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THE POPULAR SCIENCE MONTHLY 



A good Collection of Desert Plants : Vegetation of the Plain. 



Photo by F. E. Lloyd. 



slowly that the increment of one season can not be marked without pre- 

 cise measurements, but year by year the lower leaves of the foliage 

 crown die and add to the thatch of dry leaves that cover the trunk be- 

 low. The trunk itself is six inches to a foot in diameter, a mass of 

 spongy tissue with a more dense outer rind. Of these stems the peon 

 makes fences, or sets them palisade-like for the walls of his hut, or hol- 

 lows them out for bee-hives. The leaves of the plant make the most 

 convenient thatch for his hut, and from the fibers of its leaves he makes 

 ropes and sundry other articles of convenience. Palma china, as the 

 native calls it, known to botany as Yucca australis, is a close relative of 

 the preceding and often occurs in the same situations. Usually, how- 

 ever, this plant does not ascend to the heights attained by its neigh- 

 bor, but is a native of the wide valley lands, where it often occurs in 

 great profusion as at Palmas Grandes, a few miles west of Mazapil, and 

 again on the footslopes some twenty miles east of Gamacho. This 

 Yucca is the most striking of all the plants seen on this desert. Eeach- 

 ing a height of 35 to 40 feet, and having a trunk diameter of two to 

 three feet, its upper portion is divided into straggling branches clothed 

 for a foot or two from the tip with rigid outstanding leaves a foot and 

 a half long. The branching of palma china is never symmetrical, but 

 usually both trunk and branches are contorted and arched in various 

 directions. Occasionally one is found straight and tall and beautiful, 



