ALBERT

Notes: The equilibrium thermodynamics of the reaction:And the equilibrium constant is composed of activities formulated using ideal mixing on sites. Consideration is given to the evaluation of uncertainties in pressures calculated using the geobarometer. Preliminary testing suggests that the geobarometer has considerable potential. Much wider testing is now required.

Notes: Abstract. Pink piemontite-spessartine-bearing and grey-green spessartine-bearing manganiferous quartzose schists derived from siliceous pelagites, and green quartzofeldspathic schists, are described from the greenschist facies of the Haast Schist terrane, near Arrow Junction, western Otago. Electron microprobe data are reported for sphene, spessartine-rich garnet, manganoan epidote, piemontite, tourmaline, phengitic muscovite, chlorite, albite, haematite, rutile, manganoan calcite and chalcopyrite.Metamorphism occurred at about 6.4kbar, 400°C. Xco2 was above the quartz-rutile-calcite-sphene buffer (Xco2± 0.02) throughout the recorded metamorphic history of the piemontite schists. It dropped from above to below this critical buffering value in a spessartine-rich schist and it was close to or below the buffering value in the quartzofeldspathic schists. Production of piemontite required high fO2, believed to be inherited from MnOx in the parent pelagite. Substantial loss of O2 (e.g. minimum of 0.19% by weight in one rock) during diagenesis and/or metamorphism is inferred. In the grey-green schists this inhibited piemontite formation. Slight loss of O2 and Ca2+ accompanied minor late-stage replacement of piemontite by second generation spessartine. Observed zoning and mineral replacements indicate rise of temperature, drop in pressure, or invasion by solutions of lower fO2 and XCO2 equilibrated with surrounding schists.The detailed chemistry of the minerals studied correlates with available Mn and with bulk-rock (Fe3+ x 100)/(Fe2++ Fe3+). The oxidation ratio ranges from 24 in average green quartzofeldspathic schist, through 78 in average grey-green manganiferous quartzose schist, to almost 100 in some piemontite-bearing schists. As Fe2+ gives way to Fe3+, Mg/Fe ratios tend to rise in chlorite, phengite, tourmaline, spessartine, and calcite, Mn increases and Ti decreases in haematite, Mn increases in spessartine and calcite, and Fe increases in rutile. Available divalent cations are depleted relative to Al; chlorite is more aluminous, and phengite more paragonitic than in typical Haast schists.

Notes: Field, petrographic and microprobe investigations of metaclastic rocks, calcareous schists, marbles, chloritic calcareous meta-volcanic units and schists/paragneisses which crop out along the eastern portion of the Central East-West Cross Island Highway in Taiwan demonstrate that metamorphic intensity gradually increases eastward. The lower greenschist facies Slate Formation on the W contains completely recrystallized, pure albitic plagioclase, but at least some of the white micas (± chlorites) probably represent relict detrital flakes. Neo-blastic biotite and epidote occur sporadically in the Pihou(?) Formation, and increase dramatically eastward; concomitantly the abundance of carbonaceous matter decreases to zero in the eastern Tailuko zone, and the amount of chlorite + white mica diminishes somewhat. Epidote becomes more aluminous at higher metamorphic grade. Eastward, phengites change progressively to more muscovitic compositions as the proportion of biotite increases.A close approach to chemical equilibrium for the pre-Cenozoic, complexly deformed metamorphic basement assemblages is suggested by regular, systematic, major and minor element partitioning between analysed coexisting phases. Fractionation is less pronounced on the E, reflecting higher temperatures. Estimated physical conditions of recrystallization with αH2O and αCO2 moderate, are: T 〉 325 ± 75°C, P 〉 3 kbar (W); T 〉 425 ± 75°C, P 〉 4kbar(E).The gradual eastward increase in metamorphic intensity from the Slate Formation through the Pihou(?) Formation and the three Tailuko zones, as well as the relict precursor textures in the pre-Cenozoic layered basement rocks indicate that the observed paragenetic sequence could represent a synchronous Neogene recrystallization event, probably accompanying the Plio-Pleistocene collision of the Asiatic continental margin and the Luzon (Coastal Range) andesitic arc.

Notes: The structure, microstructure and petrology of a small area close to the village of Bard in Val d'Aosta (Italy) has been studied in detail. The area lies across the contact between the Gneiss Minuti (GM) and the Eclogitic Micaschist (EMS) Complexes of the Lower element of the Sesia portion of the Sesia-Lanzo Zone (Western Alps). Both complexes have undergone high-pressure metamorphism, but the metamorphic assemblages indicate a sudden increase in pressure in going across the contact from the GM to the EMS. Therefore, we interpret the contact as a thrust dividing the lower element of the Sesia into two sub-elements. This interpretation is supported by structural evidence.The early Alpine (90-70 Ma) metamorphic history is best preserved in the EMS and is one of increasing pressure associated with thrusting. The maximum P/T recorded in the EMS is 〉1500 MPa (〉15kbar) and 550°C and in the GM is 〈 1500-1300 MPa (〈 15-13 kbar) and 500-550°C. We suggest that the rocks were probably in an active Benioff zone during this time.From then on the histories of the GM and EMS are the same. Deformation continued and the thrust and thrust slices were folded during decreasing pressure. We interpret the first postthrusting deformation in terms of uplift associated with continued shortening of the crust and underplating after the Benioff zone had become inactive and a new Benioff zone had developed further to the north-west.A still later deformation and the Lepontine metamorphism (38 Ma) are related to continued uplift. Much of this deformation is characterized by structures indicative of vertical shortening and lateral spreading as the mountains rose above the general level of the surface.

Notes: In the Boi Massif of Western Timor the Mutis Complex, which is equivalent to the Lolotoi Complex of East Timor, is composed of two lithostratigraphical components: various basement schists and gneisses; and the dismembered remnants of an ophiolite. Cordierite-bearing pelitic schists and gneisses carry an early mineral assemblage of biotite + garnet + plagioclase + Al-silicate, but contain no prograde muscovite; sillimanite occurs in a textural mode which suggests that it replaced and pseudomorphed kyanite at an early stage and some specimens of pelitic schist contain tiny kyanite relics in plagioclase. Textural relations between, and mineral chemistries of, ferro-magnesian phases in these pelitic chists and gneisses suggest that two discontinuous reactions and additional continuous compositional changes have been overstepped, possibly with concomitant anatexis, as a result of decrease in Pload during high temperature metamorphism. The simplified reactions are: garnet and/or biotite + sillimanite + quartz + cordierite + hercynite + ilmenite + excess components. P-T conditions during the development of the early mineral assemblage in the pelitic gneisses are estimated to have been P + 10 kbar and T 〉 750°C, based upon the plagioclase-garnet-Al-silicate-quartz geobarometer and the garnet-biotite geothermometer. P-T conditions during the subsequent development of cordierite-bearing mineral assemblages in the pelitic gneisses are estimated to have been P + 5 kbar and T + 700°C with XH2O 〈 0.5, based upon the Fe content of cordierite occurring in the assemblage quartz + plagioclase + sillimanite + biotite + garnet + cordierite coexisting with melt.Final equilibration between some of the phases suggests that conditions dropped to P 〉 2.3 kbar and T 〉 600°C. A similar exhumation P-T path is suggested for the pelitic schists with early metamorphic conditions of P 〉 6.2 kbar and T 〉 745°C and subsequent development of cordierite under conditions in the range P = 3-4 kbar and T = 600-700°C. The tectonic implications of these P-T estimates are discussed and it is concluded that the P-T path followed by these rocks was caused by decompression during rifting and synmetamorphic ophiolite emplacement resulting from processes during the initiation and development of a convergent plate junction located in Southeast Asia during late Jurassic to Cretaceous time.

Notes: Plagioclase compositions vary from An0.1–2.5 to An32 with increasing grade in chlorite zone to oligoclase zone quartzofeldspathic schists, Franz Josef-Fox Glacier area, Southern Alps, New Zealand. This change is interrupted by the peristerite composition gap in rocks transitional between greenschist and amphibolite facies grade. Oligoclase (An20-24) and albite (An0.1–0.5) are found in biotite zone schists below the garnet isograd. With increasing grade, the plagioclase compositions outline the peristerite gap, which is asymmetric and narrows to compositions of An12 and An6 near the top of the garnet zone. In any one sample, oligoclase is the stable mineral in mica-rich layers above the garnet isograd, whereas albite and oligoclase exist in apparent textural equilibrium in adjacent quartz-plagioclase layers. The initial appearance of oligoclase in both layers results from the breakdown of epidote and possibly sphene. Carbonate is restricted to the quartz-plagioclase rich layers and probably accounts for the more sodic composition of oligoclase in these layers. The formation of more Ca-rich albite and more Na-rich oligoclase near the upper limit of the garnet zone coincides with the disappearance of carbonate and closure of the peristerite gap. Garnet appears to have only a localized effect on Ca-enrichment of plagioclase in mica-rich layers within the garnet zone. The Na-content of white mica increases sympathetically with increasing Ca-content of oligoclase and metamorphic grade.Comparison of the peristerite gap in the Franz Josef-Fox Glacier schists and schists of the same bulk composition in the Haast River area, 80 km to the S, indicates that oligoclase appears and epidote disappears at lower temperatures, and that the composition gap between coexisting albite and oligoclase is narrower in the Franz Josef-Fox Glacier area. It is suggested that a higher thermal gradient (38-40°C/km) and variations in Si/Al ordering during growth of the plagioclases between the two areas may account for these differences. In the Alpine schists the peristerite gap exists over a temperature and pressure interval of about 370-515°C and 5.5-7 kbar (550-700 MPa) PH2O.

Notes: Sapphirine occurs in a 3-5 m wide zone between amphibole-lherzolite and garnetiferous metagabbro at Finero in the Ivrea Zone, NW Italian Alps. Layers consisting of plag + hb + sa + cpx + opx + sp + gt are interbanded with spinel pyroxenites, which may contain sapphirine replacing spinel. All minerals are very magnesian, with XMg between 0.78 and 0.92. Bulk rock analyses suggest that precursors to the sapphirine-bearing rocks were igneous cumulates of plagioclase + olivine + hornblende + spinel. Up to 16wt% CaO does not inhibit sapphirine formation and it is the unusually Mg-rich nature of the host rocks which allows sapphirine development. The early igneous assemblage was replaced by one of cpx + sa + hb +± plag at a pressure of 9 ± 1 kbar and temperatures of 900 ± 50°C. Subsequent rapid uplift caused the instability of gt, gt + hb, hb and sa + cpx to form opx + plag ± sp ± sa symplectites.

