Compositae

Compositae, largest family of flowering plants, including more than 20,000 species. Their characteristic feature is that what appears to be a single flower is actually a flower head made up of a large number of florets. Those in the center, closely packed and resembling the pile of a rug, are simple tubular flowers having both stamens (the male part) and pistils (the female part). Surrounding them is a ring of ray flowers, often mistaken for petals, which have flattened corollas and are sterile or bear only pistils.