498 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1931 



probably are contributing at least half of the cotton that is produced 

 in the United States. The crops that have been raised from this 

 type of cotton would have aggregate values of many billions of 

 dollars. 



Other superior types of Upland cotton have come from Mexico 

 and Guatemala in the present century. A cotton from the State of 

 Durango in northern Mexico was grown successfully in many dis- 

 tricts from southern Virginia to the irrigated valleys of southern 

 California, and later was replaced by the Acala cotton, another 

 Mexican variety which is well adapted to conditions of production 

 over a large part of the American Cotton Belt. The native cottons 

 of Guatemala and southern Mexico were studied for several seasons, 

 beginning in 1902, by expeditions sent out by the United States 

 Department of Agriculture to learn the possibilities of production 

 in the presence of the boll weevil. In the summer of 1906 a cotton 

 expedition crossed Guatemala from the east by way of Panzos, 

 Purulha, Salama, Rabinal, Quiche, Totonicapan, Quezaltenango. 

 and Huehuetenango, passed the Mexican border at Nenton, and 

 traversed the State of Chiapas through Comitan, Ocosingo, and Salto 

 de Agua. The existence of a superior type of cotton was recognized 

 at Ocosingo, and in December of the same year another expedition 

 to southern Mexico obtained a supply of seed at a town called Acala. 

 A select stock bred from this seed has been grown extensively in 

 recent years both in the United States and in Mexico. Most of the 

 cotton of the irrigated valleys of the Southwestern States is of this 

 Acala variety, and several advantages over the Texas Big-Boll cot- 

 tons have been shown. The plants are of more erect habit, with more 

 open foliage and greater resistance to adverse conditions. Larger 

 crops of bolls can be set in shorter periods, and the fiber quality is 

 superior. Eventually the Acala cotton may be used as extensively 

 as the Texas Big-Boll cottons, if adequate supplies of pure seed can 

 be established and maintained. 



DOMESTICATION OF QUININE AND RUBBER 



Two important domestications of South American plants were 

 accomplished in the last century and may be credited to the scientific 

 interest and initiative of one man — Sir Clements Markham. Fore- 

 seeing that the natural supplies of quinine and rubber would soon 

 be inadequate, a systematic project for agricultural production of 

 both commodities was undertaken and, after many vicissitudes, 

 accomplished. 



Markham and his assistants explored the forests of the eastern 

 Andes in Peru and Ecuador and carried many kinds of Cinchona 



