ALBERT

Notes: Book Reviewed in this article:Resources in America's Future. Patterns of Requirements and Availabilities, 1960–2000. By Hans H. Landsberg, Leonard L. Fischman, and Joseph L. Fisher.Contributions to Urban Sociology, edited by Ernest W. Burgess and Donald J. Bogue.An Anatomy of Kinship: Mathematical Models for Structures of Accumulated Roles, by Harrison C. White.Essays On The Structure of Social Science Models, by Albert Ando, Franklin M. Fisher, and Herbert A. Simon.

Notes: SYNOPSIS. A study of the ectoplasm and infraciliature of Spirostomum ambiguum has been made with light and electron microscopy. Proceeding from the exterior, the cortex is described as the highly structured ectoplasmic portion of Spirostomum consisting of ectoplasmic ridge components and ectoplasmic furrow components. The pellicle invests the ectoplasmic ridges, ectoplasmic furrows, cilia, and adoral membranelles. Electron micrographs show that the cell surface is bounded by two membranes, for the most part parallel. The outer one is continuous with the unit membrane of each cilium; the course of the inner membrane has not been determined in areas bearing cilia.The ridge components are: (i) a collection of fibrils called peripheral ectomyonemes, situated beneath the inner membrane of the cell surface, oriented parallel with the organism's longitudinal axis and following the peripheral contours of each ridge; (ii) distinct rows of tubular fibrils which form a longitudinal bundle called lateral ectomyonemes, situated in the lower portion of each ridge and oriented parallel to its spiral course; (iii) cytoplasmic matrix suspending and surrounding components (i) and (ii). Mitochondria and unidentified electron-opaque oval-shaped or round bodies called X-bodies are dispersed in the ectoplasmic ridges but they also occur in the endoplasm; therefore, they are considered to be transient inclusions instead of constituents of the ridges.The furrow components are: (i) the body cilia and adoral membranelles; (ii) the kinetosomes; (iii) root fibrils, called kinetodesmal strands, of the adoral membranelles; (iv) cytoplasmic matrix suspending and surrounding the furrow components.A trabecular band of randomly oriented filaments, called the endomyoneme is described as possibly the structure called M-band by Randall and Jackson, 1958, and contractile fibrillar system by Yagiu and Shigenaka, 1963.It is suggested that collections of distinct fibrils in Spirostomum be called fibrillar complexes. Acceptance of this suggestion will lead to the designation of four distinct fibrillar complexes in heterotrichs; all four complexes have been described or mentioned in previous studies.Some findings of previous investigators are discussed and confirmed (especially pertaining to Randall and Jackson, also Yagiu and Shigenaka, cited above). Inferences from these independently derived findings are discussed.

Notes: At the age of 50 a Puka-Pukan retires from manual labor and becomes one of the members of The Company, spending hi; evenings shooting popguns or playing checkers, and his nights in ordering the young fry about. He never again has to go fishing, to gather coconuts, or to do any other work.When the malos [young men] bring in their fish they are given to the fathers, who divide them after picking out the choice bits for themselves… To be sure, many of the fathers spend a day or two at fishing now and then, but this is not required of them and they do it only to pass the time… (22).

Notes: 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.

Notes: SYNOPSIS. Studies of certain members of the order Peritrichida, namely species of Carchesium, Epistylis, Vorticella and Zoothamnium, have revealed prominent argentophilic granules, probably cuticular pores, on the bells of all species, located on the transverse striations which encircle the bells. With light microscopy they appear similar to the basal bodies or kinetosomes found in the peristomal regions of the sessile forms, in the posterior ciliary girdles of the telotrochs, and in the scopulas of both sessile and motile organisms. Telotrochs of the various species are depicted with single and multiple rows of the basal bodies from which the membranelles of the locomotor girdles arise.

Notes: SYNOPSIS. A classification of the phylum Protozoa at supra-familial levels is given with definitions or descriptions of all of the involved taxa, some 140 in number. The scheme represents the result of the cooperative efforts of an international group of specialists and consultants who have‘been studying the overall problem for the past several years. Innovations of a nomenclatural nature have been held to a minimum, aside from the use of a system of uniform endings, but several major shifts of taxonomic significance have been introduced at all levels treated, including the subphyla. These revisions are explained in appropriately placed footnotes.

Notes: SYNOPSIS. A comparison has been made of the characteristics of proteins present in two strains of Amoeba proteus, Amoeba discoides, and Chaos chaos. Extractable protein mixtures of each of the strains have been compared with respect to electrophoretic mobilities, enzyme activities, and immunological reactivities. With one slight exception, the three Amoeba strains appear to be identical by all the tests that have been performed but each of the three strains is dearly different from C. chaos by the same tests. The exception may be a difference of a single immunologically active component between A. discoides and one of the A. proteus strains, according to a preliminary observation.

Notes: SYNOPSIS. Active, normal sera or other body fluids from many vertebrate species were found to cytolyze Tritrichomonas augusta; heat inactivated sera agglutinated the organisms. Techniques were devised for quantitative determination of “natural” agglutinating and lytic activity against a number of trichomonads. Amphibian, avian, mammalian, and reptilian sera all possessed activity, as did chicken egg yolk, or yolk sac contents, human ascitic fluid, and cow's milk. For individuals of a given species, levels of “natural” agglutinin did not vary significantly. Among donor species, there were wide and consistent differences. The serum of any one individual, tested against 6 strains of T. augusta, showed constant activity. Agglutinating activity was relatively unaffected by changes of physical factors in the reaction milieu. Lytic activity was restored to heat-inactivated serum by addition of guinea pig serum as a source of complement. When serum was fractionated, agglutinating activity was found primarily in the γ globulins and on into the β. On the basis of these reactions and the activity of specific serum fractions, an antibody mechanism has been postulated.By means of reciprocal agglutination tests with absorbed sera, both “natural” and immune agglutinins have been shown to be specific for Tritrichomonas augusta, T. foetus, and T. suis (?), as well as for Trickomonas gallinarum and Trichomonas vaginalis. Absorption with one species does not remove activity against others. Among strains of T. augusta, absorption with any one removes some antibody against others, but not necessarily all. On the basis of reciprocal absorption and test of 6 strains, 3 antigenic groups have been established: 2 groups are well-separated; the 3rd intermediate between the others and cross-reacting with both.Lack of agglutinin absorption by 2 common enterobacteria, a yeast, and Forssman antigen (sheep erythrocytes) showed that these, at least, were not involved as sources of heterophil stimulation for “natural” antibody. Whether “natural” antibody results from heterophil stimulation, however, or is genetically determined, has not been answered. Direct stimulation of “natural” antibody production by occult infection with trichomonads could not have occurred in the case of trichomonad-free, laboratory reared chicks, or mammalian sera active against T. augusta.