Notes: The Gran Paradiso basement complex of the French and Italian Alps is composed of metasediments, termed the gneiss minuti, and metabasic rocks, both of which are intruded by a late Hercynian granite. The Bonneval gneiss, which crops out at the western edge of the complex, is composed of highly deformed metasediments, volcanics and volcaniclastic rocks. Eclogites, now highly altered, occur in the metabasic rocks. Kyanite and blue-green amphibole are locally present in the gneiss minuti and aegirine plus riebeckite occur in the Bonneval gneiss. A moderately high pressure - low temperature metamorphic event of probable Alpine age occurred in the basement complex. This metamorphic event differs from that in the overlying Sesia unit and ophiolites of the Schistes lustrés nappe in being at lower pressures (below the ab = jd100+ qz transition) and post-dating the major (D2A) deformation. The origin of the metamorphism is discussed and interpreted as a probable consequence of the overlying nappe pile which was emplaced during the D2A event. Subsequent greenschist facies metamorphism in the basement complex is a consequence of thermal relaxation during uplift.

Notes: Abstract. A method for the quantitative analysis of the spatial relations of minerals is described. Dispersed distributions are formed by annealing and destroyed in post-tectonic migmatization. Aggregate distributions characterize solid-state differentiation, whereas leucosomes formed in systems of high fluid:rock ratio (in the examples studied, anatectic melts) show random distributions.Quantitative textural analysis can be used to indicate whether migmatization was post-tectonic or earlier, though caution is necessary if post-migmatite cooling is slow or if there is some minor deformation. More importantly, it can be used to discriminate melt-present from melt-absent leucosomes; this is exemplified by a suite of metamorphic and anatectic migmatites from the Scottish Caledonides.The textural evolution of anatexites with increasing melt percentage is traced. Initial feldspar porphyroblastesis occurs by Ostwald ripening via grain boundary melts; subsequently ophthalmites develop with fabrics and chemistry inherited from the palaeosome. At greater than 30% melt these inherited fabrics are wholly destroyed. Deformation prompts segregation into melanosome and leucosome; resultant leucosomes contain no inherited crystals. The scale of anatectic systems is fixed at the point at which segregation begins; ophthalmites provide evidence for melt and crystal transfer beyond original palaeosome boundaries. In contrast, metamorphic migmatites are necessarily small-scale systems because of diffusive constraints, and melanosomes are invariably produced.

Notes: The oligoclase-biotite zone of the Bessi area, central Shikoku is characterized by sodic plagioclase (XCa= 0.10–0.28)-bearing assemblages in pelitic schists, and represents the highest-grade zone of the Sanbagawa metamorphic terrain. Mineral assemblages in pelitic schists of this zone, all with quartz, sodic plagioclase, muscovite and clinozoisite (or zoisite), are garnet + biotite + chlorite + paragonite, garnet + biotite + hornblende + chlorite, and partial assemblages of these two types. Correlations between mineral compositions, mineral assemblages and mineral stability data assuming PH2O = Psolid suggests that metamorphic conditions of this zone are about 610 ± 25°C and 10 ± 1 kbar.Based upon a comparative study of mineralogy and chemistry of pelitic schists in the oligoclase-biotite zone of the Sanbagawa terrain with those in the New Caledonia omphacite zone as an example of a typical high-pressure type of metamorphic belt and with those in a generalized‘upper staurolite zone’as an example of a medium-pressure type of metamorphic belt, progressive assemblages within these three zones can be related by reactions such as:

Notes: An assemblage consisting of corundum, sapphirine, spinel, cordierite, garnet, biotite and bronzite is described from the Messina area of the Limpopo Mobile Belt, and consideration given to its petrogenesis. Various geothermometers and geobarometers have been applied in an attempt to determine the temperatures and pressures of metamorphism.A former coexistence of garnet and corundum is suggested to have developed during the earliest high pressure phase of the metamorphism, where temperatures exceeded 800°C and pressures as high as 10kbar may have been experienced. Subsequently, continuous retrograding reactions from medium pressure granulite facies at about 800°C and 8kbar towards amphibolite facies generated spinel, cordierite, sapphirine and possibly also bronzite. The most notable reaction was probably of the form: garnet + corundum = cordierite + sapphirine + spinel.

Notes: A review of currently available information relevant to the Basal Gneiss Complex (BGC) of Western South Norway, combined with the authors’own observations, leads to the following conclusions.1. Most of the BGC consists of Proterozoic crystalline rocks and probably subordinate Lower Palaeozoic cover.2. The last major deformation of these rocks was during the Caledonian orogeny and involved large-scale thrusting, recumbent folding and doming. The structural development of the BGC is closely tied in with that of the Caledonian allochthon.3. The whole eclogite-bearing part of the BGC has suffered a high pressure metamorphism with conditions of between 550°C, 12.5 kbar (Sunnfjord) and about 750°C, 20 kbar (Møre og Romsdal) at the metamorphic climax.4. This metamorphism was of Caledonian age, probably rather early in the Caledonian tectonic history of the BGC and is considered to have been a rather transient event.By setting these conclusions in a framework provided by geophysical evidence for the deep structure of the crust in southern Norway we have constructed a geotectonic model to explain the recorded metamorphic history of the BGC. It is suggested that considerable crustal thickening was caused by imbrication of the Baltic plate margin during continental collision with the Greenland plate. This resulted in high pressure metamorphism in the resulting nappe stack. Progradation of the suture caused underthrusting of the Baltic foreland below the eclogite-bearing terrain causing it to emerge at the Earth's surface, aided by tectonic stripping and erosion.Application of isostacy equations to the model shows that eclogites can be formed by in-situ metamorphism in crustal rocks and reappear at the land surface above a normal thickness of crust in a single orogenic episode of approximately 65-70 Ma duration.

Notes: Detailed geochronological, structural and petrological studies reveal that the geological evolution of the Field Islands area, East Antarctica, was substantially similar to that of the adjacent Archaean Napier Complex, though with notable differences in late and post Archaean times. These differences reflect the area's proximity to the Proterozoic Rayner Complex and consequent vulnerability to tectonic process involved in the formation of the latter. Distinctive structural features of the Field Islands are (1) consistent development of a discordant, pervasive S3 axial-plane foliation; (2) re-orientation of S3 axial planes to approximate to the subsequent E-W tectonic trend of the nearby Rayner Complex; (3) selective retrogression by a post-D3 static thermal overprint; and (4) relatively common development of retrogressive, E-W-trending, mylonitic shear zones.Peak metamorphic conditions in excess of 800°C at 900 ± 100 M Pa (9 kbar) were attained at one locality following, but probably close to the time of D2 folding. D3 took place in late Archaean times when metamorphic temperatures were about 650°C and pressures were about 600 MPa (6 kbar). Later, temperatures of 600 ± 50°C and pressures of 700 MPa (7kbar) were attained in an amphibolite-facies event, presumably associated with the widespread granulite to amphibolite-facies metamorphism and intense deformation involved in the formation of the Rayner Complex at about 1100 Ma. The area was subsequently subjected to near-isothermal uplift.Rb-Sr isotopic data indicate that the pervasive D3 fabric developed at about 2400–2500 Ma, and this age can be further refined to 2456+8-5 Ma by concordant zircon analyses from a syn-D3 pegmatite. All zircons were affected by only minor (〈7–10%) Pb loss and/or new zircon growth during the Rayner event at about 1100Ma. Thus the 450–850 μg/gU concentrations of these zircons were too low to cause sufficient lattice damage over the 1350 Ma (from 2450 Ma) for excessive Pb to be lost during the 1100 Ma event. The emplacement of pegmatite at 522 ± 10 Ma substantially changed the Rb-Sr systematics of the only analysed rock that developed a penetrative fabric during the 1100 Ma event. Monazite in this pegmatite contains an inherited Pb component, which probably resides in small opaque inclusions.A good correlation is found between Rb-Sr total-rock ages and rock fabric. U-Pb zircon intercepts with concordia also mostly correspond to known events. However, in one example a near perfect alignment of zircon analyses, probably developed by mixing of unrelated components, produced concordia intercepts that appear to have no direct geochronological significance.

Notes: An occurrence of quartz-eclogite is described from the Inner Schieferhülle unit of the Pennine Basement Complex in the SE Tauern Window, Austria.Field relations strongly suggest a pre-Alpine age for the primary eclogitic mineral assemblage (garnet + omphacite + quartz + rutile). This implies that there was no connection between the formation of these eclogites and the late Cretaceous and Tertiary tectonic evolution of the Eastern Alps. The quartz-eclogite mineral assemblage crystallized under conditions of 620 ± 100°C and at pressures in excess of 12 kbar, and suffered amphibolitic overprinting of Alpine and possibly Hercynian age.A four-stage polymetamorphic history is proposed for the Inner Schieferhülle:

Notes: Mafic and ultramafic xenoliths in a basaltic cone at The Anakies in south-eastern Australia are geochemically equivalent to continental basaltic magmas and cumulates. The xenolith microstructures range from recognizably meta-igneous for intrusive rocks to granoblastic for garnet pyroxenites. Contact relationships between different rock types within some xenoliths suggest a complex petrogenesis of multiple intrusive, metamorphic and metasomatic events at the crust/mantle boundary during the evolution of south-eastern Australia. Unaltered spinel lher-zolite, typical of the uppermost eastern Australian mantle, is interleaved with or veined by the metamorphosed intrusive rocks of basaltic composition.Geothermobarometry calculations by a variety of methods show a concordance of equilibration temperatures ranging from 880°C to 980°C and pressures of 12 to 18 kbar (1200-1800 mPa). These physical conditions span the gabbro to granulite to eclogite transition boundaries. The water-vapour pressure during equilibration is estimated to be about 0.5% of the load pressure, using amphibole breakdown data. Large fluid inclusions of pure CO2 are abundant in the mineral phases in the xenoliths, and it is suggested that flux of CO2 from the mantle has been an important heat source and fluid medium during metamorphism of the mafic and ultramafic protoliths at the lower crust/upper mantle boundary.The calculated pressures and temperatures suggest that the south-eastern Australian crust has sustained a high geothermal gradient. In addition, the nature of the mineral assemblages and the contact relationships of granulitic rock with spinel lherzolite, characteristic of mantle material, suggest that the Moho is not a discrete feature in this region, but is represented by a transition zone approximately 20 km thick. These inferences are in agreement with geophysical data (including seismic, heat-flow and electrical resistivity data) determined for south-eastern Australia.Underplating at the crust/mantle boundary by continental basaltic magmas may be an important alternative or additional mechanism to the conventional andesite model for crustal accretion.

