phase microscope and in stained preparations, optically dense material accumulates in the middle area of the nucleus. Threads, either a spindle or actual chromatin, can be seen attached to the nuclear membrane. The threads separate to opposite poles as the nucleus elongates. During this division process the nuclear membrane apparently remains intact. Synchronous binucleate divisions, as well as a tripolar nuclear division, have been observed. Uninucleate and synchronous binucleate divisions may or may not be followed by cytokinesis. The absence of cell division after nuclear division leads to the production of cells with varying numbers of nuclei. Nuclear divisions in early sporangial stages and in spores have not been observed. The spores are uni‐ to multinucleate. In 8‐spored sporangia and in most 4‐spored sporangia there is a characteristic small “stalk spore” at the apex of the stalk. The stalk spore germinates slowly, if at all, but the larger spores germinate readily. No evidence of a sexual process has been found.
Anodal Contraction of Paramecium Protoplasm*
Authors: MILLER DONALD M. , JAHN THEODORE L. , FONSECA JAMES R.
Published: May 2007

SYNOPSIS. Paramecia immobilized on an agar surface were stimulated with pulses of 2–8 mamps/cm2 with intervals ranging from 1.0 to 1000 msec. High speed cine films (1500‐6000 frames per second) of the animals' responses were analyzed to determine changes in body length and the effects on cilia and trichocysts. At current densities in the range of 1.0 mamp/cm2, rapid ciliary reversal occurred. Above this value the paramecia shortened. This body contraction can be very rapid, resulting in shortening to 95% of the body length in 0.95 msec. At all levels of stimulation, contraction of the body length occurred 1st anodally, then cathodally. Extensive trichocyst extrusion occurred 1st at the anode and later at the cathode at current densities greater than 5 mamp/cm2 in the agar. Results of this study indicate that the protoplasm of paramecia is capable of very fast contraction in response to electric stimulation and that the initial response is always anodal.
Foraminifera in Samples Taken Mainly from Eniwetok Atoll in 1956*
Authors: HIRSHFIELD HENRY I. , CHARMATZ RICHARD , HELSON LAWRENCE
Published: May 2007

SYNOPSIS. The foraminiferal distribution in samples from the Western Pacific collected in the summer of 1956 is presented, particularly those of the islets comprising Eniwetok Atoll. Some information is based upon samples taken shortly after atomic tests had been conducted. The distribution of foraminifera from northern islets where the tests were conducted is compared with that from the southern islets of Eniwetok Atoll. Collections from Eniwetok Atoll are compared with those made the same summer from other locations in the Southern and Western Pacific. A comparison is also made with the survey made by Cushman et al. of the Marshall Islands prior to bomb testing.
Cell‐Free Protein Synthesis by Rumen Protozoa
Authors: CHESTERS J. K.
Published: May 2007

SYNOPSIS. The characteristics of protein synthesis by cell‐free extracts of mixed rumen protozoa have been investigated. ATP,1 GTP, and an energy supply system were necessary for amino acid incorporation which was partially inhibited by cycloheximide but not by chloramphenicol (100 μg/ml). The system was particularly sensitive to the cation concentration of the incubation mixture, maximal incorporation requiring 5 mM Mg++ and 50 mM K+ Incorporation was further stimulated by the addition of 0.25 mM spermidine or 0.25 mM MnCl2. Sucrose gradient centrifugation of the cell sap after amino add incorporation showed that most of the incorporated radioactivity was associated with free polysomes. These polysomes contained 82 S ribosomes which dissociated in high Tris concentrations to yield 40 S and 55 S ribosomes.
Disposition of Prof. R. R. Kudo's Myxosporidan Type Material*
Authors: MEGLITSCH PAUL A. , MEGLITSCH ALISON M.
Published: May 2007

SYNOPSIS. Notification is given of the deposit of paratype material of 36 species of Myxosporida. described by Prof. R. R. Kudo, with the U. S. National Museum.
The Fine Structure of the Flagellum and Kinetoplast‐Chondriome of Trypanosoma (Schizotrypanum) cruzi in Tissue Culture*
Authors: MEYER H.
Published: May 2007

SYNOPSIS. Trypanosoma cruzi in tissue cultures was studied with the electron microscope after double fixation in glutaraldehyde and osmium tetroxide, and embedding in Epon. Previous findings on its fine structure were confirmed, and some new structures were found in the flagellum and kinetoplast‐chondriome.

In the flagellum, an intraflagellar body was found, similar to that observed in other trypanosomes, beginning at the base of the flagellum and running along the axial fibre bundle thruout its length. The axial fibre bundle is formed by interconnecting tubules, the outer ones apparently smooth, the inner ones with a helical substructure. Lateral extensions from the outer tubules in the flagellar bundle seem to enter the intraflagellar body.

