cies or potencies that enter into the ancestral unit. Different varieties are produced from a common stock upon the same principle that a mathematician, a musician, and a chemist may have a common father. The fruit of the strawberry is the product or resultant of multiple forces operating in and through the physical organization of the plant. Disturb the equilibrium of the producing forces by cultivation, soil, climate, or external conditions, and a strawberry of a different variety may ensue, which the artificer can separate, fix, and perpetuate. Some plants are necessarily more sensitive to varying conditions, permitting vast differences in the seeds themselves, and hence in the immediate reproduction, as in apples and peaches. Effects of long cultivation also enter into the causes why these fail to produce their exact variety. Tendencies that are not in the fruit can not be put there, nor can they be brought out, consequently there is no principle of Evolution discoverable or applicable in development; nor, furthermore, is any necessary. An individual plant or animal being composed of a collection of potencies that together form a unit, just as many faculties form a human character, the varieties that can be developed through the selection of its component tendencies or constituent potencies and their