Notes: SYNOPSIS. Two experiments attempted to produce passive immunity against Eimeria bovis coccidiosis in Holstein-Friesian calves. Immune serum concentrated by a freezing technique, or serum globulin obtained by a precipitating technique from immune calves, was injected intravenously or intraperitoneally into young calves. Four calves received concentrated immune serum injected intravenously on the day of oral inoculation with sporulated oocysts and again 7 and 14 days later. Four calves were given intravenous injections with some of the same serum on the 7th and 14th days after inoculation and 4 others were given a single similar injection with the same serum 14 days after inoculation.Three calves in a second experiment received intraperitoneal injections of serum globulins in increasing amounts every 3 days for 2 weeks. The calves were then orally inoculated with sporulated oocysts one week after the last globulin injection. Some calves receiving immune serum had an anaphylactoid reaction characterized by increased respiration rate, dyspnea, coughing, and salivation; however, all affected calves recovered spontaneously within 2 hours. Calves receiving serum globulin had no reactions.Coccidiosis developed in all of the calves in spite of the injection of immune serum or globulin presumed to carry the immune factor. There was no detectable difference in the rate of oocyst discharge or in clinical symptoms between treated and control calves; therefore, no evidence of passive immunity was observed.

Notes: SYNOPSIS. A rapid and sensitive method for determining the nutritional requirements of marine phytoflagellates in axenic culture is described. C14 assimilation (added as NaHC14O3) was used as a measure of response to minimal concentrations of nutrients and for studying the effects of osmotic changes on cells. The results demonstrated that Glenodinium halli Freudenthal & Lee required B12, was stimulated by thiamine, and that it is a euryhaline species. The applications and advantages of this technique in nutritional studies and bioassays are discussed.

Notes: SYNOPSIS. Factors influencing the cultivation of entodinia in vitro have been studied. It was found that removal of particulate material, culture division, or a combination of both resulted in similar maximum protozoal concentrations. At the same time, untreated culture concentrations declined rapidly after reaching a maximum concentration at about the tenth day.At concentrations of streptomycin greater than 25 μg per ml of media, increasing the level of streptomycin extended the time required for a culture to attain a maximum protozoal concentration. A significant relationship (P〉.01) was demonstrated between the starch concentration and the protozoal concentration, and it was found that various combinations of starch and streptomycin produced different relative protozoal concentrations in initial and established cultures. Implications arising from these results are discussed.

Notes: SYNOPSIS. Cultures of Chlamydomonas moewusii begun with log-phase cells of any age had the same lag phases and showed slight but demonstrable synchronous division. Those begun with stationary-phase cells had longer lag phases and showed pronounced synchronously reproductive tendencies. Cultures grown under favorable or unfavorable conditions, and their log-phase cells compared, behaved like log- and stationary-phase cells respectively. Both stationary phase and unfavorably grown cultures shared some of the characteristics of cultures synchronized by light-dark cycling. A light-dark cycled population divides synchronously in direct response to the cycle, and not as a result of being transferred from one medium to another. Synchronous division will occur as 8-fold increases with initial cell densities as low as 10 cells/ml and as high as 100,000 cells/ml. Initial concentrations above 100,000/ml will result in synchronous bursts of less than 8 times the cell number. Cycled cells will continue to divide synchronously when exposed to continuous illumination for an additional 24 hr (i.e., 1 entire “cycle” period). After 12 more hr, they divide exponentially. Continuously illuminated young log cells when subjected to a light-dark regimen begin growing and dividing synchronously by the end of the 1st 12-hr dark period (i.e., during the 2nd 24-hr cycle). The synchronized cell cycle is described cytologkally and quantitatively, and the degree of synchrony for each of the phases of the cell cycle analyzed. After comparing the data from the synchronously and randomly growing cultures, an hypothesis is suggested to explain exponential and synchronous growth and division.

Notes: SYNOPSIS. Evidence is presented for killer and sensitive animals in Paramecium polycaryum. The killer animals excreted in the culture medium a lethal substance which killed the sensitive animals. The lethal substance was unstable at high temperatures and was completely precipitated by centrifugation at 10,000 rpm for 30 minutes. Comparative immunity to killing by killer animals was shown to be possessed by some animals of certain sensitive stocks.Attempts to find a cytoplasmic particle comparable to “kappa” in P. aurelia in killer animals were not successful.

Notes: SYNOPSIS. Sulfate-S35 uptake by intact Euglena cells, as well as incorporation of sulfate-S35 into the insoluble fractions of the cells, was partially inhibited by adding iodoacetamide simultaneously or ten minutes before radioactive sulfate. The identification of S-cysteine acetamide and S-glutathione acetamide showed the presence of glutathione and cysteine in the soluble pool of Euglena but methionine, homocysteine, and S-adenosylmethionine were not found during these experiments. An unidentified radioactive peak was eluted by 2 n HCl during column chromatography of the soluble fraction of Euglena cells. The major compound in this peak was identified as L-cystine on the basis of its infra-red spectrum, paper and column chromatographic characteristics and optical rotation. The use of iodoacetamide permitted the independent demonstration of cysteine and cystine in the soluble pools by eliminating oxidation artifacts.

Notes: SYNOPSIS. Leishmania tarentolae requires at least 10 mμg riboflavin per ml for optimal growth on successive subculture in a denned medium. At this level many organisms are aflagellate or with a short flagellum; higher concentrations of riboflavin did not increase the yield of leptomonads but did increase the proportion with a flagellum at least as long as the body. At limiting levels of riboflavin, acriflavin markedly inhibited growth without producing akinetoplastic forms. With riboflavin at 20 mμ/ml or higher, acriflavin at around 500 mμg/ml permitted an approximately 10-fold multiplication. Seventy % of the leptomonads formed were akinetoplastic and they could not give rise to subcultures.In electron micrographs of acriflavin-treated organisms the nucleus was unaffected but the cytoplasmic organelles, notably the kinetoplast and mitochondria, were altered. The mitochondria appeared swollen with their cristae replaced by circular profiles. In the kinetoplast the dense fibrillar material (probably DNA) lost its structure, became diffuse, and eventually disappeared. The observed changes again indicate close relationship between the kinetoplast and the mitochondria of hemoflagellates.

Notes: 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.

Notes: SYNOPSIS. Mechanically released sporocyts of Eimeria bovis, E. ellipsoidalis and E. auburnensis readily excysted when incubated in a mixture of trypsin, steapsin, and bovine bile. Excystation of intact E. bovis, E. ellipsoidalis and E. auburnensis oocysts occurred after pretreatment at 37°C in aqueous 0.02 M cysteine hydrochloride under an atmosphere of CO2-air or CO2-N2, followed by incubation in an enzyme-bile mixture. Nine % of E. bovis oocysts were activated after 6 hr of incubation at 37 C in a mixture of 0.5% (w/v) trypsin, 0.5% (w/v) steapsin, and 5.0% (v/v) bile at pH 7.5 with 10 hr pretreatment under air and 20% CO2; with 30% CO2, 80% activation occurred; with 50% CO2, 91% of the oocysts were activated. At CO2 levels from 10 to 40%, pretreatment with CO2 and N2 yielded less activation than CO2 and air. Pretreatment with CO2-N2 (50–50) for 2 hr resulted in 37% activation; for 6 hr, 60%; for 10 hr, 94%; and for 14 hr, 99%. After pretreatment under 50% CO2 for 10 hr, 95% excystation was obtained by incubation for 6 hr in 0.5% trypsin and 5.0% bile. Only 76 or 69% excystation occurred when 0.25% trypsin or 1.0% bile, respectively, was substituted. Addition of steapsin to this mixture caused little change in the results. In oocysts pretreated 14 to 21 hr with steapsin, 2% or less excystation occurred after 6 hr in a trysinbile or bile mixture. E. ellipsoidalis oocysts, pretreated for 10 hr under CO2-N2 (50–50), underwent 61 and 80% excystation when incubated for 2 and 6 hr, respectively, in trypsin, steapsin, and bile. E. bovis oocysts enclosed in a dialysis bag inside an intestinal fistula became thinned or flattened at the micropyle after 24 hr, and excystation occurred when these oocysts were mixed with trypsin, steapsin, and bile and returned to the fistula for 4 hr. No excystation occurred when oocysts without added enzymes were left 48 hr in the fistula. Sporozoites escaped first from sporocysts and then from oocysts.

