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Thirty-one species of multicellular, freshwater red algae exhibited a localized reaction to alcian blue, particularly in mucilaginous layers, rhizoids, nodes, spores and spermatia. The effect of MgCl2 on staining was taxon specific; this may be of value for phylogenetic considerations. Alcian blue was also useful for morphometric analysis of large, complex carposporophytes.
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Sheath et al. (1990) studied this question.
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