712 RUBBER 



difference, except in one instance which I will mention, 

 is wholly a matter of environment. Seeds of the so-called 

 C. lactiflua from Soconusco have been sown on the 

 Isthmus of Tehuantepec; the resulting trees scarcely 

 yielded any latex at all; it certainly did not flow, but had 

 to be brushed out of the cuts. A number of abandoned 

 plantations in other parts of Mexico were planted with 

 Soconusco Castilloas C. lactiflua, if you will. Result: 

 they are abandoned. I have tapped trees at r say, 2,000 ft. 

 altitude in Soconusco, not more than five miles from La 

 Zacualpa. They ought to have been C. lactiflua, but 

 there was scarcely any latex. A little froth oozed into 

 the cuts, but it was not fluid. Managers of Castilloa 

 estates in other parts of Mexico, where the cultivation 

 had been a dead failure, have visited Soconusco, and have 

 examined the trees. So far as I know none of them ever 

 saw any difference botanically or in appearance, so I can 

 only give my opinion for what it is worth, viz., that with 

 one exception the only difference is in the environment 

 soil, rainfall, climate, freedom from Northers, etc. 



There are, however, some trees on every Castilloa 

 plantation which the tappers pass by. They call them 

 4 Hule Macho." Hule is the Spanish word for the 

 Castilloa rubber tree. Macho is a he-mule. My atten- 

 tion has been called to a few of these trees, which never, 

 I believe, yield latex. They are easily recognizable. The 

 bark is of a reddish-brown colour and often hairy, but 

 there are very few of them. They may be a different 

 species, perhaps allied to the " Toonu " of Nicaragua 

 and Costa Rica, but by " Hule Macho " the Indian tapper 

 either means a male Castilloa or a mule Castilloa a cross. 

 I am not aware that they flower and seed, or that any 

 botanist has studied them. Be that as it may, the " Hule 

 Macho " is the only species of Castilloa in Mexico 

 different from C. elastica that I am acquainted with. 