Notes: SYNOPSIS. A study, based on tissue and blood smears, has been made of the incidence and intensity of Leucocytozoon in 193 yellow-billed magpies. Tissue smears had a significantly higher gametocyte frequency, as well as a higher density level than was found in the blood films. Three hundred and seven adult magpies were examined for relationship of season to blood-parasite incidence. Both incidence and intensity, as indicated by blood smears increased during the spring months; the peak occurred in March; the lowest findings were in August and September. Data from tissue smears indicate a high incidence throughout the year.

Notes: SYNOPSIS. An occurrence of the allogromid genus Shepheardella is here reported for the first time from the western hemisphere. The foraminifer is briefly redescribed and illustrated.

Notes: SYNOPSIS. A comparison of the effects upon trypsin-dispersed chick liver cell cultures of a virulent (Jones' Barn) and a non-pathogenic (Lahore) strain of Trichomonas gallinae revealed significant differences in behavior of the parasites in cell cultures and in the response of such cultures. The virulent strain multiplies faster in nutrient medium in the presence of cell cultures; stimulates great activity of the macrophages; is not handled effectively by these phagocytes in which it can multiply causing their ultimate destruction; is found significantly more often within the cytoplasm of the liver epithelial and fibroblast-like cells; causes very much more profound degenerative changes in all the cells, both invaded and non-invaded; and suppresses effectively the division rate of the fibroblast-like cells. On the other hand, the nonpathogenic strain multiplies at a lower rate in the presence of cell cultures; stimulates less activity of the macrophages; is handled readily by these phagocytes in which it multiplies only very rarely, if ever; is found seldom within the liver epithelial and fibroblast-like cells; causes far less degeneration of all the cell culture elements; and suppresses significantly less the dlvision rate of the fibroblast-like cells.At the end of a 20–24 hour period typically only a few living cells are left in cultures exposed even to attenuated isolates of the virulent strain, whereas those inoculated with the mild one do not show much degeneration even after 28 hours. The effects upon the cell cultures of cell-free filtrates of actively growing trichomonad cultures are relatively minor, but the changes caused by the filtrates of cultures of Jones' Barn strain appear to be more extensive than those caused by similar filtrates of Lahore strain.

Notes: SYNOPSIS. An iron deficiency was noted for Tetrahymena grown in a proteose-peptone-yeast extract medium. Thus, the addition of an iron chelate and glucose was found to give consistent and luxuriant growth, whereas a number of other additives, including sodium acetate, an inorganic salt mixture lacking iron, and vitamins were found to be without influence on growth rate or cellular yield.Iron-deficient cells showed a marked reduction of oxidative capacity when suspended in a non-nutrient medium as well as when supplied with oxidizable substrates. A 1 hour incubation of iron-deficient Tetrahymena with iron chelate restored oxidative capacity only when the cells were suspended in a nutrient (peptone) medium. Growth of Tetrahymena in media autoclaved with salts resulted in cells with a larger volume but with no increase in oxidative capacity.The addition of 2,4-dinitrophenol elevated respiration of cells suspended in a non-nutrient medium, and of iron deficient cells suspended in the growth medium, suggesting that this compound increases the availability of iron or iron containing compounds, or by-passes the limiting steps.Respiratory quotients were lowered by an iron deficiency and elevated when the cells were grown in the presence of iron and glucose. This suggests more complete utilization of the carbohydrate, possibly due to the activity of a number of enzymes known to be iron-containing metalloproteins that are required for oxidative glucose dissimilation.

Notes: SYNOPSIS. Small amebas are difficult to describe because of the lack of permanent morphological criteria. Investigations from the nuclear division and physiological points of view may be useful, but the study of motion and behaviour under natural conditions gives better results in order to show the natural relationship. Descriptions of four new forms of small marine amebas are given. These species belong to the genera Rugipes, Acanthamoeba, Flabellula and Vahlkampfia.

Notes: SYNOPSIS. Colonies of Bufo bufo kept for pregnancy diagnostic purposes were found infected with a new species of microsporidian, Plistophora myotrophica, causing atrophy of the striated muscles. Lysis of myofibrils by the parasite leads to the formation of fusiform spaces in the fibers packed with microsporidian spores. A cyst wall is not formed. Toads become emaciated and suffer heavy mortality.In experimental infections the sporoplasm hatches in the gut. Fusiform granular bodies, not identifiable as blood cells, are found in the muscle capillaries at 18 days and possibly represent early stages of the parasite. Between 18 and 23 days division of the parasite occurs in the muscle fibers, first by binary fission, then multiple fission and finally by plasmotomy culminating in the formation of sporonts with 16 to 100 nuclei. Separation into sporoblasts precedes spore formation.In old infections phagocytes, which are probably monocytes, infiltrate between the groups of spores and ingest them. Ingested spores which stain differently from their free counterparts, are dead. Muscle regeneration is initiated by the toad, with the formation of long chains of sarcoblasts, sometimes 30 or more in a chain, responsible for the regeneration and redifferentiation of myofibrils.Tadpoles are refractory to infection. As toads normally lead a solitary life the high local incidence in the area from which the toads were collected is explained only if the toads acquire the infection from spore-contaminated ground in the breeding season.

Notes: SYNOPSIS. Developing and mature sporangia of the true slime mold Didymium nigripes were studied with the electron microscope to follow the course of spore formation. The sporangium forms from the plasmodium as a protoplasmic bleb which differentiates into a stalk and an apical sphere containing a mass of protoplasm. Nuclei within this protoplasmic mass undergo synchronous division (presumably meiosis). The division spindle forms within the nuclear membrane which is retained intact throughout the division; centrioles have not been observed at the spindle poles. At the same time the nuclei are dividing, the protoplasm cleaves to give ultimately uninucleate spheres—the incipient spores. Capillitial threads come to lie in the furrows created by the cleaving protoplasm. A wall consisting of an inner thick component and an outer thin component forms about each sphere. Cyto-chemical tests suggest that the inner wall of the spore is cellulose-containing and that the outer component might contain chitin.

