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To develop an easy and rapid method of quantifying lipid contents of marine dinoflagellates, we quantified lipid contents of common dinoflagellate species using a colorimetric method based on the sulpho-phospho-vanillin reaction. In this method, the optical density measured using a spectrophotometer was significantly positively correlated with the known lipid content of a standard oil (Canola oil). When using this method, the lipid content of each of the dinoflagel-lates Alexandrium minutum, Prorocentrum micans, P. minimum, and Lingulodinium polyedrum was also significantly positively correlated with the optical density and equivalent intensity of color. Thus, when comparing the color intensity or the optical density of a sample of a microalgal species with known color intensities or optical density, the lipid content of the target species could be rapidly quantified. Furthermore, the results of the sensitivity tests showed that only 1-3 × 10 5 cells of P. minimum and A. minutum, 10 4 cells of P. micans, and 10 3 cells of L. polyedrum (approximately 1-5 mL of dense cultures) were needed to determine the lipid content per cell. When the lipid content per cell of 9 dinoflagellates, a dia-tom, and a chlorophyte was analyzed using this method, the lipid content per cell of these microalgae, with the exception of the diatom, were significantly positively correlated with cell size, however, volume specific lipid content per cell was negatively correlated with cell size. Thus, this sulpho-phospho-vanillin method is an easy and rapid method of quantifying the lipid content of autotrophic, mixotrophic, and heterotrophic dinoflagellate species.

Judges were required to rate the total intensity of NaCl solutions using a variety of unstructured category and line scales under a ‘rank‐rating’ protocol and a traditional protocol that did not allow retasting or the reviewing of scores. The various scales and protocols induced two types of scaling errors. The first type was named a different‐stimulus error. This involved a judge rating a stronger stimulus as equal to or less than a weaker stimulus. The second type was named a same‐stimulus error. This involved a judge giving different ratings to two stimuli of equal concentration. For all scales, judges made a higher proportion of same‐stimulus errors than different‐stimulus errors. ‘Rank‐rating’ only reduced the proportion of different‐stimulus errors. It was hypothesized that a category scale with fewer categories would induce a higher level of different‐stimulus errors but lower level of same‐stimulus errors. These trends were noted but not always significantly. For line scales, the equivalent hypotheses regarding line length were either weak or not supported. It would appear that increasing the length of a line scale is not always equivalent to increasing the number of categories in a category scale.

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