A plant family of the order Lamiales. It is characterized by simple leaves in opposite pairs, cystoliths (enlarged cells containing crystals of calcium carbonate), and bilaterally symmetrical and bisexual flowers that are usually crowded together. The common name for Ruellia of wild petunia is easily confused with PETUNIA.

Those nucleic acid sequences that function as units of heredity which are located within the CHLOROPLAST DNA.

Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.