Notes: SYNOPSIS. Previous attempts to dismember the genus Trypanosoma, by creating additional genera or subdividing it into subgenera, failed to gain acceptance, but, in the case of mammalian trypanosomes, the arrangement of species into informal groupings found more general recognition. However, as subordinate groups tend to multiply with advances in our knowledge, the classification of these trypanosomes threatens to become too unwieldy. It is therefore proposed to give assemblages of allied species a formal taxonomic status, by subdividing the genus Trypanosoma into subgenera, corresponding to previous minor groupings, but retaining the two major sections. The subgenera and their type-species are as follows:A. Section STERCORARIA, with 4 subgenera:1. Megatrypanum subgen.n.: Trypanosoma (Megatrypanum) theileri; 2. Herpetosoma Doflein: Trypanosoma (Herpetosoma) lewisi; 3. Schizotrypanum Chagas: Trypanosoma (Schizotrypanum) cruzi; 4. Endotrypanum Mesnil & Brimont: Trypanosoma (Endotrypanum) schaudinni.B. Section SALIVARIA, with 4 subgenera:5. Duttonella Chalmers: Trypanosoma (Duttonella) vivax;6. Nannomonas subgen.n.: Trypanosoma (Nannomonas) congolense; 7. Pycnomonas subgen.n.: Trypanosoma (Pycnomonas) suis; 8. Trypanozoon Lühe: Trypanosoma (Trypanozoon) brucei.

Notes: SYNOPSIS. An electron microscope study of Leishmania donovani revealed major differences between the intracellular leishmanial and the extracellular leptomonad stages. Parasites were also removed from infected hamster spleen, inoculated into cultures, and examined at intervals during incubation in order to follow changes during the transformation from one stage to the other. Prominent changes are evident primarily in the kinetoplast and the nucleoli after several hours of cultivation when the parasite is in an intermediate stage of transition. The kinetoplast, a composite organelk containing DNA and cristae mitochondriales, is a regular, sausage-like structure in the leishmanial stage, but becomes irregular and enlarges extensively after a few hours in vitro, developing branches that are mitochondrial in nature and which, very likely, become new mitochondria. In the nucleus, significant nucleolar changes occur. The two homogeneous nucleoli characteristic of the leishmanial stage merge during transformation into one which is larger, less compact, and composed of small centrally located granules about 100 Å in diameter and larger particles over 200 Å in diameter at the periphery. These transformations of the kinetoplast and nucleolus are undoubtedly expressions of adaptive changes in the metabolic pattern of an intracellular parasite transferred to a markedly different extracellular environment of much lower temperature.It was also found that the leishmanial stage of the parasite has two unit membranes which extend over the flagellum and the flagellar pocket; the intermediate stage and the leptomonad have only a single membrane. Furthermore, some leishmanias in spleen cells were found to be covered by a capsule-like structure formed by the deposition of fine granular material between the two unit membranes. Since two to four organisms were occasionally found within such capsules, it is possible that encapsulation is a preparatory step for reproduction.

Notes: SYNOPSIS. Hypophrya fasciculata gen. nov., sp. nov., a mesosaprobic epibiotic suctorian ciliate, was collected from stagnant water in Chapultepec Park, Mexico, D.F., on Epistylis plicatilis, in turn epibiotic on the molluscans Limnaea attenuata and Physa osculans. The zooids (average size, 118 × 78 μ) have fasciculate tentacles distributed on the apical and proximal regions, and the stalks are ca. 248 μ in length. Feeding and internal budding were observed.

Notes: SYNOPSIS. Temperature-cycling of the type used with T. pyriformis was applied to cultures of Tetrahymena vorax Tur in attempts to induce synchronous cell division. The best temperature-cycling treatment found produced division indexes of 40% (T. pyriformis yields 85%). The age-dependent thermal sensitivity of untreated T. pyriformis which is often cited as an explanation for its response to temperature-cycling has been demonstrated in T. vorax. However, a difference was noted which may explain the different degrees of synchrony obtained. It is suggested that the fission-delay distributions obtained with T. pyriformis can be explained on the basis of an hypothesis in which all cells behave uniformly. In T. vorax, in contrast, the delay distributions suggest that the thermal sensitivity pattern is not the same in all cells.

Notes: SYNOPSIS. Precystic organisms embedded in agar become abnormal cysts. Some of them are excystable rod-like or ellipsoid forms and the others, non-excystable fiat ones. Major axis of the rod-like or ellipsoid cysts is parallel with the body axis of the previous precystic organisms, because when the cysts are formed the protoplast within the secreted cyst walls rotates or agitates slightly around the major axis but movement around the minor axis is precluded.The fibrillar structures appearing in excystment from abnormal cysts are bilaterally symmetrical, different from the normal spherical cysts showing radial symmetry. The two poles from which the fibrils radiate are situated opposite each other but not at the extremities of the cyst. The locus of the anterior pole corresponds to the site of oral primordia in dividers and reorganizers.When the anterior part of the original adoral membranelles (AZM) in the early precystic animals is removed, the ellipsoid cysts from the abbreviated animals show a disturbance of the anterior fibrillar arrangement. The primoidium of the future AZM runs straight from the anterior extremity of the cyst toward the uninjured posterior pole. Ellipsoid cysts from precystic animals after the posterior region is removed similarly have disturbed fibrils near the posterior extremity of the cyst. The AZM primordium then arising on excystment extends from the uninjured anterior pole toward the damaged posterior extremity of the cyst. Similar events are found also in spherical cysts from anterior and posterior fragments of precystic animals.In either case, though the initial phase of the AZM primordium shows irregular contour, leaf-like shape is accomplished later accompanying the increase of primordial granules, while the other ciliary primordia such as undulating membrane and cirri arise at their corresponding areas. All can produce normal excysted animals.The ciliary primordia appearing upon excystment, notably that of the AZM, therefore seem to have descended from the precystic stage or foregoing trophic one.

Notes: SYNOPSIS. In a survey of the coccidia of prairie dogs in northern Colorado, Eimeria ludoviciani sp. n. was found in 45, Eimeria larimerensis sp. n. in 3, and Eimeria cynomysis Andrews, 1928 in 1 of 86 black-tailed prairie dogs, Cynomys ludovicianus ludovicianus.

Notes: SYNOPSIS. Acanthamoeba sp. Neff can synthesize 4 of the 10 essential amino acids, namely, histidine, lysine, threonine and tryptophan. However, in this minimal medium, the non-essential amino acid glycine was also required for growth. Serine or threonine could replace glycine, but the growth rate was reduced.

