THE PRINCIPAL SPECIES OF COTTON 33 



are mostly cultivated cottons, the most important species 

 being Sea Island cotton (Gossypium barbadense). 



Section 5. Naked-seeded cotton with bracteoles 

 quite free and floral glands absent. So far as known, 

 only one species belongs to this section (Gossypium 

 Kirkii). This is a wild cotton found in east and central 

 Africa. It has never been seen under cultivation. 



37. The extensively cultivated species. A relatively 

 large number of cotton species have been described. Only 

 a small number of these are of decided agricultural im- 

 portance. The principal species are grouped into Ameri- 

 can and Asiatic cottons. The species comprising the 

 American group are Upland cotton, Sea Island cotton, 

 and Peruvian cotton. The important species of the Asi- 

 atic group are Indian cotton and Bengal. 



38. American upland cotton (Gossypium hirsutum). 

 This species forms more than 99 per cent of the cotton 

 crop of the United States. It embraces both the short- 

 staple and the long-staple varieties of upland cotton. The 

 chief difference between these two classes of cotton lies 

 in the length of the lint, that of short-staple varying from 

 % to l x /8 inches, while the long-staple ranges from 1^ to 

 1J4 inches. Between these classes is an intermediate 

 type known as " Benders ", or "Rivers" which is grown 

 chiefly on bottom land. 



The plants of American upland cotton are erect, rather 

 coarse, much-branched, and relatively short-limbed. 

 The shoots, leaf-stalks, and veins are clothed with an 

 abundance of short hairs, giving the plants a dust-coated 

 appearance. The leaves are generally 3-lobed, the lobes 

 being rather short and blunt. The bolls are not so dis- 

 tinctly pointed as in Sea Island cotton and are usually 

 4-locked, sometimes 5-locked. The seeds are large and 



