136 THE HUMAN SIDE OF PLANTS 
soming. It is because of this long period of “an- 
nual payments,” that many people erroneously be- 
lieve the Agave, as it is botanically known, blos- 
soms only once in a century. The blossoms, which 
really appear usually about once in fifteen years, 
develop very rapidly, and thus require a large 
quantity of ready prepared food-material. As the 
living plant benefits by this foresight, its imsur- 
ance might be classed under the head of an “endow- 
ment policy.” 
Among the striking illustrations of plants that 
have developed life insurance to an art none are 
more worthy of mention than the cacti. These 
giant inhabitants of the desert regions have long 
ago learned the value not only of saving for the 
rainy day, but of saving on the rainy day: their 
“hay day” is when it rains! It is at this rare time 
that they are enabled to drink up a sufficient quan- 
tity of water to fill their internal sponges, or small 
cisterns, and thus insure themselves against the 
long-continued drought to follow. 
These cacti have become very strong and cour- 
ageous, for they have fought and won many bat- 
tles. Their spines defend them from grazing ani- 
mals, and their bodies have become so shaped as to 
protect them from too much sunshine, which might 
cause their carefully stored water to evaporate; thus 