The kinetopiast in the leishmania bodies has the same electrondense structure described before. In the trypanosome form it has assumed a large spherical shape, in which the formerly short, compressed fibres have grown in length, are more dispersed and have an irregular shape. They are oriented in the direction of the body's length in parallel array. The whole formation is continuous with a long mitochondrion which begins in the region of the nucleus and extends up almost to the tip of the trypanosome. The matrix of the kinetoplast in these forms is electron‐transparent; the matrix of the mitochondria is rather dense.

In a few extracellular trypanosomes, a special structure was found in which the kinetoplast is composed of electron‐transparent formations, arranged in orderly horizontal lines quite similar to the mitochondrial cristae of the parasite. The significance of this structure is uncertain.
Degradation of Paramylon by Euglena gracilis
Authors: VOGEL KATHRYN , BARBER ALBERT A.
Published: May 2007

SYNOPSIS. Protozoa of the order Euglenida contain a polysaccharide storage product, paramylon, composed of 1, 3‐linked glucose molecules arranged into an extremely resistant granule. An enzyme was purified from the soluble phase of Euglena gracilis which would degrade this polysaccharide to single glucose residues, providing the integrity of the paramylon granule was 1st disrupted by dilute base. This enzyme, a β‐1, 3 glucanase, had optimal activity at pH 5.0 and 60 C and bound tightly to base‐disrupted paramylon substrate tho not to the intact granules. The specific activity of the enzyme was doubled when cell cultures reached stationary phase, the phase where net carbohydrate utilization began. An ATP‐dependent hexokinase reaction was also present in Euglena homogenate. No phosphorylase activity has been found in Euglena. It is suggested, therefore, that Euglena do utilize their paramylon as a carbohydrate reserve and the mechanism of this utilization is by exo‐hydrolytic cleavage to free glucose followed by phosphorylation and glycolysis.
Starvation and Encystment of a Soil Amoeba Hartmannella castellanii*
Authors: GRIFFITHS A. J. , HUGHES D. E.
Published: May 2007

SYNOPSIS. The behavior of the amoeba H. castellanii was investigated in various carbon and nitrogen deficient media with a view to developing a satisfactory replacement medium for the study of encystment and excystment. Media which had been devised for other soil amoebae did not cause H. castellanii to encyst. In these media there was an efflux of material from the cells which was independent of osmolarity but which was minimized by the addition of magnesium. Maximal encystment occurred in a medium containing magnesium chloride alone.

The cysts produced in the magnesium chloride replacement medium are viable and readily excyst when resuspended in the growth medium. The cysts contain cellulose, which is not present in the vegetative amoebae, and differ from the amoebae in their greater resistance to induced lysis and mechanical injury.
Observations on the Life Cycle of Eimeria bilamellata Henry, 1932 in the Uinta Ground Squirrel Spermophilus armatus*
Authors: TODD KENNETH S. , HAMMOND DATUS M. , ANDERSON LARRY C.
Published: May 2007

SYNOPSIS. Oocysts of Eimeria bilamellata were found in Spermophilus armatus, Utah and Wyoming; S. beecheyi, California; and S variegatus, Utah. Oocysts were not found in S. lateralis, S. richardsoni, S. columbianus, S. tridecemlineatus, or the white‐tailed prairie dog, Cynomys leucurus. Experimental infections were established in S. armatus, S. variegatus, and S. lateralis, but not in S. richardsoni, least chipmunks Eutamius minimus, laboratory rats Rattus norvegicus, or Mongolian gerbils Meriones unguiculatus. After one experimental infection S. armatus and S. variegatus were immune to further infections. Spermophilus lateralis could be infected 3 or 4 times before the animals were immune. However, individuals of S. armatus in a natural population had more than one infection with E. bilamellata; probably infections must be of a certain level before immunity develops. When S. armatus were inoculated with about 100,000 oocysts, the animals usually died on the 7th day after incoculation.