Notes: Abstract. In the Kamuikotan zone, central Hokkaido, Japan, two distinct types of metamorphic rocks are tectonically mixed up, along with a great quantity of ultramafic rocks; one type consists of high-pressure metamorphic rocks, and the other of low-pressure ones. The high-pressure metamorphic rocks are divided into two categories. (1) Prograde greenschist to glaucophaneschist facies rocks derived from mudstone, sandstone, limestone, a variety of basic rocks such as pillow and massive lavas, hyaloclastite and tuff, and radiolarian (Valanginian to Hauterivian) chert, among which the basic rocks and the chert, and occasionally the sandstone, occur as incoherent blocks (or inclusions) enveloped by mudstone. (2) Retrograde amphibolites with minor metachert and glaucophane-calcite rock, which are tectonic (or exotic) blocks enclosed within prograde mudstone or serpentinite, or separated from these prograde rocks by faults. The K-Ar ages of the prograde metamorphic rocks (72, 107 and 116 Ma on phengitic muscovites) are younger than those of the retrograde rocks (109, 132, 135 and 145 Ma on muscovites, and 120 Ma on hornblende). The low-pressure metamorphic rocks consist of the mafic members of an ophiolite sequence with a capping of radiolarian (Tithonian) chert with the metamorphic grade ranging from the zeolite facies, through the greenschist (partly, actinolite-calcic plagioclase) facies to the amphibolite (partly, hornblende-granulite) facies. The low-pressure metamorphism has a number of similarities with that described for‘ocean-floor’metamorphism. The tectonic evolution of such a mixed-up zone is discussed in relation to Mesozoic plate motion.

Notes: The rocks of the Scourian Complex have been intensively studied, but there is still no consensus as to the conditions of the granulite-facies metamorphism preserved in these rocks. Recent estimates of these conditions fall into two groups, one at 820-920°C and ca. 11 kbar and the second at ca. 1000°C and 〉12 kbar. Investigation of a variety of rocks shows that the recorded conditions vary with grain-size, with higher-grade conditions recorded by the cores of coarser (ca. 10 mm) crystals, and lower-grade conditions recorded by the rims of coarser grains and by finer grains. This observation suggests that re-equilibration during recovery of these rocks to the surface has been important which may account for the discrepancy in estimated P-T conditions. Revised estimates of the equilibration conditions of the Scourian Complex of T 〉 1000°C and P 〉 8.5 kbar are presented. The conditions suggested for the peak of metamorphism mean that the role of anatexis in the genesis of these rocks must be considered and the nature of the fluid phase thoroughly investigated.

Notes: Abstract. Plagioclase porphyroblasts from silvergrey schists belonging to the Nevado Filabride Complex in the Sierra Alhamilla (Betic Zone, SE Spain) are interpreted as having been formed preand synkinematically with respect to the second phase of deformation. Different types of inclusion patterns represent 'snap-shots’(high growth-rate/strain-rate ratio features) of the formation of a diffentiated crenulation cleavage during this second phase of deformation, by the processes of kinking, crenulation and associated differentiation.Regional considerations indicate an Alpine age for this tectono-metamorphic event, which can be explained by the‘hot emplacement’of the higher Nevado Filabride units. The observed structural evolution is not consistent with a pre-Alpine polyphase deformation history.

Notes: Evidence from rock microstructures, mass transfer and isotopic exchange indicates that substantial quantities of aqueous fluids are involved in low- and medium-grade regional metamorphism. Similar conclusions are drawn from many retrograde environments, whereas high-grade metamorphic fluids may be melt dominated. The mobile fluids play essential roles in metamorphic reactions, mass transport and deformation processes. These processes are linked by the mechanical consequences of metamorphic fluid pressures (Pf) generally being greater than or equal to the minimum principal compressive stress. Under such conditions metamorphic porosity comprises grain boundary tubules and bubbles together with continuously generated (and healed) microfractures. Deformation results in significant interconnected porosity and hence enhanced permeability. Lithologically and structurally controlled permeability variations may cause effective fluid channelling.Simple Rayleigh-Darcy modelling of a uniformly permeable, crustal slab shows that convective instability of metamorphic fluid is expected at the permeabilities suggested for the high Pf metamorphic conditions. Complex, large-scale convective cells operating in overpressured, but capped systems may provide a satisfactory explanation for the large fluid/rock ratios and extensive mass transport demonstrated for many low- and medium-grade metamorphic environments. Such large-scale fluid circulation may have important consequences for heat transfer in and the thermal evolution of metamorphic belts.

Notes: Hydrothermal synthesis of Fe-pum-pellyites was conducted using high pressure cold-seal apparatus and solid oxygen buffering techniques at temperatures between 250°C and 550°C and 2.0–9.1 kbar Pfluid. Fe-pumpellyites were synthesized from partially crystalline gel mixtures of compositions: 4CaO - 2.1Al2O3_1.5FeO - 0.3MgO - 6SiO2 (II) and 3CaO - 1.5 Al2O3 - 2.7FeO - 0.3MgO - 6SiO2 (III) in the presence of excess H2O at Pfluid of 5–9.1 Kbar, temperatures between 275°C and 325°C, and fO2 defined by the QFM and HM buffers; for both of these compositions (II and III), the condensed synthetic run products included minor 7Å chlorite ± garnet ± Fe-oxide. The cell dimensions and aggregate refractive index (a= 19.13(2)Å, b= 5.940(4)Å, c= 8.847(5)Å, ±= 97.37(6)±, and n= 1.702(2)) of the pum-pellyite synthesized from the bulk composition II mix are compatible with those of natural pumpellyites containing similar total Fe contents. Attempts at synthesizing Fe-pumpellyites from a Mg-free bulk composition were not successful; these results are consistent with the total absence of natural Mg-free pumpellyites.The higher temperature, higher oxygen fugacity assemblages of the equivalent bulk compositions (II and III) consist of epidote ± minor amounts of chlorite, garnet, quartz, hematite, and magnetite. The results of these synthesis experiments accord with the mineral parageneses observed in low-grade metabasites which imply that Fe-pumpellyites are replaced by epidote with increasing temperature and/or fO2 and that Fe3+ is preferentially partitioned into epidote with respect to coexisting pum-pellyite. In addition, these synthesis experiments indicate that Fe-bearing pumpellyites crystallize at and are stable to lower temperatures than more aluminous pumpellyites—a result also consistent with natural systems.

Notes: The author describes the responsibilities of the forester both for the production of timber and the preservation of natural resources, and shows how aerial photographs can assist in supplying the information required for organising the management of forest areas. On limited experience with infrared and colour films, the author compares them with panchromatic film for aerial photography of forest country; he considers that in most cases good definition is the most desirable quality in such photographs, although special contrast effects may be useful for particular purposes.

Notes: A brief description is given of the history of the stereocomparator, followed by a comparison of the major features of five modern instruments: the Wild STK 1, Nistri TA 3 and TA 3/A, S.O.M., Zeiss PSK 1 and Hilger and Watts stereocomparators. Special attention is paid to the production model of the Hilger and Watts stereocomparator, which differs in several important respects from the prototype.

Notes: Three unrelated matters are discussed. Firstly, the recent rapid advances in the application of precision engineering, electronics and digital computers to photogrammetric surveying operations are shown to be likely to result in a change of emphasis; from the need for great skill in making each particular map, to the need for even greater skill in making machines which, once made, will make many maps, largely automatically. This in turn is likely to have far-reaching effects on the type and training of persons employed in the profession. Secondly, an example is quoted which suggests that the value of photogrammetric methods, as an aid to the work of professions other than land surveying, is not sufficiently recognised by the teaching faculties of some of our universities. Ways and means of improving the situation are considered. Thirdly, after a brief historical survey of the birth and growth of the Photogrammetric Record, arguments for and against some possible changes in editorial policy are stated and certain conclusions reached.

Notes: Book reviews in this article:GEODESY. By Brigadier G. Bomford.INTERNATIONAL YEAR BOOK OF CARTOGRAPHY (Vol. II, 1962). Editor, Eduard Imhof.MODERN COMPUTING METHODS. National Physical Laboratory: Notes on Applied Science.SCIENTIFIC PHOTOGRAPHY. Editor, H. Sauvenier.

Notes: Underwater photogrammetry is being used in the particularly hostile environment of the North Sea where it has been put into commercially viable operation. The authors discuss underwater photogrammetry related to other means of inspection of oil platforms. They also deal with operational experience of 35 mm and 70 mm cameras, camera calibration, the provision of control and photogrammetric observations and data analysis. The demand for underwater photogrammetry continues to grow.

Notes: This paper summarises the theoretical and practical development of’an analytical system for close range photogrammetry. The system uses the extended bundle method of phototriangulation and a sophisticated least squares algorithm. A description is given of computer software, and aspects of statistical testing and gross error detection are discussed in order to assess the accuracy potential. Applications of the system, for precise co-ordination of a target range and camera calibration are outlined.

Notes: A photogrammetric system that is suitable for shallow water detailed mapping at scales from 1:50 to 1:500 for coastal and harbour engineering projects is described. The results from tests using automatic 35 mm Canon cameras on an elevated platform to determine the accuracy of planimetric and depth co-ordinates are presented. The economic benefits of stereophotography through shallow water rather than underwater photography are discussed.

Notes: This paper reviews the growth in the use of photogrammetric techniques in architecture, principally in the United Kingdom, over the past ten years. The work of the various establishments involved in architectural photogrammetry is described and the results of a questionnaire, distributed within the architectural profession, are analysed. Some comparisons are made with developments elsewhere in Europe.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn examine dans cet article l'extension qu'a connue l'utilisation des méthodes photogrammétriques en architecture au cows des dix dernières années, principalement dans le Royaume-Uni. On y décrit les travaux des divers organismes impliqués dans la photogrammétrie architecturale et l'on y analyse les résultats d'un questionnaire diffusé au sein de la profession liée à l'architecture. On fournit enfin quelques comparaisons avec les développements constatés par ailleurs en Europe.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird über die zunehmende Anwendung photogrammetrischer Verfahren während der letzten 10 Jahre in der Architektur, insbesondere im Vereinigten Königreich, berichtet. Die Arbeit verschiedener Institutionen, die sich mit Architekturphotogrammetrie befassen, wird beschrieben, und es werden die Ergebnisse eines unter Architekten verteilten Fragebogens analysiert. Weiterhin werden Vergleiche zu Entwicklungen in anderen europäischen Ländern gezogen.

Notes: SYNOPSIS. A chemically defined culture medium has been developed for the soil amoeba Hartmannella rhysodes Singh which contains the minimum essential organic requirements for growth. The medium consists of 7 amino acids, 3 vitamins, a carbon source (e.g. glucose) and inorganic salts.

