A Relic of Past Ages
The color photograph print shown above is a six time enlargement of a cactus seedling just after it has poked its head above ground. It will be noticed that the root has already shown its tendency to go deep in the ground and that this, together with the spine-covered upright stalk or slab, reflects the characteristics of immediate ancestry. The more interesting fact, however, and the fact which proved to Mr. Burbank's mind his theory of the original spinelessness of cactus, is to be found in the two smooth leaves extending from the base of the small thorny slab. These leaves, though rudimentary, and dropping off a few days after the cactus is above the ground, are reminders of a former age when all cactus plants had stalks or leaves that were as smooth as these.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 1 Chapter 1