House plants, varied group of plants grown indoors and requiring no special care. They are usually grown singly in pots, but can also be grouped and planted together in dish gardens and terrar...

Lewisite, liquid chemical compound used as a poison gas. Like mustard gas and nitrogen mustard, it is a blistering agent; when inhaled, it is a powerful respiratory irritant. The absorption of...

Petal, one of the four basic parts of a flower, next innermost organ from the sepal. The whorl of petals is known collectively as the corolla [Lat.,=little crown]. The number of petals is usua...

Stamen, one of the four basic parts of a flower. The stamen (microsporophyll), is often called the flower's male reproductive organ. It is typically located between the central pistil and the ...

Perfume, aroma produced by the essential oils of plants and by synthetic aromatics. The burning of incense that accompanied the religious rites of ancient China, Palestine, and Egypt led gradu...

Saxifrage, common name for several members of the Saxifragaceae, a family of widely varying herbs, shrubs, and small trees of cosmopolitan distribution. They are found especially in north temp...