The cryptomonads are a groups of eukaryotic organisms found in fresh and marine waters (Figure 1). They have some features characteristic of protozoa but also have chloroplasts which contain biliprotein, chlorophyll c2 and chlorophyll a. The chloroplasts have thylakoids (Figures 2 and 3) that do not exhibit phycobilisomes on their outer membrane surfaces when examined by electron microscopy. 1-3 Wehrmeyer2 observed that there was a dense granular material in the intrathylakoidal space. Dodge1 also observed this material and suggested that it should be tested to determine if it was the biliproteins.