Hauling field gear up Gothic Mountain…
ABSTRACT Cells of the genusColaciumEhrenberg can be distinguished with the light microscope from cells of the genusEuglenaEhrenberg by the presence of basophilic granules in the anterior tip of theColaciumcell which are clustered around the canal opening. The granules exhibit a biphasic pattern of osmiophilia in electron micrographs. Together with the occasionally obscure character of the paramyloncapped, inner pyrenoids, the granules should serve as a useful character to distinguish between the motile, flagellated cells of the two genera whether from laboratory cultures or from field collections of natural populations.