Comparative Morphology of the Canellaceae. III. Pollen

Pollen grains of 12 species of the Canellaceae were examined after treatment with KOH-acetolysis or lactic acid. Morphologically the pollen grains in this family are quite uniform--medium-sized, monosulcate with a well-defined furrow, and with a psilate to reticulate exine. Trichotomosulcate pollen grains were found in four of the six genera. The trichotomosulcate pollen grain is interpreted as representing an evolutionary stage between the monosulcate pollen grain and the tricolpate one which is typical of the angiosperms. In confirmation of previous studies the morphological characteristics of the pollen grains of the Canellaceae indicate a relationship with the woody Ranales.