The extraction of the latex of the “castillôa” can be done in the same way as that of the latex of the heveas; the caucheiros allege, however, that the cupim introducing itself into the wounds made by the incisions soon causes the death of the plant. Thus they argue that if the tree is condemned, the best way is to cut it down so as to obtain the greatest benefit possible out of it, by the complete utilization of the latex which each tree contains. That reasoning, however, has no foundation in fact. * * * * * The exploitation of the castillôa is done in the following manner: the “caucheiro” penetrates into the forest and marks each castillôa tree that he finds, with a cut from his knife, which incisions correspond to a sign of possession for extraction later on. Once he has discovered a certain number of these trees, he constructs a temporary wooden hut for himself and then begins his work. In the first place he clears the brush-wood around each tree and cleans away the undergrowth from the ground, he then opens small cavities in the lower part of the trunk into which he fixes the “porringers,” small vessels made of tin, which are to receive the latex. This done he strikes the tree with oblique “entalhas” of from 1 to 1½ metres in length, canalizing the latex which commences to run from the extensive wounds, by means of mud gutters. At the end of 24 hours the little tin vessels are full and their contents are then all poured into a pail, the “caucheiro” commencing thereafter to cut down the tree, so as to get the full benefit of the latex, existing in the superior part of its trunk. The tree as a general rule is cut at a point above that where the incisions were made, the tree thus remaining suspended above the ground at one end by the lower part of the trunk, where it remains fixed and at the other by its own branches. Along the whole length of the trunk at about a distance of an arm’s length from each other, new circular incisions are made and in corresponding cavities on the ground are placed the receiving cups. The latex thus gathered is collected into a pail. The thickening is done with a solution of common soap about 125 grammes to a pail of water, two pailfuls of that solution being necessary to thicken 30 litres of latex. They also employ the juice of a liane called =vetilla= which by the description given seems to belong to the convolvulas family—the =Ipomea patatas=.