The Dilleniidae

What Family?

Significant features:  Floral structure is an expression of extreme reduction.  The pistillate flower is represented by only a single, compound pistil and the staminate flower is, in Salix species, just two stamens.  These imperfect flowers are produced in catkins and most species of the family are dioecious.  While the reproductive adaptive syndrome of this family mimics that of families of the Hamamelidae, there is general agreement that this similarity is not based on common ancestry and most classification systems place this family in a position well removed from families of the Hamamelidae.  This points out the importance of the gynoecium in that the primary structural difference between this family and the other 'amentiferous' flowering plants is the capsular fruit.  As indicated by the local name for our most common poplar - 'cottonwood' - seeds emerging from capsules are comose (with a tuft of trichomes) and, as a result, all reproductive events - pollination, fertilization and dispersal of the product - are wind-mediated in this family.  

Return to the Biology 301 homepage