No abstract

The salts were added to 75.0 ml. of glass-distilled water, boiled and then cooled slightly. The pH was adjusted to ca. 6.5 by the addition of solid KOH pellets (since the iron precipitates at pH 7.0). The resulting solution was then diluted to 100.0 ml. by the addition of glass-distilled water.

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Nodularia Mertens ex Bornet & Flahault originally established in 1822, has had a total of 28 taxa described. It is restricted in distribution primarily to brackish coastal waters and inland lakes and ponds. In British Columbia (Canada) these lakes and ponds have extreme ranges of salinity (4–400‰) and temperature (0–35 °C). Laboratory studies of 16 isolates indicated maximum growth at 5–10‰, salinity (range 1–60‰), 25–30 °C, pH 10.0–10.5 (range 7.0–10.5) at light intensity of 6000 lx. No preference was shown for dominant anions (Na+, Mg2+) or cations (Cl−, CO32−, S42−). Sheath and akinete characteristics were variable, whereas vegetative cell shape, heterocyst location, and akinete formation were more stable. Investigation of field-collected material, laboratory-grown cultures, and study of herbarium specimens indicate that all the described taxa belong to either N. harveyana [Thwaites] Thuret ex Bornet & Flahault 1886 or N. spumigena Mertens ex Bornet & Flahault 1886. The latter is named the syntype and lectotype material is designated.

Samples of 'red snow' occurring in shaded areas in Mt. Seymour Park, British Columbia, were studied in the field and laboratory. The dominant alga is the volvocalean form Sphaerellopsis rubra nov. sp. The light- and temperature-sensitive organism has been observed in living collections and attempts to culture it have been unsuccessful. The habitat of the new taxon is discussed as well as its relation to the ubiquitous 'red snow alga', Chlamydomonas nivalis.

The algae and fungi occurring in snowbanks in the Front Range of the Colorado Rocky Mountains are described and discussed. Whenever possible, details of the life cycle are given and correlated with reports in the literature. The effect of light on presence of carotenoid pigments is discussed for several species. The following organisms are reported: Carteria nivale; Chlamydomonas nivalis, Chlamydomonas spp.; Chodatella brevispina, Chodatella granulosa; Scotiella cryophila, S. nivalis, S. polyptera; Koliella nivalis; Rhizophydium sp.; Chionaster nivalis.

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The phototoxicity of polyacetylenes from representatives of the Asteraceae to a broad range of freshwater and marine algal species was observed. In the tests triacetylenes were more toxic than diacetylenes. In addition, a small group of polyacetylenes with terminal alcohol or aldehyde groups were found to be toxic with or without ultraviolet (UV) treatment (300–400 nm). Quantitative tests with Euglena and Valonia indicated toxic reactions with three compounds at concentrations greater than 1 ppm. Considering the toxicity of polyacetylenes to bacteria, fungi, invertebrates, and fish, the present work with plants is further evidence of their general cytotoxic nature.