A diverse set of flowering plant orders that lacks a distinct set of key characters.  General trends or features of the Subclass include: with the exception of the Dilleniales, which stands as a structural link to the Magnoliidae, all are syncarpous more than 1/3 of the species show parietal placentation about 1/3 of the species are sympetalous The Order Dilleniales (two families) is placed at the base of the Dilleniidae and also by Cronquist as a structural link to the basal flowering plant subcalss, the Magnoliidae, mainly due to lack of connation in the gynoecium, as expressed by the peony (Paeonia - Paeoniaceae) as depicted this figure (left) from the Delta family description.

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