These characteristics were correlated with the type of exine ultrastructure, which may be caveate (helianthoid and senecioid types) or non-caveate (anthemoid and arctoid types). According to the ...

Figure 1 - Calea serrata Less., Asteraceae. A. Aspect of aerial vegetative and reproductive organs. B. Abaxial side of the epidermis, in surface view, revealing anticlinal epidermal cell walls and ...