THE GIANT CACTUS. 641 



mental law of all development ; and as it certainly prevails for 

 earthly life, so it does for the existence of human society. This 

 principle is illustrated, and is destined to be more extensively so, 

 from observations in the polar regions. Translated for the Popu- 

 lar Science Monthly from the Deutsche Euridschau. 



THE GIANT CACTUS. 



Bv Pkof. JAMES W. TOUMEY. 



PEOPLE in general are but little impressed by the many forms 

 of life, be they plant or animal, with which they daily come 

 in contact. A tree of unusual size, or a flower of exceptional 

 form or color, attracts our attention. It is the unusual in Nature 

 which always catches the eye. The New England boy grows to 

 manhood under the widespreading boughs of the American elm, 

 in sight of grass-covered mountains and winding rivers. The 

 natural beauty of his surroundings is a part of himself. So, also, 

 the Papago Indian sees nothing peculiar in the many forms of 

 life characteristic of the region where he makes his home. 



He can not listen to the whispering of the leaves, because the 

 trees of his limited world do not grow them. He knows nothing 

 of tangled woods, but draws his inspiration from the broad, hot, 

 cactus-covered plains and the granite-walled and lava-strewn 

 mountains. 



The many and varied species of cacti, which constitute the 

 vegetation most familiar to him, are the most peculiar of all 

 forms of vegetable life to those who live beyond the limits of our 

 arid region. Of all these strange plants the sahuaro, or giant 

 cactus, on account of its great size and striking aspect, is the most 

 impressive. We can well imagine the feeling of the early ex- 

 plorers when they first came in sight of these towering plants, so 

 abundant on the foothills contiguous to Salt River Valley, and 

 from where they extend southward far into Mexico. The finest 

 and largest specimens that I have ever observed are growing only 

 a few miles from Tucson, on the foothills of the Santa Catalina 

 Mountains, where hundreds may be seen growing on a single 

 acre, many extending their huge green columns to the height 

 of fifty feet. The many ribs which parallel the columns are 

 surmounted by bunches of heavy spines. With great age the 

 spines fall away from the lower portion of the plant, leaving the 

 broad, obtuse ribs devoid of their natural protector. This fact 

 led the first observers to report the plant spineless. 



When lighted, the spines burn readily ; the flame, soon ascend- 

 ing, burning the spines in its path until it reaches the top. From 