Notes: SYNOPSIS. A mutant strain of Astasia longa utilized glucose for growth whereas the parent (J) strain did not. The optimal pH for growth of the mutant with glucose (sole carbon source) was near neutrality; the optimal glucose concentration 0.02 M. Cell-free extracts or cell homogenates produced C14O2 when incubated in the presence of C14-labeled glucose. On the other hand, after incubation with C14-labeled glucose, intact parent cells and their respiratory CO2 showed no radioactivity while the mutant-strain cells and CO2 produced were active. Dissimilation of glucose-1-C14 and glucose-6-C14 yielded the same amount of radioactivity in metabolic CO2 in cell-free extracts of both strains. Of five enzymes assayed, hexokinase, phosphoglucomutase, and lactic dehydrogenase were present whereas glucose-6-PO4 dehydrogenase and glucose dehydrogenase were absent in cell homogenates of both strains. Presumably these two strains of A. longa differ in permeability of the plasma membrane. Further tracer and enzyme studies indicated that the Embden-Meyerhof scheme is the principal pathway of glucose catabolism; the hexose mono-phosphate shunt and the direct oxidative pathway were either not operating or quantitatively insignificant.

Notes: SYNOPSIS. By means of electron microscopy, a study has been made of the fine structure of the macrogametocytes, microgametocytes and oocysts of Eimeria perforans from the intestine of the wild rabbit (Oryctolagus cuniculus). The parasites lie in a vacuole within the host cell. The surface of the gametocytes is not plain, but displays irregular protrusions. A large intranuclear body can be detected within the macrogametocytes. Similar structures are also found within the cytoplasm. Within the latter there exists a large spread out reticulum, the channels and vesicles of which concentrate especially close to the nuclear membrane. Tubuli are seen in the numerous mitochondria, which often have a dumb-bell shape.In most of the gametocytes irregular, strongly osmiophilic lipid inclusions are observed, which always are surrounded by the endoplasmic reticulum. Strange folded ovoid bodies are found within the cytoplasm of the oocysts. Nothing can be told with certainty of their nature and function. Probably they represent specific storage bodies.

Notes: SYNOPSIS. Tritrichomonas foetus survived much better on extended storage at -95 than at -28d̀C following slow freezing in the presence of 1.0 M glycerol. There was no significant difference between these temperatures in survival up to 8 days, but thereafter the protozoa continued to die off slowly at -28d̀, whereas their numbers remained essentially constant at -95d̀ for 128 to 256 days. The trichomonads' motility was much better after storage at -95d̀ than after storage at -28d̀, and fresh cultures could be initiated from the former much more readily.Other constituents of the suspending medium besides glycerol affect the survival of the protozoa upon freezing. Survival was much better when the protozoa were frozen in the original Diamond's trypticase-yeast extract-maltose-cysteine-ascorbic acid-serum medium in which they had been grown than when they were frozen in physiological salt solution or in fresh Diamond's medium. There was no significant difference between survival in the latter two suspending media. The speed and time of centrifugation needed to remove the trichomonads from the medium in which they had been grown had no effect on their survival upon subsequent freezing. Presumably some product or products of the trichomonads' metabolism have an additional protective action which supplements that of glycerol.When frozen in the original Diamond's medium in which they had been grown plus 1.0 M glycerol, an average of 15% of the trichomonads were alive after 128 days' storage at -28d̀ and an average of 38% were alive at -95d̀C. When frozen in physiological salt solution plus 1.0 M glycerol, these percentages were 8% and 12% respectively.

Notes: SYNOPSIS. When Spathidium spathula was exposed to X-ray doses ranging from 1–25 kr this animal was found to be more radiosensitive than any ciliate previously reported. A dose of 1 kr is sufficient to increase the time of the first generation from 5 to about 5 1/2 hours. A dose of 4 kr is enough to approximately double the generation time. Bacteria in the medium during irradiation do not protect the ciliate against injury. Animals irradiated as dry cysts are only slightly more resistant than vegetative forms, requiring 10 kr to double the generation time. One day after exposure, irradiated lines are uniformly poor in growth rate (0–2 daily divisions), but later a bimodal response is noticed, some lines remaining poor and others recovering. Within 24 hours after treatment, a number of irradiated animals show structural abnormalities and are greatly increased in size. The experiments have not determined the reason for the high sensitivity of Spathidium but have made certain alternatives unlikely.

Notes: SYNOPSIS. When Tetrahymena suspended in water were given increasing doses of radiation, oxygen consumption decreased with increasing dose, reaching 60–90% at 600,000 r. Cells irradiated in 0.07 M phosphate buffer, pH 7.4, showed no significant decrease in oxygen consumption even at 600,000 r. The decrease in respiration observed on irradiation of Tetrahymena pyriformis W in water with 300,000 r of X-radiation was prevented by addition of pyruvate or acetate during or immediately after irradiation. Pyruvate stimulated the respiration of the X-irradiated cells, particularly at 10 and 60 min post-irradiation.Lactate markedly stimulated the respiration of control suspensions of Tetrahymena cells and oxidation of lactate by cells irradiated with 300,000 r was increased by 20 to 100%, depending on the concentration of lactate and the time after irradiation. Pyruvate was considerably more effective than lactate in increasing O2 uptake of X-irradiated cells, particularly at 10 min post-irradiation. Thioctic acid affected neither the respiration of control or X-irradiated Tetrahymena nor the oxidation of pyruvate.The growth lag of Tetrahymena increased proportionately with increasing radiation dose; no cells survived 600,000 r. The presence of metabolites during irradiation did not affect the lag period or subsequent growth rates. The effects observed were discussed in terms of an alteration of the permeability of Tetrahymena after irradiation.

Notes: SYNOPSIS. A full account of the nuclear changes during binary fission and conjugation in a local race of Blepharisma is presented in this paper. The macronucleus consists of 2 nodes connected by a strand. Number of micronuclei varies from 6 to 18. During binary fission, condensation of macronucleus is followed by elongation and thinning of the middle region which finally breaks. Daughter nuclei later attain the typical vegetative form. Notably, during binary fission some micronuclei appear to complete their mitoses by the time the macronucleus attains the condensed form, while others lag behind and exhibit practically every stage of mitosis.During conjugation, from 6 to 10 micronuclei undergo the first pregamic division, the same number through the second division, and two products of the second division take part in the third division. The rest degenerate. Division products of the nuclei in the paraoral region take part in synkaryon formation. The synkaryon undergoes either 2 or 3 divisions. In the former case, of the 4 products, 2 become the macronuclear anlagen, one the micronucleus and the fourth degenerates. In the latter case, of the 8 products, 3 to 4 become the macronuclear anlagen and the rest become micronuclei. Chromatin elimination has been observed during the division of the macronuclear anlage, followed by an extra metagamic fission of the cell.Comparison with two other races from India and an American race indicates considerable diversity in the structure and behaviour of the nuclear apparatus in different races of Blepharisma undulans.

Notes: SYNOPSIS. Females of Heterakis gallinae were separated on the basis of their capacity to transmit the protozoan parasite Histomonas meleagridis. Sections of worms, capable of transmitting the protozoon, revealed the organism in both males and females as well as in the eggs. Infected male worms contained histomonads in the gut wall and the wall and lumen of the reproductive system. Female worms infected with H. meleagridis showed the organisms throughout the reproductive system. Histomonads, found in uterine eggs possessing shells, had a larger nucleus and reduced cytoplasm.Because of the presence of the protozoon among the sperm in the male reproductive system, it is believed the organism can be transmitted to female worms through copulation. The cycle in the worms also supports the assumption that H. meleagridis was originally a parasite of the worm.

Notes: SYNOPSIS. Speculations regarding the mode of transmission of monocystid parasites of earthworms over a period of more than 100 years have never been tested experimentally under controlled conditions. In order to do so a stock of infectionfree Eisenia foetida (Sav.) was raised from cocoons and experimental infections were induced in this host using sporocysts of the gregarine parasites Apolocystis elongata Phillips & Mackinnon 1946, and Nematocystis elmassiani (Hesse, 1909). Experimental infections were obtained by feeding to uninfected worms sporocysts obtained directly from infected host worms. This proved that the intervention of a vector is not a necessary condition of infection. Infections could not be induced by injecting sporocysts through the body wall into the body cavity. Infections are thus probably acquired in nature by the ingestion of sporocysts. Sporocysts do not leave the body of the host by being passed from coelom to lumen of the gut, nor do they pass directly to the exterior through apertures of the body wall. There was no evidence of parasitic autotomy. It is therefore concluded that death and decay of the host is the normal method of dissemination of sporocysts. Sporocysts were not infective after drying in air for three weeks. Other sporocysts lost potency after storage in moist conditions for several months. Infections involving the organisms specified were sporadic and unpredictable; modifying factors, such as variations in host susceptibility and latency in infection, appeared to be operating.

Notes: SYNOPSIS. By an automatic electronic technique—the Flying Spot Particle Resolver—the effect of a wide range of concentrations of vitamin B12 on the size and growth of the B12-dependent Euglena gracilis was studied. Rate of cell growth was directly proportional, and cell size inversely proportional, to B12 concentration. Gross B12 depletion resulted in gigantism and prolongation of generation times.

Notes: SYNOPSIS. Previously, the reproduction-inhibiting effects of ablastin could only be shown in vivo. The present report describes techniques for the in vitro demonstration and titration of this antibody. With a medium composed of Hanks' balanced salt solution, rat serum, lactalbumin hydrolysate, yeast extract and rat blood lysate, blood stream forms of Trypanosoma lewisi can be grown for approximately 24 hours at 37d̀C. Starting with the medium containing normal rat serum and inoculated with adult (inhibited) trypanosomes from infected rat blood, 50% or more of the parasites are in various stages of division after incubation overnight. Under similar conditions with ablastic rat serum, the parasites do not reproduce but remain as adults. If the medium is inoculated with reproducing trypanosomes from the blood, parasites in the presence of normal serum continue to reproduce, whereas those exposed to ablastin are almost completely converted to adult, non-reproducing forms. Similar results are obtained when the immune sera used are first adsorbed with living parasites to remove all trypanocidal antibodies. Ablastic serum inactivated at 56d̀C for 20 minutes does not lose its inhibitory activity indicating that ablastin is not complement dependent, and parasites grown on media at room temperature are not affected by the antibody suggesting that basic antigenic differences exist between blood stream forms at 37d̀C and culture forms at room temperature. Studies of the conversion of blood stream forms to culture forms indicate that the critical temperature range for the conversion lies between 28d̀ and 30d̀C. The significance of these results is discussed, and possible applications of the techniques described to studies of the mechanism of ablastic action are considered.