Notes: SYNOPSIS. The body surface, sucking disc and median bodies of Lamblia duodenalis have been studied on ultrathin sections in the electron microscope. The body is covered by a pellicle, displaying a striated structure in the area of the sucking disc. The striation is due to 150 Å thick dense ridges which are spaced in distances of 200–400 Å. The ridges are formed by the internal pellicular membrane and have a triangular cross section with a very dense apex. They are arranged concentrically and run parallel to the surface of the sucking disc lobes. Anteriad to the nuclei in the median line a space is free of ridges. The margin of the sucker is elevated above the body forming a sharp crest of the ridged pellicle.This crest is the inner wall of a marginal groove delimiting the sucker from the body. The outer margin is circumscribed by a fold in the body tapering to the posterior end. A ventral groove containing the two ventral flagella lies in the median line. The movement of the ventral flagella pushes the medium through the marginal and ventral grooves thus producing vacuum in the sucker area.The median bodies are composed of numerous 150 Å thick tubular fibrils. They differ in their ultrastructure from the parabasal apparatus in other flagellates and have nothing in common with the kinetoplasts. Their functional significance awaits elucidation.

Notes: SYNOPSIS. Glossina palpalis R-D 1830 and G. pallicera Bigot 1891 in northwest Liberia were found to be infected with a flagellate parasite which never invaded the mouthparts. The parasite occurred as a number of distinctive crithidial and trypanosomal forms, and although infection was commonly confined to the midgut, it occasionally extended into the hind-gut; infections of the hindgut only were rare. The parasites also infected the coelomic cavity of the host. Attempts to produce further developmental stages in N.N.N. medium, rat, crocodile, varanid and hen failed. There are morphological similarities between the parasite and some developmental stages of Trypanosoma grayi Novy 1906, but reasons are advanced why the two forms do not belong to the same, but possibly to closely related species.

Notes: SYNOPSIS. Paramecium caudatum was cultivated in a medium containing 17 amino acids, nucleic acid components, fatty acids, a supplementary carbon source, B-vitamins and stigmasterol. Growth was enhanced when particles such as corn starch, rice starch or activated charcoal were added to the denned portion of the medium along with an unidentified protein factor found in either yeast or peas. The addition of a synthetic magnesium silicate to the chemically known constituents eliminated the apparent requirement for the protein factor. Since the continuous maintenance of P. caudatum in a medium of known chemical composition is now possible, metabolic studies can be carried on with greater facility.

Notes: SYNOPSIS. Glucose-6-phosphate and adenosine triphospbate levels in glucose-abundant and glucose-depleted preparations of the culture forms of Schizotrypanum cruzi were measured. Glucose-6-phosphatc formation was dependent upon an exogenous source of glucose. Adenosine triphosphate levels were maintained whether exogenous glucose was present or absent. Net synthesis of adenosine triphosphate in the presence of exogenous glucose was observed. The results favor the presence of a hexokinase in S. cruzi.

Notes: SYNOPSIS. A modification of the method of Marmur permits the ready isolation of native deoxyribonucleic acid (DNA) from some strains of Trichomonas vagtnalis and T. gallinae. Analysis of the purified DNA by thermal denaturation and density gradient centrifugation shows both to be quite rich in adenine plus thymine and to display considerable compositional heterogeneity. Analyses for dry weight, total nitrogen, and amounts of the nucleic acids are also given.

Notes: SYNOPSIS. Three acidophilous volvocine flagellates from peat water in Czechoslovakia were obtained in pure culture by the washing technique. Two of these, Carteria acidicola and Chlamydomonas acidophila, grew so densely in low-pH Euglena gracilis media containing glutamic acid as to suggest they possess a vigorous heterotrophy. The other, Carteria turjosa, grew less well and required vitamin B12. In peat-water media the upper limit of growth was 5.5. The lowest pH tested, 2.5, permitted growth of Carteria acidicola and Chlamydomonas acidophila. Some peptone media permitted growth at pH 6.0. The morphology of these flagellates is described.

Notes: SYNOPSIS. Mastigonemes occur on flagella of many species of Protozoa, but the only function so far proposed for the mastigonemes is to increase the effective surface of the flagellum. Locomotion of Ochromonas malhamensis, O. danica, and an unidentified marine chrysomonad was examined by means of high speed microcinematography up to 600 pictures per second. In addition, analyses were performed on the movement of the organism in a suspension of polystyrene spheres (1.17 μ in diameter). The films clearly show that the organisms move by means of a planar sine wave in the long anteriorly-directed flagellum. The wave starts at the basal end of the flagellum and progresses distally. It is apparent that the organisms are pulled forward by the action of the long flagellum, and that the flagellum does not push backward as would ordinarily be expected with a forwardly-directed sine wave.It is well known that flagellar sine waves usually start at the base, move distally, and produce a push toward the point of attachment. It also is known (2) that in Mastigamoeba a helical wave may start at the tip, progress proximally toward the base, and pull the organism. However, in the present organisms the wave begins at the base, moves distally (i.e., forward), and pulls the organism. The flagellum is a true tractellum. The theoretical calculations of Taylor (1952, Proc. Roy. Soc., 214A, 158) show that if a thin cylinder, undergoing sinuous movements produced by a traveling sine wave of active bending, has a roughness of surface which is sufficiently great and has a certain directional character, propulsion may be achieved in the direction opposite to that expected of a smooth cylinder bending in exactly the same manner. It is known that the long flagellum of the chrysomonads is pantonematic, i.e., has numerous stiff lateral mastigonemes on at least two and probably all sides. It is proposed that one function of these mastigonemes is to provide a roughness of surface which brings about this type of reversal.

Notes: SYNOPSIS. During conjugation of E. woodruffi, the micro-nucleus divides repeatedly four times prior to synkaryon formation and twice thereafter. The first division resembles an ordinary somatic mitosis, resulting in the formation of two daughter nuclei in each conjugant. Both products of this division enter the second division which corresponds to the heterotypic division of other ciliates, characterized by a parachute stage. Following this stage sixteen bivalents appear and separate into dyads and pass to the poles. During the following divisions individualized chromosomes do not appear but only certain chromatin elements comparable to those seen in the somatic and preliminary divisions. These divide and pass to the poles. All daughter nuclei of the second division enter and complete the third division. Only two of the products of the third division enter the final pregamic division while the rest degenerate. Exchange of pronuclei and their fusion leads to synkaryon formation. The conjugants then separate and in each exconjugant the synkaryon divides twice in rapid succession. Of the four products one condenses to become the functional micronucleus, another enlarges rapidly to become the macronuclear anlage while the remaining two degenerate and disintegrate. The old macronucleus breaks into irregular and polymorphic bodies. As the macronuclear anlage enlarges the remnants of the old macronucleus reorganize and fuse with the macronuclear anlage to form a characteristic vegetative macronucleus.

Notes: SYNOPSIS. Four new species of Myxosporidia have been described from Ophicephalus punctatus, a fresh water fish of North India: Myxobolus aligarhensis n. sp., M. ophicephali n. sp., Unicauda basiri n. sp., and Henneguya zahoori n. sp. Observations have been made on some stages of their life-cycle other than the spores.

