COTTON 



COTTON 



247 



COTTON. Gossypium. Malvaeece. Figs. 354-367. 



By Herbert J. Webber and E. B. Boykin. 



The cotton of commerce is the hair or fiber on seeds 

 of plants belonging to the genus Gossypium, a mem- 

 ber of the Mallow family. This genus is distinguished 

 from the other genera of the family by the presence 



Fig. 354. A cotton flower, and a bud 

 or "square," showing the bracts. 



of three to five bracts surrounding the flowers, and 

 by the seed being covered with wool. Many attempts 

 have been made to classify and limit the species of 

 Gossypium, but so far the authorities have failed 

 to agree. The great variability and tendency to 

 hybridize make it very difiicult to determine to what 

 species a given plant may belong. However, it is 

 commonly conceded that there are only a few spe- 

 cies whose products enter into commerce, and that 

 the bulk of the production is from two species, 

 namely, G. hirsutum, which furnishes the upland 

 cottons (Pigs. 101, 355, 356, 357), and G. Barba- 

 dense, the source of the sea-island and Egyptian 

 cottons (Figs. 100, 356, 357). The ordinary upland 

 cotton in American literature has been commonly 

 referred to as G. kerbaeeum, but after a careful 

 study of types Mr. L. H. Dewey, of the United 

 States Department of Agriculture, has concluded 

 that this is an error and that our upland cotton, 

 which is apparently derived from a wild Mexican 

 variety, is . G. hirsutum. In the United States G. 

 hirsutum and G. Barbadense are the only two species 

 that are cultivated commercially. The crop of 

 India, which, aside from that of the United States, 

 is the largest produced by any country, is probably 

 derived principally from varieties of G. herbaemm, 

 while the Egyptian crop is produced by varieties 

 which are supposed to belong to the species G. Bar- 

 badense. Thfi Egyptian cotton varieties resemble 



sea-island cotton very closely in all of their prin- 

 cipal characters aside from the lint, which in some 

 of the varieties, such as Mit-afifl and Ashmouni, is 

 light brown and rather coarse and crinkly. 



All cultivated species are perennial in climates 

 without frost, but in cultivation they are usually 

 treated as annuals^ The plants are mostly shrubby, 

 more or less branching and two to ten feet high. 

 The roots consist of several laterals, and a tap- 

 root which penetrates the soil to a considerable 

 depth. The limbs of sea-island are smooth, while 

 those of upland are covered with delicate, whitish 

 hairs. The leaves are three- to five-lobed — sea- 

 island usually having three and the upland five. 

 The flowers are perfect and resemble the holly- 

 hock or hibiscus. When newly open they are large 

 and white in upland, turning red with age, and 

 creamy yellow in sea-island, with a purple spot 

 at the base of each petal. They are surrounded 

 by three to five fringed or deeply cut bracts form- 

 ing the "squares" — the number corresponding to the 

 number of cells in the bolls or pods. These bracts 

 are much larger and the indentations are deeper 

 and more numerous in sea-island than in upland 

 varieties. Stamens are many, united in a tube about 

 the single compound pistil; stigmas three to five. 

 The fruit consists of three- to five-celled capsules 

 or "bolls" which burst open at maturity through 

 the middle of the cells, each cell liberating seven 

 to ten seeds covered with long fibers. The fiber is 

 a tubular hair-like cell -rhsTs to r^Vij of an inch in 

 diameter, somewhat flattened, and spirally twisted. 

 It is this latter character which gives the cotton 

 its spinning qualities. The length, tenacity and 

 fineness of the fibers determines the value of the 

 cotton. Sea-island excels upland in these respects 

 and therefore commands a much better price. Sea- 

 island cotton seeds are small, black and smooth, 

 while, as a rule, upland seeds are larger, and, after 

 the fiber is removed, are covered with a dense whit- 

 ish or greenish fuzz. The bolls of sea-island rarely 

 contain more than three 

 cells, while those of up- 

 land usually have four 

 and sometimes five. 

 Sea -island bolls are 

 much smaller and more 

 pointed than upland. 



There are many com- 

 mercial varieties i n 

 each of the above spe- 

 cies which have never 

 been classified botani- 

 cally, and whose true 

 history will probably 

 never be known. It is very difficult to classify 

 them, owing to the readiness with which they are 

 cross-fertilized and the great range of variation 

 of the individual plants in a given variety. Some 

 of them possess characters which suggest that they 

 are produced by the hybridization of sea-island 

 and upland varieties, while many seem to be the 

 products of natural variation and selection. 



Aside from the cottons ordinarily classed as 

 sea-island and upland, which are cultivated ex- 



Fig. 355. 

 Mature plant of upland cotton. 



