16 



FIELD CROPS'FOR THE COTTON-BELT 



abruptly, as this retards the development of the 

 boll. 



15. The flowers (Figs. 4-6). — Cotton flowers are large 

 and rather conspicuous. At the juncture of the peduncle 

 and the flower is borne a three- (sometimes four-) leaved 

 involucre. The calyx is short and composed of five, united 

 sepals, presenting a cup-shaped appearance. The corolla 

 is free from, but inserted beneath, 

 the pistil. There are five petals, 

 which are often grown together at 

 their base and attached to the 

 lower part of the stamen-tube. 

 The stamens are numerous; the 

 anthers one-celled and kidney- 

 shaped; the pollen-grains spheroid 

 in shape, heavy and waxy. The 

 ovary is sessile and three- to five- 

 celled. The pistil is divided into 

 parts or stigmas, from three to 

 five in number. In American up- 

 land cotton the pistil is divided 

 stigmas, while three is the pre- 

 Sea Island cotton. The number of 



FiQ. 6. — stamens and 

 stigmas of Egyptian 

 cotton. 



into four or five 



vailing number 



stigmas present indicates the number of locks of seed 



cotton that will develop in that particular boll. 



In upland cotton the flowers are a creamy-white color 

 on the morning that they open. They change to a reddish 

 color the second day, and later fall. The flowers of the 

 Sea Island cotton are yellowish in color. 



16. The bolls. — The ovary of the cotton flower con- 

 tains from few to many ovules. After these ovules have 

 been fertilized by the pollen-grains, the pistil develops 

 into a more or less thickened, leathery capsule called the 