Notes: SYNOPSIS. Tetrahymena pyriformis W, transferred from proteose peptone to bacterized Cerophyl, exhibited the same growth rate whether A. aerogenes, E. coli, or S. marcescens was the food organism. When T. pyriformis was suspended in sterile Cerophyl and fed various amounts of killed bacteria, the initial growth rate was the same as when viable bacteria were used, and the total increase in ciliate population was a function of the amount of bacterial protoplasm added. With Cerophyl concentrations below 0.1%, ingestion of the bacteria and reproduction of the ciliates were greatly reduced, suggesting a phagotrophy-inducing factor in the Cerophyl. T. pyriformis resuspended in sterile Cerophyl can be fed washed killed bacteria for studies on various aspects of the metabolism of phagotrophic ciliates.

Notes: SYNOPSIS. N. gigas Balech, 1941, has been found again in Uganda and cultured in the laboratory. Some features of its morphology and behavior were studied. The buccal cavity has a small pit. Trichocysts are found in the endoplasm as well as the cortex. The ciliate appears to be highly sensitive to light. Cyclops was an important predator. The size of N. gigas is very variable.

Notes: SYNOPSIS. A comparative morphological study was made of 73 clones of Eudorina isoated from 44 natural populations and grown under controlled environmental conditions. Utilizing the information obtained in this study in association with the existing taxonomic and experimental literature concerning Eudorina a monographic treatment of the genus was prepared. Nine species and 4 varieties are now recognized.Sexual compatibility was investigated with 22 heterothallic pairs, 3 male strains and one female strain representing 4 species and one variety of Eudorina. Five partially or completely sexually-isolated groups were found: 3 groups containing strains of a single species, a fourth group composed of strains of another species, and a fifth group made up of strains of 3 different species. Strains with different zygote arrangements were found generally not to intercross.Intraspecific crosses indicated that a single pair of alleles controls the inheritance of mating types and that gene flow occurs between strains representing different natural populations. Interspecific crosses resulted in the formation of polyploid or aneuploid F1 offspring which shewed an abnormal segregation of the mating types. Abnormal mating type segregation was also obtained in F2 crosses involving certain of the hybrid polyploid offspring.

Notes: SYNOPSIS. A new family (Pseudocohnilembidae) of hymenostome ciliates is described based primarily upon the pattern of the buccal infraciliature which consists of two parallel rows of kinetosomes, nearly equal in length, representing the bases of two large membranes, and of argentophilic fibrils arranged in a more or less uniform design in the buccal cavity. A new genus (Pseudocohnilembus) with three species (one from Great Salt Lake, Utah, and two from the Atlantic coast) is described. These organisms bear superficial resemblance to Cohnilembus; an analysis of the buccal infraciliature of Pseudocohnilembus is presented, including a discussion of and comparison with that of Cohnilembus.

Notes: SYNOPSIS. Miamiensis avidus n. g., n. sp., a marine facultative parasite, is described. Morphological studies were made on specimens treated with the Chatton-Lwoff silver impregnation technique and living material was examined with phase microscopy. Particular attention was given the infraciliature of the buccal apparatus and its importance to generic assignment in the order Hymenostomatida.

Notes: SYNOPSIS. Morphogenesis in the small holotrich ciliate Pseudocohnilembus persalinus has been found to be more complex than that reported to date for any other hymenostome species, at least with respect to the major phenomenon of stomatogenesis. Formation of two anlagen or fields of proliferating kinetosomes in the vicinity of the old oral area initiates the highly autonomous process. Subsequently a number of separate but coordinated morphogenetic movements occur which involve not only the new anlagen and their extraordinary growth and fragmentation but also the bases of the “old” ciliary buccal organelles.Particularly indispensable in our investigation was the Bodian protargol technique which reveals the external ciliature of a properly fixed organism as well as components of its infraciliature. The Chatton-Lwoff silver impregnation method, however, was also very useful in the overall comparative study of the present and related species of ciliates.At one stage in stomatogenesis of Pseudocohnilembus persalinus there is clear evidence of a basic tetrahymenal plan of organization of the buccal ciliature, even though this is not at all apparent in the mature, non-dividing ciliate. Such a revelation underlines the significant value of morphogenetic studies in comparative ciliate systematics, for our findings permit retention of the genus Pseudocohnilembus in the suborder Tetrahymenina of the holotrich order Hymenostomatida. At the same time, however, they necessitate revision of some currently held concepts in the fields of ciliate morphology, taxonomy, and phylogeny.

Notes: SYNOPSIS. Sporocysts of the trematode Bucephalus cuculus McCrady in Maryland oysters, Crassostrea virginica (Gmelin), have been sometimes found to harbor a microsporidian parasite considered to be a new species of Nosema. The ovoid spores are about 3 by 2 ü in sectioned material. The spore membrane has a PAS positive mass at the anterior end. The polar filament extends inwardly from this end and coils within a posterior “vacuole.” An anterior “vacuole,” containing no visible structure besides the basal portion of the filament, is also present. The sporoplasm forms a girdle near the middle of the spore. It contains a tiny elongated chromatin mass believed to consist of two nuclei in close proximity.

Notes: SYNOPSIS. Respiration of nonphotosynthetic Euglena gracilis var. bacillaris is maximally stimulated by 10–30 on ethanol; lower ethanol concentrations produce lesser stimulation. The rate of respiration on ethanol is independent of pH (pH 3.0–9.0). Acetate-grown and ethanol-grown cells are similar in these respects. The respiratory quotient of ethanol metabolism is 0.30, and 0.966 mole O2 is consumed per mole of ethanol utilized. Constancy of the respiratory quotient and O2: ethanol ratio with time indicates that there is no transitory accumulation of partially oxidized intermediates during ethanol metabolism. A variety of tests indicate that oxidation of intracellular reserves continues during ethanol metabolism.

Notes: SYNOPSIS. It has been shown that larva-to-larva transmission effected by means of free-living Crithidia can account for the incidence of this flagellate in natural populations of adult mosquitoes. Larval infections lost at molting were reacquired early in subsequent instars. Infections of pupae came about by contamination of the midgut of the prepupa with nectomonads while the peritrophic membrane was being shed prior to pupation. By the time pupation was completed the flagellates had become immotile and continued to multiply in the pupal midgut; they again became motile in the midgut of the newly emerged adult. Adult-to-larva transmission was effected through water contaminated by adult mosquitoes infected with flagellates.

Notes: 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.

Notes: SYNOPSIS. From a total of 223 diverse habitats located in Australia, New Zealand, Fiji, Hawaii, Japan, Hong Kong, and the Philippines, 144 yielded Tetrahymena pyriformis. These collections were taken from a latitude of 35° N. to 35° S., from sea level to 4500 feet, and temperatures ranging from 15° to 30°C. From these habitats 2300 clones were isolated, of which approximately 800 were examined for micronuclei and 450 tested for mating type.Two distinct interbreeding populations were isolated from the Australian collections. They failed to mate with any of the 10 known varieties and are therefore designated as varieties 11 and 12. No sexually active clones were found in New Zealand, Japan or Hong Kong. However, clones belonging to variety 9, previously found only in Colombia and Panama, were isolated from habitats in Hawaii and Fiji. This evidence suggests that possibly variety 9 is confined primarily to the tropics. There seems to be no other correlation of varieties with land mass.Representative clones from each habitat were established in axenic culture, all of which grew well in proteose-peptone. When first tested, a number of mutants were found among the 66 clones screened for their nutritional requirements. Some grew without thioctic acid or niacin. Several required aspaitic acid and one required biotin and proline in addition to the 18 nutrilites required for strain E. No pattern could be found which related the mutants to a particular region. Examination of the mutants one year later revealed that the synthetic capacity for both niacin and thioctic acid had been lost and that those clones requiring aspartic acid had acquired the capacity to make the amino acid.

