From the September 23, 1933, issue

LEAFY SUCCULENTS SOLVE PROBLEM SET BY DESERT

Desert plants have a particularly hard problem to solve, set by that old Sphinx, the desert itself, and if they fail to solve it, the penalty is the same as that exacted in the old Greek myth–they must die. They must spread a sufficient chlorophyll surface to the sun to enable the indispensable food-making processes to go on; yet they must deny the imperious demands of the water-greedy fiend, the dry desert wind.