e species,
or one of its varieties, with the pollen of another species, or one of
its varieties, of the same or a different _genus_. The offspring is
called a hybrid, or mule. Hybrids, with very few exceptions, are
sterile, they fail to propagate themselves from seed, and must, to
preserve them, be propagated by grafts, layers, or suckers. No change is
perceptible in the fruit produced from blossoms upon which the operation
of cross-breeding or hybridizing has been performed; but the seed of
fruits so obtained may be planted with the certainty of producing a
fruit or tuber commingling the qualities, colors, and main
characteristics of both parents.

Experience, however, shows that the characteristics of the male
predominate somewhat in the offspring. To judicious cross-breeding and
hybridizing we owe most of our superior fruits and vegetables. If the
operation were more generally known and practiced by farmers, the most
gratifying results would be soon obtained, not only in the production of
the most valuable varieties of potatoes and other vegetables, but also
in fruits, flowers, and grain of every description.

SMOOTH VS. ROUGH POTATOES.

Other things being equal, smooth potatoes are preferable to those with
deeply-sunken eyes. The starch being most abundant near the skin, not so
much is lost by the thin paring of the former as by the necessarily
deeper paring of the latter.

Varieties usually well formed sometimes grow so knobby and ill-shaped as
to be scarcely recognized. This is caused by severe drought occurring
when the tubers are about two thirds grown, causing them to partially
ripen. On the return of moisture, a new growth takes place, which shows
itself in knobby protuberances.

CUT AND UNCUT SEED.

Many growers argue that potatoes should be planted whole. The only
plausible theory in support of whole seed is, that the few eyes that do
start have a greater supply of starch available from which to obtain
nutriment until the plant can draw support from the soil and atmosphere.
But experiments also demonstrate that if all the eyes except one or two
near the middle be cut out of the seed-potato, such seed will push with
the greatest possible vigor.

Many eyes of the uncut seed start, but the stronger soon overpower the
weaker, and finally starve them out. A plot planted with three small,
uncut potatoes to the hill, and another planted with three pieces of two
eyes each to the hill, will not show much