Notes: SYNOPSIS. An electron-microscope study of the macronucleus and the micronucleus of Blepharisma intermedium Bhandary has been made. Sections show that the macronucleus is bounded by a double membrane. Inside, there are two types of bodies: (a) small irregular bodies, from 0.05 to 0.2 μ in diameter, and (b) larger bodies, from 0.4 to 0.6 μ in diameter. The former are intrepreted as cut ends of long, branching filaments traversing the nuclear cavity in all directions. They correspond to the DNA filaments obtained by centrifugation and KCN action on the macronucleus. Each filament is made of fibrils aboue 150 Å thick. The large bodies correspond to the nucleoli; they also show a fibrillar structure. They offer the added interest of displaying dense particles, from 100 to 800 Å in size, whose nature and significance are obscure. The micro-nucleus has a double membrane, and the contents are divisible into an electron-dense network and a material of low density which fills the interstices of the network.

Notes: SYNOPSIS. Erythrocyte-free Plasmodium lophurae were lysed by freeze-thawing and the lysate subjected to contrifugation. Two fractions were obtained: (1) hemozoin, an insoluble protein-containing pigment and (2) soluble proteins. Hemozoin when “solubilized” in 4 M urea was immobile upon electro-phoresis in a 4 M urea starch gel. The soluble plasmodial proteins were grossly contaminated by host cell hemoglobin, but were readily separated from the latter by starch gel electrophoresis. Employment of the Ouchterlony and immunoelectrophoretic techniques demonstrated that one of the major antigenic components in this avian plasmodium is hemoglobin. The malarial pigment showed no antigenicity. Rabbit antisera prepared against formalinized erythrocyte-free parasites discerned some 4 to 6 precipitating antigens, but no such reaction was obtained using hyperimmune chicken serum after naturally induced blood infections. These studies show the distinct nature of the host and parasite by physico-chemical means and illustrate the value of the immunoelectrophoretic method in providing a simple and sensitive tool for detecting impurities in parasite protein preparations. It is further suggested that confusion in host and parasite antigens as described in the literature may in part be due to these unidentified erythrocyte elements.

Notes: SYNOPSIS. Cultivation of the mammalian trypanosomes can be accomplished in the following artificial environments: monophasic and diphasic blood agar, dialysate, undefined, and partially defined liquid media, semisolid media, avian embryos, and tissue cultures. The experimental purpose for cultivating a species usually determines the type of medium used. The various media are considered with reference to problems concerned with diagnosis, serology and morphology as well as metabolic, biochemical studies, etc., for which the different types have been utilized. Nutritional and environmental requirements for in vitro growth are noted. Most mammalian trypanosomes, regardless of the medium, multiply in stages peculiar to the invertebrate host. In certain species these forms are infective, in others they are not. In only a few instances has there been development beyond the usual invertebrate forms to an infective form or of the adult trypanosome of the vertebrate. Considerable progress has been made toward attaining a defined medium, but the exact nutritional components as yet have not been determined.Development of chemically defined media and of media which will support the growth of trypanosome stages which thus far have not been cultivated in vitro are major problems for the future.

Notes: SYNOPSIS. Urceolaria spinicola n. sp. is described from the sea urchin Strongylocentrotus droebachiensis at Mt. Desert Island, Maine. In the summer of 1963, it was found in abundance on the host, especially on the short spines and pedicellariae of the circumoral region and on those surrounding the periproct. It is a harmless bacterial feeder. Characteristic features are its low cylindrical form and H-shaped macro-nucleus, and the presence of about 25 relatively long cirri on the margin of the adhesive disc.

Notes: SYNOPSIS. Twenty strains of hartmannellid amoebae have been studied. All the strains grew axenically in liquid and chemically defined media. Strains were found to differ their rate of growth, optimum temperature for growth and in amino acid requirements. All except one strain (Lilly) were found to be serologically related by the immobilization test. Direct observation of the trophozoites and cysts, and the results of serological and physiological tests, have led to the conclusion that the 20 strains should comprise a single species until further information is gained on these and other representatives of the genus.Earlier literature on the classification of hartmannellid amoebae has been critically reviewed, and it is concluded that Hartmannella castellanii Douglas 1930 is the correct name for the species. It is suggested that Acanthamoeba castellanii (Volkonsky 1931), Hartmannella glebae (Dobell 1914) and H. rhysodes Singh 1952 became synonyms of H. castellanii, and that Mayorella palestinensis Reich 1933 be transferred to the genus Hartmannella.Some strains of H. castellanii were able to grow at mammalian body temperature. Since the species appears to be common and widely distributed, and farms cysts which resist desiccation, it is probable that the occurrence of amoebae in mammalian cell cultures has arisen by contamination from the air.

Notes: SYNOPSIS. The effect of trypsin on the pellicle of Euglena gracilis has been studied. A simple apparatus which permits the incubation of a number of culture flasks under identical conditions of illumination is described. Cells of E. gracilis suspended in 0.01 M NH4HCO3 are rapidly lysed by trypsin. Lysis is prevented by 0.3 M sucrose, 0.3 M glucose, 0.3 M glycerol, 0.15 M KBr or 0.15 M NaCl. After treatment with trypsin in the presence of a protective solute the cells are still osmotically stable when resuspended in distilled water, indicating that free protoplasts are not liberated. These solutes do not protect isolated, empty pellicles against the action of trypsin. It is suggested that cells of E. gracilis are only susceptible to trypsin when they are swollen as a result of exposure to hypotonic media: that the resultant stretching of the pellicle permits lysis by allowing the enzyme to penetrate to sites which are normally hidden.

Notes: 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.

Notes: SYNOPSIS. Two new species of Isospora are described from the feces of an eastern spotted skunk Spilogale putorius ambarvalis imported into Montana from Florida. The oocysts of I. spilogales n. sp. are 29 to 38 by 22 to 28 μ and contain 2 sporocysts measuring 17 to 22 by 13 to 16 μ; a few Caryospora-like oocysts containing a single sporocyst were considered abnormal I. spilogales oocysts. The oocysts of I. sengeri n. sp. are 16 to 23 by 12 to 18 μ and contain 2 sporocysts measuring 10 to 14 by 8 to 12 μ.

