Disc Flower (left). Ray Flower (Right)
Note: Disc flowers have 5 petals fused together to form a tube (blue). Ray flowers have 5 petals fused together, but they do not form a tube. Instead, the would be tube is "unfurled" to form a conspicuous, long, ribbon- like ray (blue). Below the petals is the ovary (green), which, upon fertilization, becomes a fruit, or "seed," called an achene. Positioned above the ovary is the pappus, a cluster of bristle-like filaments that facilitates wind blown dispersion of the achene. The stamens, or male parts of the flower, are contained within the tube of petals. They are not illustrated here. The stigma of the pistil, however, is illustrated, in red. The stigma is divided into two segments, and appears forked. It is connected to the ovary by a "style," which is not shown.
Flowering head showing 3 disc flowers, 2 ray flowers, receptacle (red cup-like structure), involucral bracts (black tents) on outer surface of receptacle, and stem or peduncle(red rectangle).
Note: See diagram above for structural details of disc and ray flowers.