Notes: SYNOPSIS. Normal swimming behavior of Paramecium multimicronucleatum in an essential mineral element solution with 0.0002 M calcium changed into continuous avoidance reactions upon replacement by equimolar strontium; equimolar barium produced a less pronounced similar effect. In equivalent pure SrCl2 and BaCl2 solutions, avoidance reactions were less frequent than in the balanced solutions. P. multimicronucleatum inoculated into autoclaved calcium- or strontium-containing cultures of the alga Protosiphon botryoides (ultimate food source) multiplied greatly and essentially equally, but died in barium. Accelerated avoidance reaction rates were observed in strontium up to and at 32 days after inoculation.

Notes: SYNOPSIS. A previous study of parasites from relapsed P. berghei infections of mice indicated that the behavior of the relapse parasites differed from that of their parent strain. Experiments have been performed comparing the behavior of relapse and parent parasite infections in mice under two sets of conditions. In one group of experiments the behavior after antimalarial treatments, designed to result in chronic or latent states of infection, was tested. In all, 8 relapse strains were tested against their parent strains in six different experiments which employed 536 mice. It was observed that the mice infected with the relapse strains had a statistically significant greater mortality after the treatments than did mice infected with parent strains. This difference was observed regardless of how the relapse strain had been previously treated, or of what treatment was used in the experiments. In a second group of experiments, the behavior of infections with relapse and parent parasites was compared in normal mice. Five relapse strains were compared to their parent strains in a total of 5 experiments using 356 mice. It was observed that the mean survival time of mice infected with relapse strains was significantly greater than that of mice infected with the parent strains. It is not known whether this apparent difference in the behavior of relapse and parent parasites is related to the mechanism for relapse of P. berghei infections, or is merely a characteristic of parasites that had survived in an immune host.

Notes: One third of a collection of cloned Stylonychia pustulata micronuclear DNA PstI fragments were found to be of a similar size, consistent with their being members of a repetitious sequence family with a repeat size of about 160 base pairs. Cross-hybridization experiments confirmed that these small cloned fragments are related by sequence homology. Hybridization of the cloned repetitious sequences to PstI digested micronuclear DNA revealed a “ladder” of bands (step size = 160 base pairs), indicating that the repeats are found in tandem arrays. This is the first demonstration of highly repetitious, tandemly repeated sequences in a ciliated protozoan.

Notes: The erythrocytic developmental cycle of Plasmodium falciparum can be conveniently divided into the ring, trophozoite, and schizont stages based on morphology and metabolism. Using highly synchronous cultures of P. falciparum, considerable variation was demonstrated among these stages in sensitivity to chloroquine. The effects of timed, sequential exposure to several clinically relevant concentrations of chloroquine were monitored by three techniques: morphological analysis, changes in the rate of glucose consumption, and changes in the incorporation of 3H-hypoxanthine into parasite nucleic acids. All three techniques gave essentially identical results. The trophozoite and schizont stages were considerably more sensitive to the drug than ring-stage parasites. Chloroquine sensitivity decreased as nuclear division neared completion. The increase in chloroquine sensitivity was coincident with a marked rise in the rate of glucose consumption and nucleic acid synthesis. The rate of nucleic acid synthesis decreased as schizogony progressed while glucose consumption continued at high rates during this process. The degree of chloroquine sensitivity was not highly correlated with either metabolic activity.

Notes: Bloodstream trypomastigote and culture procyclic (insect midgut) forms of a cloned T. rhodesiense variant (WRATat 1) were tested for agglutination with the lectins concanavalin A (Con A), phytohemagglutinin P (PP), soybean agglutinin (SBA), fucose binding protein (FBP), wheat germ agglutinin (WGA), and castor bean lectin (RCA). Fluorescence-microscopic localization of lectin binding to both formalin-fixed trypomastigotes and red cells was determined with fluorescein isothiocyanate (FITC)-conjugated Con A, SBA, FBP, WGA, RCA, PNA (peanut agglutinin), DBA (Dolichos bifloris), and UEA (Ulex europaeus) lectins. Electron microscopic localization of lectin binding sites on bloodstream trypomastigotes was accomplished by the Con A-horseradish peroxidase-diaminobenzidine (HRP-DAB) technique, and by a Con A-biotin/avidin-ferritin method. Trypomastigotes, isolated by centrifugation or filtration through DEAE-cellulose or thawed after cryopreservation, were agglutinated by the lectins Con A and PP with agglutination strength scored as Con A 〈 PP. No agglutination was observed in control preparations or with the lectins WGA, FBA or SBA. Red cells were agglutinated by all the lectins tested. Formalin-fixed bloodstream trypomastigotes bound FITC-Con A and FITC-RCA but not FITC-WGA, -SBA, -PNA, -UEA or -DBA lectins. All FITC-labeled lectins bound to red cells. Con A receptors, visualized by Con A-HRP-DAB and Con A-biotin/avidin-ferritin techniques, were distributed uniformly on T. rhodesiense bloodstream forms. No lectin receptors were visualized on control preparations. Culture procyclics lacked a cell surface coat and were agglutinated by Con A and WGA but not RCA, SBA, PP and FBP. Procyclics were not agglutinated by lectins in the presence of competing sugar at 0.25 M. The expression of lectin binding cell surface saccharides of T. rhodesiense WRATat 1 is related to the parasite stage. Sugars resembling α-D-mannose are on the surface of bloodstream trypomastigotes and culture procyclics; n-acetyl-D-galactosamine and D-galactose residues are on bloodstream forms; and n-acetyl-D-glucosamine-like sugars are on procyclic stages.

Notes: The cationic permeant fluorescent dye rhodamine 123 (R123) was used to stain Plasmodium yoelii-infected mouse erythrocytes. Fluorescence microscopic observations demonstrated that the parasite, but not the matrix of the infected erythrocyte, accumulated the dye. Differences in fluorescence intensity could not be found at the various developmental stages of the parasite; however, quantitation of the cell-associated dye revealed an increase in R123 uptake with parasite development. The retention of the parasite-associated dye, as measured by fluorescence microscopy and spectrophotometry after extraction of R123 with butanol, was markedly reduced by treatment of the infected erythrocytes with a proton ionophore, carbonyl cyanide m-chlorophenylhydrazone (CCCP), and an inhibitor of proton ATPase, dicyclohexylcarbodiimide (DCCD). These results indicate that the accumulation and retention of R123 in P. yoelii reflect the parasite membrane potential and suggest that the parasite plasma membrane has a membrane potential-generating proton pump.

Notes: Distinctive organic-walled resting cysts of at least three different types with a highly conservative morphology appear to characterize specific orders or groups of genera within the Class Polyhymenophorea (Protozoa, Ciliophora), contrasting markedly with the great diversity of form seen in trophic stages. Polyhymenophorean ciliates have been considered in the past to form a cohesive class within the Phylum Ciliophora and, possibly, to represent the pinnacle of ciliate evolution. Evidence from cysts challenges the cohesive nature of the class, suggesting that the hypotrichs should be subdivided and that they have a different phylogenetic origin from the heterotrichs, tintinnids, and oligotrichs.

Notes: Yellow-brown, algal symbionts varying in diameter from approximately 5 μ m to 20 μ m, associated with solitary Radiolaria with spongiose skeletons (i.e. Spongodrymus sp.), exhibit fine structural features resembling the Prymnesiida (botanical class, Prymnesiophyceae). A large central vacuole is surrounded by a thin layer of cytoplasm containing plastids with lamellae composed of three thylakoids and granular pyrenoids with internal tubules immersed between the thylakoids. The pyrenoids lack internal thylakoid membranes. The nucleus is surrounded by a dilated cisterna of the nuclear envelope that also encloses the plastids and gives rise to saccules of the endoplasmic reticulum. The algal symbionts appear coccoid; hence no flagella nor surface scales were observed. The symbiont fine structure is compared to similar yellow-brown symbionts associated with Acantharia. Thus far, three kinds of algal symbionts have been observed to be associated with solitary Radiolaria: dinoflagellate, prasinomonad, and this apparent prymnesiomonad.

Notes: Ultrastructural observations of the cortically-located mitochondria of Tetrahymena thermophila revealed associations not only between the mitochondria and certain of the cortical microtubule bands, but also between the mitochondria and the epiplasm of the cortex. Most of the distal mitochondrial surface is close and parallel to the epiplasm; favorable views show bridge-like structures spanning the 20–10 nm gap between the mitochondrion and the epiplasm.Previous studies have shown that the placement of mitochondria in the cortex appears to be determined by certain of the cortical microtubule bands. This study, however, shows that mitochondrion-microtubule interactions account for only a small proportion of the total mitochondrial area associated with the cortex; the rest is accounted for by the epiplasm. A possible analogue of the spectrin layer of erythrocyte membranes, the epiplasm may be important in helping to arrange the intricately organized components of the ciliate cortex. Its involvement in apparently helping to “moor” mitochondria to their cortical sites is the first suggestion of any role in cell patterning played by the epiplasm.

Notes: Ce Tetradimorpha, rencontre en eau douce se présente soit sous forme sphérique pourvue de quatre flagelles et d'axopodes rayonnants, soit sous forme allongée avec a l'avant quatre flagelles associes a quatre axopodes et a l'arriére six a huit axopodes divergents. L'etude ultrastructurale révèle un cytosquelette axopodial de type centroplastidie comprenant un centroplaste lenticulaire homogéne, centre organisateur des quatre axopodes anterieurs et des six a huit axopodes posterieurs, auquel s'ajoutent les quatre cinetosomes des flagelles anterieurs. En outre, un deuxiéme éleément cytosquelettique incluant un microtubule associe chacun des quatre cinetosomes a l'axopode antérieur correspondant. Des cordons microfibrillaires réunissent axopodes et cinetosomes au niveau du centroplaste, puis a quelque distance du centroplaste les axopodes posterieurs. Les axonémes des axopodes comprenant de 5 a 30 microtubules sont constitues de triades, lorsqu'on peut détecter une organisation. Le noyau, a nucléole central est coince dans le cone axopodial posterieur, lui-méme entouré des dictyosomes. Par l'organisation du cytosquelette, par la structure des kinétocystes, par la structure des flagelles dépourvus de mastigonémes tubulaires, Tetradimorpha différe nettement de Ciliophrys marina. Comme le prévoyait Davidson (1975), il represönte bien un des chainons dans la série évolutive des Héliozoaires centrohélidiens. Mais il ne présente guère d'affinites avec les Chrysomonadines considerees comme la souche des Héliozoaires. L'intéret de ce Protiste dans l'étude de la differentiation et de l'evolution du cytosquelette est également présente.〈section xml:id="abs1-2"〉〈title type="main"〉ABSTRACTThis freshwater species of Tetradimorpha has a spherical body with four flagella and radiating axopods; it transforms into a pear-shaped cell that anteriorly has four flagella intercalated between four axopods and posteriorly has six to eight divergent axopods. Ultrastructural study reveals an axopodial cytoskeleton of the centrohelidan type comprising an homogeneous lenticular centroplast which acts as MTOC for axopodial microtubules. A second skeletal element is a microtubular linkage between the kinetosomes and the axonemes of anterior axopods. A microtubule embedded in dense material diverges from near the base of each kinetosomes and parallels the distal portion of the axoneme of each anterior axopod. A microfibrillar envelope around the centroplast links the axopodial bases to the kinetosomes situated just above. Close to the centroplast, microfibrillar strands link the axopodial axonemes to the kinetosomes. Axopodial axonemes are composed of 5 to 30 microtubules irregularly arranged except for some that form equilateral triangles. The nucleus containing a central nucleolus is constrained within a cone formed by the axonemes of the posterior axopods and surrounded by dictyosomes. By the cytoskeletal organization, the structure of kinetocysts, and flagella wthout tubular mastigonemes, Tetradimorpha differs obviously from Ciliophrys marina. As Davidson (1975) predicted, Tetradimorpha is an intermediate link in the centrohelidan lineage: however, it lacks the characteristics of chrysomonads, the supposed ancestors of Heliozoa. The contribution of this genus to the study of the differentiation and the evolution of the cytoskeleton is also presented and discussed.

