Families

Gnetaceae

The Gnetaceae is a family of tropical trees and shrubs, rarely climbers, in the order Gnetales, composed of one genus, Gnetum, with 30 or more species. The Leaves are opposite, large, green and without stipules.  The flowers are unisexual.  The fruit is fleshy and winged with drupaceous seed.

 Graminae (Poaceae)

The grasses or Graminae comprise some 9000 species grouped into about 650 genera.  Although not the largest, the family is ecologically the most dominant and economically by far the most important in the world.  It provides all the cereal crops (including rice), most of the world’s sugar as well as bamboos, canes and reeds.  In a typical grass the system is fibrous and often supplemented by adventitious roots from the lower nodes of the stem.  Branching occurs mainly at ground level and the upright stems are cylindrical.  The leaves are bourne in two rows at intervals along the stem, their point of origin being termed a node, and they are composed of two parts, sheath and blade.  The fruit is a caryopsis, although some bamboos have a rather fleshy pericarp.  In many species, the fruit is viable for 5 years or so; while a few exceed 30 years.