162 



than in any other part of America, and mention has already been made 

 of its entry by Pearson under the name of " Brazilian bird lime." The 

 Mango was also brought to Brazil some years hetore it reachfd the 

 West Indies. The cultivation of the tree in these regions, however, 

 does not extend much beyond the coast, being restricted to the warm, 

 moist coastal plains or inland places with similar climatic conditions. 



The tree grows sparsely in the United States in Florida, where the 

 fruit can scarcely be had in sufficient quaniitits to justify its culture for 

 commercial purposes, although a few cases of successful wintering in 

 the open air have been reported as far north as Manatee 



[To he continued.) 



THE CULTURE OF THE CENTRAL AMERICAN 



RUBBER TREE.* 



By 0. F. Cook, Botanist in Charge of Investigations in Tropical 

 Agriculture, U. S. Department of Agriculture. 



Among the more striking results of the industrial progress of the 

 nineteenth century was the rapid multiplication of the uses of rubber 

 and an ever-increasing demand for the raw miterial. For several 

 decades the world's needs were met by the Para district of eastern 

 Brazil, but with steadily advancing prices as an inducement the entire 

 Amazon Valley, and indeed all tropical regions of both hemispheres, 

 have been ransacked in search of additional wiM supplies. It is not 

 yet true, as sometimes represented, that the natural product is exhausted 

 or that a rubber famine is to be anticipated at an early date. Within 

 the last decade the value of good grades of rubber passed from the 

 neighbourhood of 25 cents to a dollar and upward per pound, and the 

 rubber-gathering industry met with an expansion sufficiently rapid to 

 more than keep pace with the demand, so that a period of somewhat 

 more moderate prices has ensued. But with a steady increase in the 

 use of rubbt r in the arts and no very general improvement in the 

 destructive methods of gathering the wild product, it is to be expected 

 that this respite will be brief and that the question of the world's fu- 

 ture supply will soon become more acute. 



The preservation of the wild rubber forests is naturally receiving 

 more and more attention in the countries in which they re so impor- 

 tant a source of wealth, but measures of safety are least likely to be 

 applied m the very remote ani unexploited districts where they would 

 do the most good Rubber is still very largely a product of savage 

 rather than of civilized industr , ; in f ^ct, it is now by far the rnost im- 

 portant contribution of barbarous races to our industrial civilization. 

 While this continu s to be the fact there will be little chuige in tne 

 careless and wasteful methods of the past, but the appreciatio.i of rub- 

 ber forests as permanent sources of income may De expected to in- 

 crease, so that the continued advance in tlie price of rubber no longer 

 means merely the rapid extinction of wili rubber trees, but implies 

 also increased into est in the protection and improvement of the more 

 productive natural forests. Such a tendency is already manifest, es- 



* Extracts from U. S. Dep ^rtment of Agriculture, Bull. No. 49, Bureau of Plant 

 Industry. 