Notes: Two-dimensional gel electrophoresis was used to identify the patterns of protein synthesis during initiation, and the patterns of membrane protein expression following initiation, in all of the mating types of the Tetrahymena thermophila B family. In addition, one-dimensional analysis was used to survey 125I-Concanavalin A-binding proteins. Although a large number of proteins was identified by each technique, no variation among the mating types was observed.

Notes: Cells of Tetrahymena pyriformis, T. thermophila, and Euglena gracilis were saturated with nitrogen gas at pressures up to 300 atm and rapidly decompressed. Damage was assessed by measuring post-decompression cell fragmentation or viability. Occurrence of intracellular bubbles was determined by cinephotomicrography performed during the decompression or by direct observations afterwards. The extreme gas supersaturations induced led to intracellular bubble formation and rupture in cells of Tetrahymena that contained food vacuoles, but only with supersaturations of 175 atm or higher; 225 atm left few cells intact. Bubbles were never observed in cells of Euglena or in Tetrahymena cells freed of food vacuoles, even when they were decompressed from substantially higher nitrogen supersaturations. Cells of Euglena were most resistant and were unaffected by supersaturations up to 250 atm.

Notes: The rapid, synchronous differentiation of N. gruberi from amoebae to flagellates is a useful paradigm to study aspects of cell differentiation, including regulation of the synthesis of proteins that are related to the changes in cell shape and motility, which occur during differentiation. The differentiation requires synthesis of new RNA and protein molecules to accomplish defined morphogenetic events. Specific new proteins, including the tubulins that form the flagellar microtubules, are synthesized at various times during differentiation, and particular mRNA species appear and disappear. The time course of the synthesis of the α and β subunits of flagellar tubulin is paralleled by the programmed appearance and disappearance of flagellar tubulin mRNAs. The evidence supports the hypothesis that the synthesis of flagellar tubulin is regulated by the transcription, and subsequent disappearance, of flagellar tubulin mRNA. Translatable mRNAs for two calmodulin-like calcium-binding proteins appear and disappear contemporaneously with those for flagellar tubulin. During differentiation the synthesis of actin, the major protein of amoebae, is selectively shut down, and translatable actin mRNA rapidly disappears. This description of the orderly appearance, utilization, and disappearance of the mRNAs for actin, calcium-binding proteins, and flagellar tubulin during differentiation provides means and motivation to investigate the mechanisms that regulate these events.

Notes: Earlier experimental work involving macronuclear implants in Stentor coeruleus has shown that the cytoplasmic cortex of the nuclear site 1) attracts the macronucleus and 2) holds it in place during interphase. Now experiments indicate macronuclei transferred with overlying cortex elongate in the direction of the transferred cortical pigment stripes, whether or not the transferred stripes realign in the direction of the host stentor's stripes. Therefore the third function of the cortex is to determine the direction of elongation and thus assure that both daughter cells at division receive part of the macronucleus.

Notes: During an electron microscopic study of Glugea stephani, three morphologically distinct tubular appendages that are continuous with the sporoblast plasmalemma were observed. The tubules were designated as: type I, 45–50 nm in diameter and 600–900 nm in length; type II, 25–35 nm in diameter, averaging 1300 nm in length; type III, 50–70 nm in diameter and with an indeterminate length, which often exceeds 3000 nm. Type III tubules contain regularly spaced, electron-dense particles that are approximately 30 nm in diameter. Since many genera of microsporida have some type of appendage, which may eventually be utilized for taxonomic purposes, we propose the formation of a system of serially numbered detailed descriptions of these structures to promote uniformity and clarity in future publications.

Notes: Cells of Paramecium tetraurelia, stock hrd, cultured in a micro-capillary containing 1 μl fresh culture medium, expressed mating activity through the whole cell cycle. Mating-reactive G2 phase cells can conjugate with cells of other phases. The G2 phase cells, which have double (4C) the normal micronuclear DNA content, undergo pre-meiotic DNA synthesis when conjugated with G1 phase cells. The micronucleus of the progeny from the cross between a G1 and a G2 cell becomes triploid.

Notes: Buffered solutions of KCl and NaCl were tested for their stimulatory effect on the germination of variously-aged spores of Vavraia culicis. Germination was optimal in 0.2 M KCl, pH 6.5 for one isolate, and, for another isolate, peaks of germination occurred at pH 7.0 and 9.5. Spores incubated for several hours in suboptimal solutions became unable to germinate under optimal conditions. After being returned to water, they regained their ability to germinate. Calcium chloride, magnesium chloride, and ammonium chloride inhibited germination. After ingestion by mosquito larvae, spores germinated near the posterior end of the midgut.

Notes: . Leishmania tropica promastigotes transport α-aminoisobutyric acid (AIB), the nonmetabolizable analog of neutral amino acids, against a substantial concentration gradient. AIB is not incorporated into cellular material but accumulates within the cells in an unaltered form. Intracellular AIB exchanges with external AIB. Various energy inhibitors (amytal, HOQNO, KCN, DNP, CCCP, and arsenate) and sulfhydryl reagents (NEM, pCMB, and iodoacetate) severely inhibit uptake. The uptake system is saturable with reference to AIB-and the Lineweaver-Burk plots show biphasic kinetics suggesting the involvement of two transport systems. AIB shares a common transport system with alanine, cysteine, glycine, methionine, serine, and proline. Uptake is regulated by feedback inhibition and transinhibition.

Notes: . Oxytricha strains used in biochemical studies have traditionally been grown in unaerated, unagitated culture tubes or Fernbach flasks. These cultures are limited in volume to about one liter and have a very nonuniform distribution of cells, with the majority of the cells at the very top or bottom of the medium. We have found conditions in which Oxytricha can be grown in 50-liter fermentation vats. The cultures grow to a uniform density of about 6000 cells/ml.

Notes: . The fine structure of the tomite of Foettingeria actiniarum (Claparède) was examined and compared with that of other apostome tomites. This stage in the life cycle has a unique configuration of kineties that form a spiral through the cytoplasm in the interior of the body. The structure and behavior of this internal spiral were evaluated as a mechanism for the storage of kinetosomes, an adaptation to the ciliate's two-host life cycle. The spiral is composed of nine ribbons of laterally compressed kinetosomes that are in contact with a thin electron-dense fibril. Paralleling the kineties of the spiral are conspicuous, swollen lamellae of the rough endoplasmic reticulum; these lamellae contain moderately electron-dense material. The spiral is associated with the large contractile vacuole and winds about the macronucleus. The tomite of Foettingeria possesses a single, robust, caudal cilium located in a pit, along with the nozzle-like pore of the contractile vacuole. The walls of the pit contain several trichocysts arranged radially about the caudal cilium and aimed into the pit.

Notes: . Fine structural studies of a specialized vesicle system associated with the endoplasmic reticulum (ER) of exo-erythrocytic Plasmodium berghei suggest that this system may be the equivalent of a Golgi apparatus. Patches of ER, randomly distributed in the cytoplasm of developing parasites, are formed of smooth and ribosome-studded cisternae intermingled with each other. The vesicle systems are located between as well as at the edges of ER aggregates and appear to be in different stages of budding from the cisternae. Prolonged osmication reveals distinct staining of the nuclear envelope and ER of the parasites as well as part of the Golgi apparatus of the hepatocytes. However, the small vesicles associated with the parasite's ER are unstained, as are the coated vesicles in the Golgi region of the liver cell. These sites in the parasite cytoplasm seem comparable to the concave surface of the Golgi apparatus in liver cells. The pinched-off vesicles fuse with others to form the prominent peripheral vacuolization characteristic of the nearly mature exo-erythrocytic form. The formation of these peripheral vacuoles and their subsequent fusion with the parasite membrane may be an exocytosis mechanism supplying the rapidly expanding parasite with new plasma membrane material.

Notes: . Ultrastructural cytochemical techniques were used to analyze the nucleus and the kinetoplast of epimastigotes of Trypanosoma cruzi. With the use of ethanolic phosphotungstic acid, which detects basic proteins, reaction product was seen in the chromatin and at the periphery of the kinetoplast. Thallium alcoholate, which interacts with DNA, stained strongly the whole kinetoplast and the chromatin. With the use of a silver impregnation method that detects acidic nucleolar proteins, silver granules were seen preferentially located in the central region of the nucleolus. With the EDTA method, which reveals the presence of ribonucleoproteins, staining was observed in the nuclear pores. Also 6–8 nm fibrils, 25 nm and 40 nm granules, which correspond to the perichromatin fibers, interchromatin granules and the perichromatin granules, respectively, were identified in the nucleus. The EDTA method also revealed the presence of 40 nm granules in the kinetoplast. These granules were seen mainly at the two extremities of the kinetoplast. Freeze-fracture images indicate that the nuclear membrane contains ca. 9 pores/μm2 of nuclear surface area. The mean diameter of the pores was 80 nm. All these results suggest that epimastigotes of T. cruzi have a very active nucleus and a high rate of nucleocytoplasmic interchange.

