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.