Abstract
The spherical cytoplasmic granules of Hydrodictyon reticulatum of 0.5-1.0μ in diameter were stained by Nile blue and showed an intense fluorescence when excited by long wave length ultraviolet light. When these granules were stained with berberine sulfate and excited, they did not show any fluorescence. Therefore, these granules are different from the so-called spherosomes of Perrier since they showed no fluorescence after staining with berberine sulfate. The ground substance of the cytoplasm showed an intense yellow fluorescence after staining with berberine sulfate. Differential centrifugation showed that this fluorescence of the cytoplasm is emitted from the microsomes. In this study, spherical cytoplasmic granules as well as microsomes were distinguished from other cell inclusions by fluorescence analysis with these two dyes.