Notes: SYNOPSIS. Schizonts were found in the middle and lower third of the small intestine of two calves killed 12 and 14 days after they had been inoculated with pure cultures of oocysts of Eimeria auburnensis. The schizonts ranged from 78 to 250 μ long by 78 to 150 μ wide (mean 92 by 139.9 μ). They were usually located deep in the lamina propria near the muscularis mucosae instead of in the villi where most schizonts of Eimeria bovis are found. The schizonts of E. auburnensis resembled the previously described large microgametocytes of this species but were distinguishable morphologically and by histochemical stains. The microgametocytes were much larger than previously reported; one measured 91 by 287.5 μ.

Notes: SYNOPSIS. Three new species of Blepharisma are presented: B. seshachari sp. nov., B. intermedium sp. nov., and B. tropicum sp. nov. Two sub-species of Suzuki are elevated to specific rank, B. undulans americanum to B. americanum and B. undulans japonicum Suzuki to B. japonicum Suzuki. Stein's taxa for the species Blepharisma undulans are considered to be diagnostic for that species.Important features of morphology and life-cycle of the above mentioned species are given. Discussion and position of the species Blepharisma undulans are presented and a proposal for the reorganization of the species is made. The possibility of a new key derived from a hypothesis of the phylogeny on an evolutionary basis of the genus is presented. This hypothesis has been extended to include ciliates like Stentor and Spirostomum and its implications discussed.

Notes: SYNOPSIS. A laboratory colony of Oncopeltus fasciatus was found to be infected with Leptomonas oncopelti. Inasmuch as the parasite is transmitted from parent to offspring an opportunity presented itself to study the biology and transmission of this parasite under controlled laboratory conditions. An apparatus for observing individual bugs was designed and the presence or absence of flagellates in the feces determined. Flagellates were not shed until the bugs became adults after which they appeared in every defecation. Dissection of infected bugs revealed that flagellates were not present in the rectum until adulthood. Further studies indicated that in the midgut of the insect there is a departure from binary fission to budding. The nucleus divides and one of the newly formed nuclei migrates toward a newly formed kinetoplast. Rarely there is still another kinetoplast/nucleus division. In the event the new axoneme grows within the cytoplasmic sheath of the parent flagellum, smaller organisms produced by unequal cytokinesis remain attached. If the axoneme grows free, the smaller daughter organisms become free-swimming. Passage into the rectum of the adult bugs causes a rounding up of all parasites although the leishmaniform organisms continue to divide. It is presumed that infection of clean bugs is accomplished by the ingestion of leishmaniform organisms through a common water source. The reason for the presence of flagellates in the rectum of the adult but not in the nymphal insect and the mechanism responsible for the change from binary to unequal fission are not known.

Notes: SYNOPSIS. Examination of intestinal contents and feces of Wisconsin red squirrels (Tamiasciurus hudsonicus) revealed two coccidia, Eimeria tamiasciuri and E. toddi n.sp. In the Eastern chipmunk (Tamias striatus), two species, E. vilasi n.sp. and E. wisconsinensis n.sp. occurred. In the northern flying squirrel (Glaucomys sabrinus), a coccidium resembling E. sciurorum was found.

Notes: SYNOPSIS. A large heterotrich ciliate (Family: Bursariidae) found in a papyrus swamp in Uganda was used for oxygen tension experiments by Beadle & Nilsson, 1959, under the name of Bursaria sp. This organism has now been identified as Neobursaridium gigas Balech. The morphology of the organism was studied in living and stained specimens, especially with the silver impregnation technique, and the present findings are compared to those of Balech.

Notes: SYNOPSIS. An electron microscope study of thin sections of Babesia rodhaini parasitizing mouse erythrocytes showed that this intracellular parasite feeds on its host cell in the same way as do malarial parasites. Large portions of erythrocyte cytoplasm are engulfed by invaginations of the plasma membrane leading to the formation of food vacuoles. The digestion of hemoglobin seems to be complete in Babesia since no pigment (hemozoin) could be detected either in the food vacuoles or in the cytoplasm.The fine structure of Babesia rodhaini is very similar to that of Plasmodium berghei. In both, typical mitochondria are lacking. Instead a structure was found composed of concentric membranes which it is assumed might perform mitochondrial functions. As in Plasmodium berghei a double-membraned vacuole with a matrix of low density is present in almost all sections. The endoplasmic reticulum is represented by small vesicles; the ground-substance is filled with Palade's small particles. The nucleus is large and surrounded by two membranes. Babesia reproduces by budding and binary fission. Reproduction is not easy to identify since the parasite forms large pseudopods resembling stages in division.

Notes: SYNOPSIS. The effect of 10 detergents on the inhibitory activity of neomycin was tested against Ochromonas danica. All 4 anionic detergents used were synergistic with neomycin. Evidence is presented that the synergisms were due to the effect of the detergents on the cell membrane. In the presence of Tergitol 7, O. danica is more susceptible to changes in osmotic pressure by increasing concentrations of KCl.

Notes: SYNOPSIS. All zoologists are affected by provisions in the very recently published International Code of Zoological Nomenclature, the first revised edition of these important rules to appear in over 50 years. Common nomenclatural practices, often malpractices, of protozoologists and parasitologists who work primarily in taxonomic fields are revealed and discussed in light of recommendations and mandatory regulations to be found in the new Code. Some errors have been due solely to carelessness; others have involved misinterpretations of various directives; still others have involved cases not adequately covered by the old Règles. Certain mistakes of the past cannot be changed; but others are to be rectified upon discovery, according to mandates in articles of the new Code. Practical applications of the rules of nomenclature are stressed, and examples are taken from actual situations found to exist throughout all major taxa of the phylum Protozoa.Because of the value of such discussion in both new and revisory work in protozoan systematics, the following major topics are given special consideration: matters of orthography, the original spelling of names and their justified or unjustified emendation; authorships and dates of names, who is responsible and when, and how such data are properly cited; mandatory dates in the new Code, and their effect on both already established names and names not yet proposed; the principles of priority and conservation or continuity, and how the rules attempt to satisfy proponents of both of these diametrically opposed “laws”; the concepts of synonymy and homonymy, and proper methods of treating names which have become involved in such situations; family-group names, and the several special nomenclatural problems they present to protozoan taxonomists; the major problem of types, and the peculiar position of protozoologists with regard to the type concept, especially type-specimens for categories in the species-group; miscellaneous considerations, several unrelated but significant topics not appropriate for inclusion in preceding sections of the paper.

Notes: SYNOPSIS. In a chemically-defined medium Tetrahymena setifera HZ-1 required a sterol, an alcohol, eleven amino acids, a purine, a pyrimidine, and six B-complex vitamins. The sterol requirement was met by a variety of 3β-OH, C27-C29 sterols including cholesterol and stigmasterol, but not by precursors of cholesterol which precede desmosterol or Δ7-cholestenol. Some combinations of long-chain fatty acids with a synthetic dipalmitoyl phosphorylethanolamine partly substituted for sterol. Ethyl and methyl alcohols (but not a variety of other alcohols and organic acids) satisfied the alcohol requirement.

Notes: SYNOPSIS. Trichomonas vaginalis grown aerobically slowly metabolizes glucose-U-C14 and succinate-2,3-C14 to CO2 and to amino acids which are then incorporated into protein. Analysis of protein hydrolysates from cells grown on glucose-U-C14 reveals radioactivity in 15 amino acids. Although the data do not permit a direct interpretation and analysis of the sequence of amino acid biosynthesis, it seems likely that a tricarboxylic acid cycle operates. Attempts to prepare cell-free systems carrying out cycle reactions have proved unsuccessful.

Notes: SYNOPSIS. One hundred eighty-eight fresh-water samples from France (30), Italy (42), Austria (12), Germany (1), Switzerland (35), Holland (20), England (26), and Sweden (22) were examined for T. pyriformis. The habitats included rivers, mountain streams, lakes, ponds, irrigation ditches, roadside ditches, running and dead water canals, and fountains. The temperature ranged from 10° to 30°C, locations from 42° to 68° North latitude, with elevations from sea level to approximately 3,000 feet. Of the samples taken 28 contained T. pyriformis from which 411 clones were established in axenic media. Thirty-three additional samples contained ciliates other than T. pyriformis. All clones grew well in 1% proteose peptone; when screened for their nutritional requirements a few failed to grow on the completely defined medium and several others survived eight sub-inoculations without thiamine.The nuclear and sexual activity pattern followed that of previous collections. In distribution, variety 6 was found in Italy, variety 3 in Austria, and variety 4 in England. A new variety (variety 10) with two mating types was isolated from four different habitats in England. Several strains from Italy, France, Holland, and England constitute one group which mated among themselves, but only a few of which reacted with mating type I of variety 6 from America. This demonstrates the close affinities of the European and American strains, yet shows the possible evolution of a new variety (species).

Notes: SYNOPSIS. The steroid requirement of a Trypticase-requiring strain, SLT, of Trichomonas gallinae on the Shorb-Lund synthetic basal medium minus ribonucleic acid was fulfilled by cholesterol, 7-dehydrocholesterol(provitamin D3), cholestanol (dihydrocholesterol), and to a lesser degree, by ergosterol (provitamin D2), β-sitosterol and zymosterol acetate. Cholestanol was inhibitory at certain concentrations. All steroids were subsequently checked by gas chromatography. Only cholesterol and zymosterol acetate showed one peak, the others containing 2 to 4 peaks. Repurified cholestanol was active and showed no inhibition of growth, but repurified β-sitosterol was inactive. The following were also inactive: diethylstilbestrol, estrone, dehydroepiandrosterone, progesterone, testosterone, desoxycorticosterone acetate, cortisone acetate, compound A, 5,6-dihydro-ergosterol, dihydroergosterol acetate, stigmasterol, sodium taurocholate, cholic acid, methyl desoxycholate, desoxycholic acid and methyl cholate. Precursors in cholesterol synthesis, acetate, mevalonic acid, mevalonic acid plus a liver extract and squalene were inactive in replacing cholesterol, although acetate is required for growth in the presence of cholesterol. Crystalline fat soluble vitamins, carotene, calciferol (vitamin D2), activated 7-dehydrocholesterol (vitamin D3), menadione (vitamin K3) and tocopheryl acetate (vitamin E acetate) were inactive in replacing cholesterol. Trichomonas species PN from the pig's nose utilized cholesterol, 7-dehydrocholesterol and the impure β-sitosterol sample in a modified SL medium with acetate omitted. A reinvestigation of steroid requirements seems to be indicated when a completely synthetic medium and pure steroids are available.

Notes: SYNOPSIS. Protoplasm transferred to a multinucleated amoeba is well tolerated if the donor and recipient portions are from the same amoeba, from different amoebae of a single clone, from different amoebae of the same species found in a given location, or from different amoebae of the same species found in widely separated geographic areas. On the other hand, protoplasm is not tolerated and death invariably follows interspecific or intergeneric microtransfers between any two of the three species of amoebae used in this study.Attempts to overcome the tolerance block in heterologous transfers by the use of x-radiation failed although a significant extension of the mean survival time was obtained. The latter can also be interpreted as a limited therapeutic effect of nonirradiated, heterologous donor protoplasm on supralethally irradiated recipients.

