Perfect flowers have both sets of essential organs.
Imperfect flowers have but one set of essential organs.
Staminate (or male) flowers have only stamens;
Pistillate (or female) flowers have only pistils.
Neutral flowers have neither.
THE STAMEN
The stamen consists of two parts—the filament and the anther. The filament is the stalk of the stamen. The anther is the little case holding the pollen, or powdery substance, which, falling upon the stigma, is conducted downward into the ovary, where it quickens the ovules into life. The anther normally consists of two cells, which more often open lengthwise for the discharge of the pollen, though they sometimes open by terminal pores or chinks, or by uplifting lids.
Stamens sometimes undergo a morphological change, taking the form of scales or other bodies (as is the case in many of our Brodiæas), when they are called staminodia.
THE PISTIL
The pistil is the organ occupying the center of the flower. It consists of three parts—the ovary, or the enlarged part below, consisting of one or more cells or cavities, and containing the ovules, or unfertilized seed; the style, or the stem which upholds the stigma; the stigma, or the roughened portion which receives the pollen.
The pistil is simple, when it has but one ovary, style, stigma, etc.; compound, if any one of these is duplicated.
THE FRUIT
The fruit is the ripened ovary. After the ovules have been fertilized, the ovary is called a pericarp. Fruits may be either fleshy or dry.