Plant from a dry climate capable of conserving water for longer that other plants, due to structural adaptations like dense pubescence, thick epidermis and resin cover which delay transpiration. Certain mangrove plants are also xerophytes, because water absorption is hindered by excess of salt.
Double flowers: Flowers that have at least two rings of petals. In general, the stamens and pistils in the center of the flower are replaced by more petals. Double flowers are usually cultivars. For example, some varieties of roses. (Also see Simple Flower, and Semi-Double Flower).