Notes: SYNOPSIS. Cultures of Prymnesium parvum subjected to constant illumination failed to produce ichthyotoxin. On the other hand cultures subjected to alternate periods of light and darkness showed a gradually rising ichthyotoxic activity during the dark period reaching a maximum after about 7 hours.

Notes: SYNOPSIS. A new species, Crithidia rileyi (Trypanosomatidae), is described from Tabanus epistates. The most characteristic feature of the flagellate is the frequent occurrence of a broad sucker-like posterior end. In contrast to other species of Crithidia it multiplied very slowly in the first few weeks after isolation. A review of the literature shows that trypanosomatids of two generic types, Crithidia and Blastocrithidia, have been described from flies of the family Tabanidae, although they have nearly always been regarded as stages of the same organism. Some or all of those of the Blastocrithidia type are stages of Trypanosoma theileri. The Crithidia are probably not stages in the development of any trypanosome.

Notes: SYNOPSIS. Gromia oviformis from New Zealand has been examined in thin sections after fixing in osmium tetroxide and embedding in methacrylate. The structure of the protein and acid mucopolysaccharide shell and the canals which pass radially through it are described. Multiple honeycomb membranes located between the shell and the cytoplasm, as well as mitochondria and “Golgi bodies,” none of which has hitherto been seen in light microscope studies, are discussed and illustrated. The previously known stercomata and xanthosomes are considered. Though still regarded as enigmatic cytoplasmic inclusions, observations suggest that they are waste products retained within the animal throughout life.

Notes: SYNOPSIS. An agar overlay technique developed to investigate the effect of various substances on growth of a selected group of protozoa is described. Test systems employing Crithidia fasciculata (culex), Ochromonas malhamensis, Tetrahymena pyriformis W and Trichomonas foetus were devised to evaluate the effect of known compounds and to assay the activity of antibiotic fermentation beers. This disc-plate method can be summarized as follows: preparation of a foundation layer; overlaying of a mixture of agar, nutrients, protective antibiotics, and inoculum; placing of paper discs with the test material on the overlay followed by incubation and subsequent observation of the plates for zones of inhibition of growth. The concentration of agar in the overlay sufficient to restrict movement of the protozoa without inhibiting their growth, nutrients required for adequate growth and continued viability of the inoculum, and the concentration of penicillin and streptomycin which will not inhibit the assay protozoa but beeffective against the microorganisms in the fermentation beers are discussed. This technique offers a method not only for primary screening for cytotoxic substances but also one which may be adaptable to other studies of protozoa.

Notes: SYNOPSIS. Acid phosphatase activity was studied in total mounts and sections of agnotobiotic Paramecium multimicronucleatum by the alpha-naphthyl phosphate-hexazotized rosanilin method. Timing was achieved by India ink marking of food vacuoles. Enzyme activity is present in small endoplasmic granules and in the greatest part of food vacuoles. Following an inactive stage (stage I) of an average length of 5 min the activity appears at the periphery of the vacuole, in most cases in the form of granules (stage II). A high activity level (stage III) is attained within 1 1/2 min and maintained for the most part of the vacuolar cycle. The activity disappears only in the latest vacuoles before egestion (stage IV). The appearance of activity is not concurrent with but succeeding to the maximum of vacuolar acidity as ascertained by feeding Congo red stained killed yeast cells. On the basis of these results the food vacuoles may be looked upon as belonging to the lysosomes sensu lato.

Notes: SYNOPSIS. In Oxytricha fallax, extrusion of all the excretory crystals and some refractile bodies occurs when food is with held. The precystic animals thus resulting become transparent and undergo dedifferentiation of organelles. First the undulating membrane and cytostome are entirely resorbed, producing astomial forms. Then the adoral membranelles vanish gradually, accompanying which the somatic ciliature such as the cirri comes to be resorbed. Occasionally, early precystic animals retaining the intact feeding organelles reorganize spontaneously (physiological regeneration), but they become irreversibly encystable by high-temperature treatment; for hastening resorption of feeding organelles accelerates encystment.When transparent animals at various precystic stages are cut in half the posterior fragment (PF) always encysts faster than the anterior one (AF) from the same parent, except that some of the AFs from early stages reorganize into normal vegetative forms. The time difference for completion of encystment between an AF and PF pair is at early stages larger than at later ones. If the anterior part of AF is further excised, the time difference for encystment between AF and PF from the same source becomes smaller or indistinguishable, with the exception that some AFs from early stages regenerate instead. Further, when the anterior part of whole precystic animals is removed, the time for their encystment is reduced. Also in this case, the fragments from early stages normally regenerate.From these results, it is presumed that the adoral membranelles tend to inhibit the encystment process as they do the initiation of an oral primordium in dividers and regenerants of Stentor and other ciliates. Accordingly, when resorption of membranelles becomes extensive as precystic processes progress, their dominance over and inhibition of cyst formation may be diminishing. From the fact that regeneration of fragments from early stages into normal forms may be due to retention of the undulating membrane, its resorption is considered to be an essential prerequisite for the initiation of irreversible encystment.

Notes: SYNOPSIS. A partially purified hexokinase extracted from Euglena had the following properties: 1) pH optimum 8.0–8.5; 2) an absolute requirement for Mg++ and adenosine triphosphate with Mn++, Co++, Zn++, and Ca++ less active or inactive under the test conditions. Inosine triphosphate could not be substituted for adenosine triphosphate; 3) an apparent Km (glucose) of 5 × 10−4 M; 4) the enzyme was not inhibited by the usual sulfhydryl agents, but was inhibited 24% by adenosine diphosphate. The extract phosphorylated fructose and mannose. It was not clear whether a separate enzyme phosphorylated fructose. Relative rates of phosphorylation, as determined by labile phosphate analyses, were: glucose, 1.00; fructose, 1.19; mannose, 0.56. The partially purified extract also contained phosphohexose isomerase activity; 6-phosphogluconic acid dehydrogenase was absent. Euglena hexokinase is apparently localized in the cytoplasmic or small-particle fraction of the cell. In most respects the enzyme seems to resemble the well-characterized yeast hexokinase rather than the muscle enzyme.

Notes: SYNOPSIS. Lankesterella bufonis sp. nov., from toads, Bufo regularis Reuss, in Egypt, described herein, appears to be the first species of this genus to be found in Bufo. Sporozoites of the parasite in circulating blood are usually intracorpuscular, rarely free. Free forms, abundant in smears of internal organs, particularly from lungs, are small, slender, slightly curved bodies with the anterior end more pointed than the other. The small, oval, delicate nucleus is always situated in the posterior third of the parasite, either terminal or more usually subterminal. A single cytoplasmic vacuole is located just anterior of the nucleus and more-or-less centrally. Few darkly stained granules are sometimes seen around the vacuole. Though intracorpuscular forms retain morphological characteristics of the free forms, they frequently undergo peculiar changes: apparently flattening of host-cells during smearing and fixation results in shorter and wider, and sometimes greater width of the parasite. Multiple infection with two and rarely three Lankesterella sporozoites is not uncommon. In liver and spleen smears, certain large cells, apparently of the macrophage or endothelial types, contain forms similar to those described in the peripheral blood, but mostly shorter and broader. Various developmental stages of schizonts were also seen in the liver and lung. In liver, lung, spleen, and kidney sections, numerous young forms, possibly merozoites, were scattered among tissue cells. The present parasite differs morphologically from Lankesterella minima (Chaussat, 1850), L. monilis Labbé, (1894), and L. canadensis Fantham et al., 1942.

Notes: SYNOPSIS. Ophryoglena mugardi is an Ophryoglena of medium size characterized by its spindle-shaped and bimicronuclear theront, by its rather bulky trophont and by its physiological reproductive cycle. During starvation its physiological evolution causes a secondary and temporary encystment of the theront lasting 6 or 7 days (at 18°C). The ultimate re-encystment leads to cytolysis. Feeding induces the physiological reproductive cycle; if food is given soon after the release of the tomites, it determines a primary cycle, usually allowing eight tomites; if it is dispensed only after the secondary encystment of the hungry theront and after its excystment it causes the appearance of secondary cycles, allowing two or four tomites.When the starved theront, becoming smaller and smaller, is fed it produces trophonts which encyst. These no longer divide; each one delivers one theront only. These theronts, smaller and smaller, are able to produce the original major forms, but only after several successive alimental cycles and without any secondary encystment of the theront.

Notes: SYNOPSIS. The plastid system of “normal”Euglena gracilis strain Z was found to be extremely unstable. Under normal culture conditions in the light about 1 or 2% of the cells were found to have lost spontaneously the capacity to green on further culturing. Cells treated with streptomycin, heat or U.V. all lost the capacity to green on further culturing. Bleached cells whether appearing spontaneously or by induction with streptomycin, heat, or U.V. light, were all found to possess within them organelles which were identified as proplastids.The proplastids of some “bleached” strains were capable of synthesizing porphyrins when grown in a standard culture medium. Others synthesized porphyrins only after the addition of delta-aminolevulinic acid to their medium, while proplastids of still other strains could not synthesize porphyrins from this precursor. Normal cells when grown in total darkness were found to possess proplastids morphologically identical with those of the bleached strains. Upon exposure to light the proplastids enlarged and greened. In cells which grew under continuous light the plastid system appeared as an interconnected system of tubules. Cells maintained on a schedule of 12-hour light and 12-hour dark had plastids which were detached from each other.

Notes: SYNOPSIS. Euglena and Chlamydomonas were cultured in an organic medium in the dark and at several light intensities (15, 60 and 150 ft-c) at temperatures from 20d̀ to 35d̀C. Below 32.5d̀, growth of Euglena was independent of light. Chlamydomonas was light dependent at all temperatures where growth occurred; there was no growth in the dark, at 15 ft-c, or at temperatures above 32.5d̀. At 35d̀, growth of Euglena became inversely light dependent; the higher the illumination, the poorer the growth. Multinucleated, giant euglenas were found at 35d̀, a greater percent of abnormal cells appearing at the higher light intensities. Monsters were not observed in Chlamydomonas.To explain the growth-inhibiting, monster-inducing effect of elevated temperatures on Euglena, it is postulated that a dark-formed thermosensitive protein, essential for normal cell division, is denatured. Light may increase the effect of heat on chlorophyll and the chloroplast, possibly by being converted to intraplastidic heat through the plastid carotenoids, thus having some indirect synergistic role in the phenomenon.