Crystalline bodies in an algal chloroplast

Crystalline inclusions are reported for the first time in the chloroplast of an alga. The cryophilic chlorophycean alga, isolated from snow, lacks a pyrenoid and is tentatively identified as a species of Chlamydomonas. The inclusions are similar to those reported in higher plants and are more abundant in material grown at the optimum temperature of 5 °C. The possibility of a proteinaceous nature of the inclusions is briefly discussed.