DIFFERENT KINDS OF WILD RUBBER 31 



milk. Again, the milk sometimes coagulates much 

 too quickly when it is being cured ; the material pro- 

 duced is then negro-heads instead of fine or even 

 medium Para. 



In the commercial world Para rubber has many 

 secondary names, which tell from which particular 

 district such or such a supply has been obtained. The 

 chief rubber-producing regions in the Amazon country 

 are : 



1 . The Brazilian State of Para, in the Lower Amazon 

 Valley, including the islands in the mouth of the 

 river. One very good quality rubber from this region 

 is called "Caviana," after the island of that name, 

 where it is obtained. 



2. The Brazilian State of Amazonas, in the Upper 

 Amazon Valley. Rubber produced in this State is 

 known generally as " up-river " rubber ; it is also 

 called "Manaos,'' after the great commercial centre 

 of the industry in this region, or "Madeira," after a 

 tributary of that name which gives access to some of 

 the richest rubber lands in the State. 



3. Acre. This is a far interior territory, bordering 

 on Peru and Bolivia. Acre, which is now federated 

 with Brazil, is very famous for its rubber, which, like 

 that of Amazonas, is generally known as " up-river " 

 rubber. 



4. The Brazilian State of Matto Grosso, in the Upper 

 Amazon Valley. At present very little of this vast 

 forest-land between Amazonas and Paraguay has been 

 opened up, but, judging by what has already been 

 seen of its dense jungle, the whole State is a treasure- 

 ground of rubber-trees. Most of the rubber now ex- 

 ported from this district is coarse, and sun-cured 



