BOTANICAL DESCRIPTION OF COTTON 439 



teenth century. Since that time the growth of the industry 

 has been rapid. (Section 607.) . '. \. i 



602 Botanical Description. Cotton belongs to the Mal- 

 vaceae, or mallow, family, and is the only member of that 

 family which is an important cultivated plant. There is 

 a number of species of cotton, ranging in form from" bushy 

 herbs to trees. They are all natives of tropical regions and 

 are probably all perennials, though the cotton which is 

 grown in the United States has been developed into an 



annual. ,,«.', x 



The ordinary upland cotton, of which by far the greater 

 part of the crop consists, is Gossypium hirsutum. It is a 

 vigorous annual plant, with a branching, upright stem and a 

 taproot with numerous lateral branches. The depth to 

 which the taproot penetrates varies greatly m difierent 

 soils In sandy soils it may reach a depth of 2 feet or more, 

 while in heavy clay it may be only a few inches long or al- 

 most entirely lacking. The laterals or feeding roots are 

 only a few inches below the surface. The stem grows from 

 2 to 6 feet high, according to the variety, the soil, and the 

 season. The usual height is from 2}^ to 3^ feet. The 

 length and number of the branches and the length of the 

 internodes, or '^joints," depend on the same factors as the 

 height of the plant. . 



The leaves of cotton are alternate, from 3 to 6 mches long, 

 with a width shghtly less than the length, the lower ones 

 heart-shaped, the upper more or less three or five-lobed. 

 The flowers are large and showy, being from 3 to 4 inches 

 across They are white when they first open, but turn rosy 

 pink on the second day, so that a field in bloom is very at- 

 tractive. Cotton is commonly open-pollinated. 



The fruit, or ''boll," is enclosed by leafy bracts when 

 small, and is' then commonly known as the ''square.'' It 

 finally develops into a pointed, somewhat egg-shaped body, 

 about the size of a small hen's egg, closely packed with seeds 



