This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
Cotton belongs to the genus Gossypium (name used by Pliny), of the Malvaceae. The species are now much confused, but it is generally agreed that the sea island cotton is of the species G. barbadense, Linn. The upland cotton is probably derived chiefly or wholly from G. hirsutum, Linn. The former is native in the West Indies. The nativity of the latter is in dispute, but it is probably Asian. The cotton flower is mallowlike, with a subtending involucre of three large heart-shaped bracts. The carpels or cells of the pod are three to five. These carpels break open, and the cotton covering of the seeds makes a globular mass,-the cotton boll (Fig. 1082). Cotton is not a horticultural crop, and is therefore not considered in this work. The reader will find "The Cotton Plant" (published by the Dept. of Agric, Bull. 33), a useful monograph. Consult Cyclo. Amer. Agric, Vol. II, p. 247.
Fig. 1082. A cotton boll.