MULES, among gardeners, denote a sort of vegetable monsters produced by putting the farina fecundans of one species of plant into the pistil or utericle of another.
The carnation and sweet-william being somewhat alike in their parts, particularly their flowers, the farina of the one will impregnate the other, and the feed so enlivened will produce a plant differing from either. An instance of this we first had in Mr Fairchild's garden at Hoxton; where a plant is seen neither sweet-william nor carnation, but resembling both equally: this was raised from the feed of a carnation that had been impregnated by the farina of the sweet-william. These couplings being not unlike those of the mare with the ass, which produce the mule, the same name is given them; and they are, like the others, incapable of multiplying their species.
This furnishes a hint for altering the property and taste of any fruit, by impregnating one tree with the farina of another of the same class; e. gr. a codlin with a pear-main, which will occasion the codlin so impregnated to last a longer time than usual, and to be of a sharper taste. Or if the winter-fruits be fecundated with the dust of the summer kinds, they will ripen before their usual time. And from this accidental coupling of the farina of one with another, it may possibly be, that an orchard where there is variety of apples, even the fruit gathered from the same tree differ in their flavour, and in the season of maturity. It is also from the same accidental coupling that the numberless varieties of fruits and flowers raised every day from feed proceed.
Wild or Fecund Mule. See EQUUS, p. 712.