Oocysts were 33‐37 by 25‐31 μ (mean 34.5 by 28.2 μ). The oocyst wall was brown and composed of 2 layers. A distinct micropyle was present. Sporocysts were 18‐23 by 9‐12 μ (mean 19.9 by 10.3 μ). In experimental infections, the prepatent period was 10 days and the patent period 5–21 (mean 9) days. Schizonts were 1st seen 7 days after inoculation. They were located above the host cell nuclei of epithelial cells at the tips of the villi of the jejunum and ileum. One or more earlier generations of schizonts were thought to occur, but these were not observed. Gametogony took place in epithelial cells of the jejunum and ileum. Shortly after the merozoites entered the cells, the cells became enlarged and were displaced into the lamina propria. The microgametocytes were considerably larger than the macrogametes and contained a central residual body. Macrogametes had a peripheral eosinophilic layer as well as cytoplasmic granules; both apparently participated in formation of the oocyst wall.
Systematics of Euplotes (Ciliophora, Hypotrichida); Toward Union of the Old and the New
Authors: BORROR ARTHUR C.
Published: May 2007

SYNOPSIS. Prior to the general use of methods revealing the silverline system, members of the genus Euplotes were separated on the basis of body shape, sculpturing and arrangement of cirri. Since 1954, species have been separated on the basis of number of dorsolateral cilium rows, dorsal silverline system, number of fronto‐ventral cirri, and form of the macronucleus. This paper describes E. charon Müller, 1773, E. quinquecarinatus Gelei, 1950, E. alatus Kahl, 1932, and E. bisulcatus Kahl, 1932, 4 species that are difficult to separate solely on the basis of the latter set of characters. By discussion of characters elucidated by a nigrosin‐HgCl2‐formalin method, it is suggested that the following can form a basis for identification of members of this genus: 1) cortical sculpturing, 2) arrangement of all ciliary organelles, including dorsal and endoral cilia, and 3) details of the silverline system. Existing methods are indicated, some far more simple than silver methods, with which these characters can be elucidated.
Effects of Immobilizing Antiserum and Normal Serum on Paramecium Surface Antigen Synthesis
Authors: FINGER IRVING , HELLER CAROL , DILWORTH LINDA
Published: May 2007

SYNOPSIS. Rabbit antiserum can transform paramecia from one scrotype to a 2nd antigenic type. Altho homologous antisera made against antigens sharing the same specificity as that of a treated cell are most effective, other sera lacking crossreacting antibodies also can induce transformation. Furthermore, normal serum from unimmunized animals will often have the same effect. A 0‐40% ammonium sulfate fraction of serum removes a lethal factor, leaving behind an efficient agent for transformation. The activily of this agent will vary from rabbit to rabbit, and apparently is characteristic of a particular rabbit.
Role of Non‐Surface Antigens in Controlling Paramecium Surface Antigen Synthesis*
Authors: FINGER IRVING , ONORATO FRED , HELLER CAROL , DILWORTH LINDA
Published: May 2007

SYNOPSIS. Paramecium aurelia exposed to antisera prepared against cells of a different surface antigenic type are often induced to transform to a new serotype. One possible explanation is that paramecia that are so affected have antigens related to the ciliary antigens, but not accessible to immobilizing antibodies. It is these secondary antigens that are bound by the antibodies, thereby forcing the cells to alter their pattern of antigen synthesis. Examination of affected paramecia has disclosed that secondary antigens are often present but the specificity of these antigens cannot account for the activity of the antisera. It is therefore proposed that antibodies directed against substances other than the immobilization antigens may induce transformation. Two kinds of antiserum, neither of which contains immobilizing antibodies of any sort, are able to markedly alter the expression of the serotypes. One was obtained by immunizing rabbits with culture fluid in which paramecia had been growing. The 2nd was made by injecting rabbits with normal sera from other rabbits.
Eimeria yukonensis n. sp. (Protozoa: Eimeriidae) from the Arctic Ground Squirrel Spermophilus undulatus
Authors: SAMPSON J. ROBERT
Published: May 2007

SYNOPSIS. Eimeria yukonensis sp. n. is described from the Arctic ground squirrel Spermophilus undulatus. The sporulated oocysts are elongate‐ellipsoidal, averaging 24.5 by 13.3 μ. A micropyle is present but an oocyst residuum and polar body are absent. The ovoid sporocysts average 10.9 by 5.9 μ. The sporocyst residuum is ellipsoidal to spheroidal.
Development of Trypanosoma lewisi in Experimental Chimaeras*
Authors: COSGROVE G. E. , LINCICOME D. R. , WARSI A. A.
Published: May 2007

SYNOPSIS. Development of Trypanosoma lewisi in chimaeric mice with and without rat serum supplements was studied in 5 protocols. Chimaeric mice were male and female C3H/An Cum and 1C3F1, [(101/CUM × C3H/An Cum) F1] exposed to 950‐1000 R of whole‐body X‐irradiation. Their hemopoietic systems were replaced with Sprague‐Dawley rat bone marrow.

Trypanosomes did not develop in any mice not supplemented with rat serum. Ih those chimaeric and normal mice given rat serum the trypanosomes grew and developed large populations, more so in chimaeric than in normal animals.

The development of this trypanosome cell in heterologous mice is viewed as mediated principally thru nutritional factors supplied by rat serum with alteration of host‐immune status being of lesser importance.