THE CENTRAL AMERICAN RUBBER TREE 217 



Other sheets are added in the same way until a cake of 

 rubber of sufficient size is obtamed. 



In British Honduras the juice of the " Moon " vine is also 

 used to coagulate Castilloa latex, and the rubber is made 

 into cakes, which are pressed in order to remove as much 

 of the liquid as possible. 



The natives also coagulate Castilloa latex by the 

 addition of solutions of alum, wood ashes, or soap ; by 

 boiling ; or by allowmg it to stand in holes in the ground 

 until coagulation occurs. 



In certain districts of Central America the latex of 

 the Castilloa trees does not flow freely, but coagulates 

 in the incisions. In these cases the rubber is collected 

 in the form of " scrap." 



Much of the Castilloa rubber obtained by the preceding 

 methods is of inferior quality, owing to defective pre- 

 paration, and consequently realises a comparatively low 

 price in the market. 



Cultivation of Castilloa Trees. — It has been mentioned 

 already that very large plantations of Castilloa trees have 

 been established durmg recent years in several countries, 

 particularly in ^lexico, and a short account of the methods 

 of cultivation and of preparing the rubber may be given. 



The trees are usually grown from seed, but they can 

 also be easily raised from cuttings. As the seeds quickly 

 lose their germinating power they require to be specially 

 packed for transport, the most favourable conditions 

 being that they should be kept sufficiently moist to 

 prevent loss of vitality without inducing actual germina- 

 tion. Trees from three to four years old are stated to 

 give the best seed for planting purposes. 



In the early experiments the seeds were sown in 

 nurseries, and the seedlmgs transplanted when they were 

 four to six months old or when they had attained a height 

 of 10 to 12 in. Sometimes, however, the young plants 

 were not moved from the nurseries until they were twelve 

 months old, when they were usually from 5 to 12 ft. high. 

 In the latter case the roots were cut off 5 to 6 in. below 

 the surface of the soil and the stem was reduced to 3 ft. ; 

 the stumps thus obtained were then planted in the re- 

 quired positions. 



On the Mexican plantations, however, it is now custo- 

 mary to sow seeds " at stake," that is, in the position 



