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Notes: SYNOPSIS. Bacteria were required for the sustained reproduction of 4 species of foraminifera in gnotobiotic culture. None of the species of algae tested, singly or in combination, supported continuous reproduction of the foraminifera in bacteria-free gnotobiotic culture. It is inferred that bacteria have some nutritional factor required by the foraminifera that is either unavailable or unavailable in sufficient quantity in an exclusively algal diet.Gnotobiotic clones of Quinqueloculina lata, Spiroloculina hyalina, Rosalina leei, and Allogromia laticollaris were established on bacteria + algae (usually 1 or 2 species). In balanced gnotobiotic cultures neither light nor foraminiferan density (organisms/ml) were limiting. As cultures aged, pH shifted and limited growth. When waste products were removed by washing, reproductive rates were higher.

Notes: Résumé. L'absorption initiale et la migration du 14G-métobromuron se produisirent avec une vitesse identique dans Sinapis arvensis L. et Veronica persica Poir., mais, avec un traitement plus prolongé, [‘accumulation par unité de surface foliaire fut plus importante chez Veronica persica. II n'y eut pas d'accumulation ultérieure dans les racinrs, les tiges, les pétioles ou les nervures foliaires principales des deux espèces après le début de diminution de la radioactivité. II y eut toutefois une accumulation continue sur le bord des feuilles. Aucune relation ne peut être êtablie entre l'absorption et la migration d'une part, et les différences de sensibilityé des deux especes vis-i-vis du mitobromuron d'autre part.L'absorption et la migration du 14C-métobromuron apparurent légèment plusrapides chez Solanum tuberosum, variété Isola que chez la variété Delos. Ceite différence disparut rapidement et la concentration finale par unité de surface fut plus élevée chez Delos que chez Isola. L'accumulation de métobromuron dans les racines, les tiges, les petioles el les nervures des feuilles cessa lorsqu'une concentration particulièere fut alteinte. Dans les portions du limbc entre les nerures et au bord des feuilles, l'accumulation of poursuivit durant toutc I'expérience. Aucune relation ne peut être e'tablie entre l'absorption et la migration d'une part et la sensibilité des deux cultivars d'autre part.Les autoradiogrammes montrèrent que, dans les expériences où le 14C-metoéromuron fut applique sur les racines et sur les feuilles de Sinapis arvensis, de Veronica persica et des deux variétés de pomnies de terre, le métobromuron est, dans des conditions normales, ohligatoirement transporté dans le xylème.Summary. Initial uptake and transport of 14C-metobromuron occurred equally rapidly in Sinapis arvensis L. and Veronica persica Poir., but with longer treatment, accumulation per unit leaf area was greater in V. persica. There was no further accumulation in the roots, stems, petioles or main leaf veins of either species after the initial increase in radioactivity. There was, however, continued accumulation in the leaf margins. No relation was found between uptake and translocation and the differential susceptibility of the two species to metobromuron.Uptake and translocation of 14C-metobromuron was rather more rapid in Solanum tuberosum L. cv. Isola than in cv. Delos. This difference soon disappeared and the final content per unit leaf area was greater in cv. Delos than in cv. Isola. Accumulation of metobromuron in the roots, stems, petioles and leaf veins ceased when a particular concentration had been reached; in the interveinal areas of the legal margins accumulation continued throughout the experiment period. No relation was found between uptake and translocation and the differential susceptibility of the two cultivars.Evaluation of the autoradiograms from experiments with root- and leaf-applied 14C-metobromuron in Sinapis arvensis, Veronica persica and the two potato varieties indicated that under normal conditions metobromuron is obligatorily translocated in the xylem.

Notes: Abstract During the summers of 1966 and 1967, 12 field trips were made to stations in North Sea Harbor, Southampton, Long Island (USA). From representative locations, 228 small samples of larger algae and their epiphytes (∼0.2 g dry weight) were taken aseptically. Enteromorpha intestinalis, the most widely distributed aquatic plant, was the most frequently collected. The large standing crop of Zostera marina and Zanichellia palustris was also sampled. Foraminifera were most abundant in epiphytic communities of Enteromorpha in early summer and later spread to Zostera, Zanichellia, Ulva, Polysiphonia, and Ceramium. Foraminifera were rarely found in epiphytic communities of Fucus or Codium. By summers' end Enteromorpha rarely had a standing crop of foraminifera. One of the most abundant foraminiferan species, Protelphidium tisburyensis, was found most frequently on Enteromorpha; Quinqueloculina spp occurring on Enteromorpha, less frequently. Ammonia beccarri and Elphidium spp were abundant in the environment, and showed little substrate preference. Patches of decaying Enteromorpha had the greatest standing crop of foraminifera and low species diversity index (0.581). Young green patches had a much higher species diversity index (0.94). Indices for Zostera, Zanichellia, Polysiphonia, Fucus, Ulva and Codium were, respectively, 0.82, 0.99, 0.86, 0.70, 0.77, and 0.196. No correlation was found between epiphytic community weight and total number of foraminifera recovered. The standing crop of epiphytes/g substrate dry weight was lower at some field stations; possibly explained by stronger current. Of the total samples, 50.4% were positive, with an average of 18 foraminifera/sample, or 40 foraminifera/g substrate plant and epiphytes. Twenty six samples were classified as bloom with 50 or more forams (57 to 425)/sample. Species diversity indices for these blooms ranged from 0.38 to 1.12. Ammonia beccarii was the dominant form in 18 blooms, Allogromia laticollaris and Protelphidium tisburyensis in 3; Elphidium incertum, Quinqueloculina seminulum and Trochammina inflata in 1 each.