The plant is characterised by its spherical pollen grains, which are typical in the Asteraceae family, a fibrous layer on anthers, lignified, elongated, hypodermal sclerids, and clusters of calcium oxalate crystals.
22.
A few sections of the genus have evolved a novel type of fruit where the seed is embedded in the receptacle material of the fruit which becomes highly lignified and hard, lending greater mechanical protection to the seed.
23.
In the summer, when the earth has dried out, the leaves fall and the branches become naked and lignified with living fibers . In times of stress, these alterations may be important in increasing the chance of survival, water and reserve material stored in the stems to remain alive by allowing it to have few dormant bud.
24.
This species is noted for having oblate ( flattened spheroid ) rather than ovoid fruit, infrafoliar inflorescence ( rather than interfoliar ), a peduncle not exceeding long ( rather than one up to long ), a thick leathery peduncular bract which rolls up on when itself when abscised ( rather than a heavily lignified peduncular bract thick, which does not deform when abscised ) and 15 stamens ( rather than 18 21 ).
