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color, which impart a shaggy appearance, and a color that has 

 given the tree its vernacular name " palo amarillo," or yellow 

 trunk, which becomes also the commercial name of this variety of 

 rubber. The flowers appear in January, or there-about, before the 

 appearance of the new leaves, and the fruits mature in June and 

 July. The seeds, which are much like those of the castor-oil, 

 contain about 50 per cent, of a fatty oil, which can be pressed out, 

 and is good for soap-making. 



As soon as the bark is wounded, a milky juice exudes which 

 is very irritant and capable of producing violent inflammation 

 of the eyes if it enters them, as it is quite liable to do in spat- 

 tering when the tree is cut. A part of this latex soon coagulates, 

 but the coagulum is soft and curdy, rather than tough and elastic, 

 like that of most rubber milks. Rather more than half of it does 

 not coagulate at all, except as a result of drying out. The 

 coagulated portion contains the rubber, about ten per cent, of the 

 entire weight, but with it there is more than twice as much resin. 

 It is this intimate mixture of resin with the rubber that compels a 

 resort to different processes for the manufacture of this rubber 

 from those which apply elsewhere in the rubber industry. The 

 separation has to be effected by solvents, and by the aid of 

 special machinery. Nevertheless, the cost is inconsiderable, and 

 the business bids fair to be very profitable. 



The great value of this tree as a rubber-producer lies in its 

 abundance over large areas, and the proximity of the trees to one 

 another, facilitating collection of the milk, as well as the ease 

 with which it can be propagated, and the rapidity of its growth. 

 All that is necessary for propagation is to thrust the newly cut 

 branches into the soil, where they practicallly all grow. From 

 them the tree reaches its full size in from five to seven years. 

 These considerations appear to justify the opinion that if all other 

 sources of rubber were to fail, this one could probably supply 

 the world's entire requirements. 



It may be added that this and several similar .species form a 

 peculiar division of the genus which will in all probability be 

 elevated to generic rank. It is .said that one known as the 

 " palo Colorado," or red trunk, growing in the northern part of 