Notes: SYNOPSIS. The Tulahuen and Peruvian strains of Trypanosoma cruzi have been compared as to their ability to metabolize C14-glucose uniformly labeled, or labeled in carbons 1, 2, or 6. Most of the radioactivity from uniformly labeled glucose is incorporated into organic acids in both strains, but significant radioactivity is also recovered in CO2. The Tulahuen strain has a slightly higher rate of glucose consumption, and the rate of incorporation of uniformly labeled glucose-C14 into CO2 is also higher. More radioactivity is incorporated into proteins from uniformly labeled glucose-C14 in the Tulahuen strain, but the radioactivity recovered in total organic acids is fairly similar in both cases. On the basis of the rates of C14O2 production from C14-glucose specifically labeled in carbons 1, 2, or 6, as well as the rates of incorporation into glycerol from uniformly labeled C14-glucose and glucose-6-C14, it is considered that the reactions of the pentose phosphate pathway play a more important role in the Tulahuen strain. The pentose phosphate pathway accounts for 41.4% of the glucose catabolized by the Tulahuen strain compared to only 27.9% in the Peruvian strain. It is suggested that differences in the participation of alternative pathways of carbohydrate metabolism may have some relationship to pathogenicity.

Notes: SYNOPSIS. Dactylosoma is a genus of blood protozoa which undergo schizogony, without producing pigment, in the red cells of the lower vertebrates, especially amphibia. The best known species is D. ranarum, but even for this species the life cycle, except as it occurs in the erythrocyte, and the vector remain unknown. Study of slides from the blood of two species of Formosan frogs, Rana guentheri and R. limnocharis, revealed Dactylosoma ranarum in the former, and what appeared to be a new species, for which the name Dactylosoma taiwanensis is proposed, in the latter. Rana limnocharis has not previously been known to be a host of Dactylosoma, nor has this genus of parasite been reported from Formosa. Dactylosoma ranarum, though not known from many species of frogs and toads, occurs in Asia, Africa, Europe, and in Central and South America. This suggests that it must have been a parasite of Anura for a very long time. Since frogs and toads are incapable of long migrations and are very intolerant of salt water, so wide a distribution may also have palaeogeographic significance.

Notes: SYNOPSIS. The formation of chains was induced both in exponentially growing and in synchronized cultures of Tetrahymena Pyriformis GL, by application of one or two hr 34°C shocks. An arrest in constriction along the division furrow is brought about as a result of prolonged exposure to 34° during an early phase of cell division.After return to optimal temperatures, the chains remain in their original tandem configuration. They possess two sets of cortical structures, and generally also two macronuclei.Subsequently, two new oral primordia appear, one in each component. These primordia develop in synchrony with each other. The later development of the chains is correlated with the placement of the oral primordia. In some situations, these primordia form immediately posterior to the pre-existing oral areas and replace them; in these cases, the original division furrow is obliterated, and irregular and probably unstable homopolar doublets form. More frequently, one or both of the oral primordia are normal division primordia. In these cases, the original oral area of the anterior component persists, while that of the posterior component is resorbed. The original fission line persists, and two new fission lines are formed anterior to each of the new oral primordia. When constriction takes place along the new fission lines, the original arrested fission line is occasionally reactivated, and the chain then divides into four cells. More often, the original furrow is not reactivated (or only incompletely reactivated), and the chain divides into two or three cells, depending on how close the two new division furrows are to each other.The chains ultimately give rise to normal clones of singlet cells. No clones of doublets were observed.In the Discussion, the synchronization of developmental events in the two components of the chain is emphasized. The cases of reactivation of the original fission line in synchrony with constriction along the newly formed fission lines seem to indicate that furrowing results from an interaction of a preformed cortical site (fission line) with a pervasive substance which acts to trigger constriction.

Notes: SYNOPSIS. Studies were carried out on the introduction of labeled precursors into the DNA of Paramecium aurelia (syngen 4, stock 51) by way of the bacteria that are used for food. A thymine-requiring strain of Escherichia coli (15 T−) was labeled by growth in either H3-methyl thymidine or 2-C14 bromouracil, washed free of the exogenous label, and fed to the paramecia. The tritium label from the bacteria was incorporated almost exclusively into the DNA of the paramecia, whereas it was much less specifically incorporated when introduced directly from the medium. The Cu label from bromouracil was also incorporated mainly into the DNA of the paramecia although a small amount appeared in RNA. The formation of labeled food vacuoles was followed. Food vacuoles were formed at a nearly constant rate, with the total number of vacuoles increasing throughout the cycle. The lifetime of the vacuoles was about 2.5 hours. Incorporation of the label into the DXA of the paramecia begins within a few minutes of the formation of the first labeled vacuole. DNA synthesis begins about 1.5 hr after the previous fission (total cell cycle about 5.8 hr) and progresses at a nearly constant rate throughout the remainder of the cycle.

Notes: SYNOPSIS. A method for the in vitro culture of O. purkynei was developed which permitted the continuous culture of this protozoon in clone culture for a. period of 32 months. The shortest division time was 24 hr. The concentration of cells varied between 700 and 1000/ml in the routine procedure. Variations in spination which occurred in the clone culture suggested that this characteristic was of doubtful taxonomic importance.Ground wheat and alfalfa served as substrates but soluble sugars did not. Green plant material appeared to be necessary for continued growth of the protozoa. Ingestion of a large streptococcus was demonstrated by vital staining of a mixed population of bacteria with tetrazolium prior to incubation with the protozoan suspension in the presence of wheat. O. purkynei can tolerate exposure to variations in osmotic pressure, temperature, and oxygen which are consonant with its transfer in nature by grooming or ingestion of contaminated food or drink.

Notes: SYNOPSIS. After several years of field work devoted primarily to determining the incidence of infection of the common milkweed Asclepias syriaca with the trypanosomatid Phytomonas elmassiani, the life cycle of this parasite was determined under controlled conditions. Upon ingestion of phytomonads by the bug Oncopeltus fasciatus, reproduction apparently ceases but growth of individual phytomonads continues until they assume relatively giant proportions. Ten days after ingestion, giant forms are found in the hemocoel of the bug and by 12 days similar forms are present in the salivary glands. In this latter organ, unequal fission takes place with the ultimate formation of numerous forms similar to those found in the plant. Within 2 weeks after these infected bugs had fed on milkweeds, parasites were detected in the latex of formerly non-parasitized plants. The lack of reproduction in the alimentary tract, the formation of giant forms, and the migration through the hemocoel to the salivary glands contrast markedly with the development of Leptomonas oncoptlti in the same bug. In the latter organism, budding leads to the formation of leishmaniform organisms which pass out with feces and are presumably the infective stage of the leptomonad.

Notes: SYNOPSIS. The division delay responses of Tetrahymena (“set-back” curves) which result from heat shocks of the type used in synchronizing studies have been examined in logarithmic and synchronized T. pyriformis GL. The curves indicate an increasing sensitivity to heat shocks with increasing cell age, a sudden sharp increase just prior to the “transition point” and a loss of sensitivity at the transition point. A correlated study of morphogenesis in the synchronous generation suggests that the sudden increase in thermal sensitivity before the transition point is due to a dedifferentiation and redifferentiation of the developing oral primordium which can be induced at this time. The results also suggest that the “stabilization” of the primordium which follows the transition point may occur at more than one developmental stage, i.e., is not stage-specific. It is suggested that stabilization may therefore be due to conditions lying outside the primordium.