THE PALM TREES OF BRAZIL. 



391 





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Fig. 5. The Spiny 

 Trunk of a Bactris. 



After the nut sprouts from the ground a rootlet starts from the 

 young trunk a few inches above the soil and grows downward to the 

 earth; then another and another starts out a little higher up, each 

 growing down into the ground. As the tree increases 

 in size these roots continue to grow outward and 

 downward always at an angle that will most effect- 

 ively brace the trunk. I have seen the roots starting 

 from the trunk seven and a half feet from the ground. 

 Structure of the TrunJc. — The structure of the 

 palm trunk is always the same in that it is made of j^C" 

 fibro-vascular or horny bundles and parench}Tna or 

 pith; as a rule, too, the horny bundles are grouped 

 together near the surface of the trunk, while the cen- 

 tral portion holds most of the pith. Seen in cross- 

 section the palm trunk is very like the stalk of the 

 Indian corn. There is, however, a marked variation 

 among palms in the direction of these bundles through 

 the stems, for in some they ascend the trunk in a vertical plane while in 

 others they take a spiral direction, not keeping parallel with each other 

 but crossing one another in a bewildering maze. As these hard bundles 

 are what give strength and resistance to the palm trunk, it will be seen 

 that the possibility of splitting some of the trunks must depend upon 

 the direction of the fibro-vascular bundles. In the Iriartia or paxiuha 

 the fibro-vascular bundles lie in a vertical plane and are parallel, so that 

 a section of the trunk of this palm splits with ease, and for this reason 

 it is extensively used for umbrella handles, walking canes and such 

 like purposes. Some of the palm woods admit of a beautiful polish, 



and, in these cases, the winding 

 directions of the bundles cause 

 them to be cut off at various 

 angles and render the orna- 

 mental pieces made of them 

 very beautiful. The fibro- 

 vascular bundles vary greatly 

 in color in the different palm 

 trunks, some of them being 

 nearly white, others amber- 

 colored, others black and still 

 others dark brown; most of 

 them have a waxy, horn-like luster, and all of them are, when mature, 

 exceedingly hard. 



The purely mechanical office which these fibro-vascular bundles 

 perform is necessarily of the utmost importance in giving character 

 and form to the trunk. They extend also from the tnmks out into 



Fig. 6. The Roots of an Ordinary Palm. 



