ttle which have an extremely rare and fine fur, in place of the
ordinary pile of hair. The supply of food, whether abundant or scanty,
is one of the most efficient causes of variation known to be within the
control of man. A due consideration of the natural effects of climate
and food is a point worthy the careful attention of the
stock-husbandman. If the breeds employed be well adapted to the
situation, and the capacity of the soil be such as to feed them fully,
profit may be safely anticipated. Animals are to be regarded as machines
for converting herbage into money.

The bestowal of food sufficient, both in amount and quality, to enable
animals to develop all the excellencies inherent in them, and yield all
the profit of which they are capable, is something quite distinct from
undue forcing of pampering. The latter process may produce wonderful
animals to look at, but neither useful nor profitable ones, and there is
danger of thus producing a most undesirable variation, since in animals
the process may be carried far enough to produce barrenness. Instances
are not wanting, particularly among the more recent improved
short-horns, of impotency among the males and of barrenness among the
females; and in some cases where the latter have borne calves, they have
failed to secrete sufficient milk for their nourishment. Impotency in
bulls of various breeds has, in many instances, occurred from too high
feeding, especially when connected with a lack of sufficient exercise. A
working bull, though perhaps not so pleasing to the eye as a fat one, is
a surer stock-getter; and his progeny is more likely to inherit full
health and vigor.

_Habit_ has a decided influence toward producing variations. We find in
domestic animals that use--or the demand created by habit--is met by a
development or change in the organization adapted to the requirement.
For instance, with cows in a state of nature, or where required only to
suckle their young, the supply of milk is barely fitted to the
requirement. If more is desired, and the milk is drawn completely and
regularly, the yield is increased and continued longer. By keeping up
the demand there is induced, in the next generation, a greater
development of the secreting organs, and more milk is given. By
continuing the practice, by furnishing the needful conditions of
suitable food and the like, and by selecting in each generation those
animals showing the greatest tendency toward milk, a bree