414 GENERAL MORPHOLOGY OF PLANTS 



cultivated varieties were derived from tropical species. One of 

 the best varieties is the Sea Island cotton (Gossypium barba- 

 dense from the West Indies) which has very long fibers. The 

 best quality of this variety is cultivated along the coast of South 

 Carolina, Georgia and Florida, Upland cotton (Gossypium 

 herbaceum, probably from southern Asia) is grown back from 

 the coast over a wide area and there are many varieties. The 

 Sea Island cotton is what is called a long-staple cotton, because 

 of the long fibers. Upland cotton is a short-staple cotton, the 

 fiber being much shorter than that of the Sea Island. The long- 

 staple cotton is necessary for some purposes and the Sea Island 

 cotton in consequence is worth nearly twice as much as the 

 upland, but since it can be cultivated over such a small area as 

 compared with the total cotton-growing area the proportion of long- 

 staple cotton is small. Efforts have been made to cross the 

 long and short staple in order to get a variety of cotton with a 

 longer staple than the upland which can be grown in the upland 

 area. A variety has been developed which is improved in these 

 respects. Texas, Louisiana, Georgia, Alabama, Mississippi and 

 South Carolina are the greatest cotton-producing states, but it is 

 also grown in Florida, North Carolina, Kentucky, Tennessee, 

 Missouri and Arkansas. India, Egypt, and the warmer parts of 

 South America and Russia are great cotton-producing countries. 

 The compound pistil forms the capsule or " boll " as it is called. 

 The fibers are attached to the seed. When ripe the boll bursts 

 open and the fluffy white mass of fiber is easily " picked." The 

 fiber is removed from the seed by passing it through a machine, 

 the " cotton gin." A fine grade of oil, resembling olive oil, is 

 obtained from the seed by pressure, and the meal left is used as 

 food for cattle, and for fertilizer. 



586. Chocolate. Chocolate or cacao is obtained from the 

 seeds of the cacao tree ( Theobroma cacao), a native species of 

 Mexico and related to the previous order. It was introduced 

 into Europe by the Spaniards and is cultivated in all tropical 

 countries. The cacao is expressed from the seed, heated and 

 moulded into cakes. An aromatic substance in cacao, known as 



