ABSTRACT

If then every change of life is relative to a change of environment, it is clear that there are two ultimate factors

is the opportunity for a further revelation of life, wholly inoaloulable in advanoe. We find not simply "variation," but, as de Vries has so oompletely shown, "mutation." To illustrate, the oommon primrose (primula officinaZis) has a variety whioh loves damper and oooler soil (primula elatior), but we do not have all degrees of approaoh to the latter variety aooording to the degree of humidity of the soil. Instead we find a plant of a distinotive oharaoter in one kind of environment, a. variety of a distinotive charaoter in another. Differenoes of outer environment are measurable and oontinuous, varieties of organism are immeasurable and discontinuous. It is as if the inoaloulable Proteus-principle of life, eternally lying in wait behind material phenomena, wrought of every physical ohange an organio means· for its own revelation.