There are many types of plants in the world today, and many more that are undiscovered. Flowers and vegetables are a common sight in gardens worldwide, but occasionally there are plants that are surprises -- plants that are not quite what they appear to be on the outside. The genus Lithops is one example.

Discovered in 1811 by botanist William John Burchell, the Lithops plant was a surprise find from Africa. William John Burchell was on an expedition on the coast of South Africa cataloging wildlife when he discovered the Lithops plant. He thought he was picking up a handful of brightly colored pebbles when he noticed that the pebbles had roots. The plants do resemble stones, and it is from this fact that their name is derived. Lithos is a Greek word meaning stone, and opsis is a Greek word meaning face, thus the name Lithops means “stone faced."

The plant, a close relative of the cactus and succulent family, grows in small clusters close to the ground. While there is a large system of roots, there is little or no stem on the Lithops plant. The leaves of the plant look like a small rock with a split down the middle. This split allows the plant to divide itself, as well as produce bright white flowers in season. In its native southern hemisphere, the Lithops plant produces these flowers in the summertime. In the Northern hemisphere, however, the plant flowers in winter.

Most often found in nature growing among gravel in sandy soil, the Lithops plant also does fairly well as a houseplant as long as certain conditions are met. They require very little water in summertime, and no water at all during winter. The plants do exceedingly well in almost any type of soil. They also flourish in nearly any type of sun exposure, from full sun to partial shade. The Lithops plants thrive most often when planted in wide, shallow pots that best accommodate their root structures.

There are many subdivisions of the Lithops family. Most of these variations are readily available. Several species, such as Lithops francisci, Lithops hermetica and Lithops werneri, are considered "vulnerable" by the International Union for the Conservation of Nature (IUCN). One species, Lithops optica, is labeled as "near threatened." This may be due to a recent growth in interest in Lithops plants, as well as careless preservation of their natural habitats.

While the number of Lithops being grown as houseplants is growing, the number of wild specimens of Lithops is declining rapidly, according to the ICUN. This may be due to the fact that Lithops plants need to be grown from seeds, or divided from older plants. Cuttings are not usually worthwhile. It is not known whether the preservation of these wild desert plants is possible, but the disappearance of the living stones is not likely in the near future.