1911 Encyclopædia Britannica/Algae/Polymorphism
its allies, nor is it known in the whole of the Phaeophyceae and Rhodophyceae. In certain Euphaeophyceae bodies built up of concentric layers, and attached to the chromatophores, were described by Schmitz as phaeophycean-starch; they do not, however, give the ordinary starch reaction. Other granules, easily mistaken for the “starch” granules, are also found in the cells of Phaeophyceae; these possess a power of movement apart from the protoplasm, and are considered to be visicles and to contain phloroglucin. The colourless granules of Florideae, which are supposed to constitute the carbohydrate reserve material, have been called floridean-starch. A white efflorescence which appears on certain Brown Algae (Saccorhiza bulbosa, Laminaria saccharina), when they are dried in the air, is found to consist of mannite. Mucin is known in the cell-sap of Acetabularia. Some Siphonales (Codium) give rise to proteid crystalloids, and they are of constant occurrence among Florideae. The presence of tannin has been established in the case of a great number of freshwater algae.