398 POPULAR SCIENCE MONTHLY. 



and uppermost of all the leaves — and ends its life as the lowest in the 

 cluster. The shape and size of the cluster of leaves vary somewhat 

 with the age of the tree, but some species differ greatly from others in 

 this respect. Species like the assai, the palmito and the royal palm 

 have long petioles folding completely around the trunk, and shed the 

 lowest leaves as fast as these leaves pass maturity. The clusters of 

 fronds upon palms of this kind are always fresh looking, for they never 

 have dead fronds dangling against their trunks. (See Fig. 1.) Cer- 

 tain other species have the habit of retaining the dead or half-dead 

 fronds for a certain length of time, and these fronds, as they get older, 

 bend downward more and more until they lie against the trunk of the 

 tree. Such palms have nearly round clusters of fronds. The great 

 forests of carnauba or carandd palms along the Paraguay river look 

 like forests of gigantic clover blossoms growing on straight stems. 



The fronds of palms are extensively used by the lower classes in 

 the tropical parts of South America for thatching their houses. Along 

 the seashores, where the coco palms are grown, the leaves are cut as 

 regularly as the nuts, and are used for covering the roofs and often 

 for making the walls of the humble homes of the fishermen. In the 

 Amazonas valley the entire leaves of the ubussu are best adapted to 

 thatching; for this purpose they are frequently carried a hundred 

 miles or more in canoes. 



The young leaflets of palms are widely used in the manufacture of 

 certain kinds of cheap straw hats. The leaflets of the tucum palm 

 yield an excellent fiber — one of the strongest known. 



On account of certain peculiarities of its leaves I may here men- 

 tion the jacitara (Desmoncus), the long, slender, clambering or 

 sprawling palm already spoken of. The jacitara is not precisely a 

 climbing palm but it comes as near to it as a palm can come. Its full- 

 grown stem is hardly larger than a lead pencil but it reaches a length 

 of a hundred feet or more, and it is therefore impossible for it to stand 

 upright. Shortly after it starts from the ground it topples over 

 and rests against whatever happens to be at hand. It has no 

 tendrils and does not wind about its supports, but the structure and 

 habits of its fronds contribute effectively to its ability to support itself 

 against or upon its neighbors. 



The accompanying illustration (Fig. 14) shows the growing end 

 of one of these clambering palms, and beside it is shown the structure 

 of the tips of the fronds. The recurved hooks at the frond tip are 

 quite stiff and are fastened to the midrib with thickened inflexible 

 joints. In the unopened or embryonic fronds the leaflets all point 

 forward toward the tip or external end of the leaf. At the end of 

 these undeveloped leaves are three or four pairs of leaflets, which, like 

 all the rest, point forward. When the frond unfolds, the terminal 



