History of Animals
than the left kidney, and, be the two kidneys ever so fat, there is
always a space devoid of fat in between the two. Animals supplied with
suet are specially apt to have it about the kidneys, and especially
the sheep; for this animal is apt to die from its kidneys being
entirely enveloped. Fat or suet about the kidney is superinduced by
overfeeding, as is found at Leontini in Sicily; and consequently in
this district they defer driving out sheep to pasture until the day is
well on, with the view of limiting their food by curtailment of the
hours of pasture.
The part around the pupil of the eye is fatty in all animals,
and this part resembles suet in all animals that possess such a part
and that are not furnished with hard eyes.
Fat animals, whether male or female, are more or less unfitted for
breeding purposes. Animals are disposed to take on fat more when old
than when young, and especially when they have attained their full
breadth and their full length and are beginning to grow depthways.
And now to proceed to the consideration of the blood. In
sanguineous animals blood is the most universal and the most
indispensable part; and it is not an acquired or adventitious part,
but it is a consubstantial part of all animals that are not corrupt or
moribund. All blood is contained in a vascular system, to wit, the
veins, and is found nowhere else, excepting in the heart. Blood is not
sensitive to touch in any animal, any more than the excretions of
the stomach; and the case is similar with the brain and the marrow.
When flesh is lacerated, blood exudes, if the animal be alive and
unless the flesh be gangrened. Blood in a healthy condition is
naturally sweet to the taste, and red in colour, blood that
deteriorates from natural decay or from disease more or less black.
Blood at its best, before it undergoes deterioration from either
natural decay or from disease, is neither very thick nor very thin. In
the living animal it is always liquid and warm, but, on issuing from
the body, it coagulates in all cases except in the case of the deer,
the roe, and the like animals; for, as a general rule, blood
coagulates unless the fibres be extracted. Bull's blood is the
quickest to coagulate.
Animals that are internally and externally viviparous are more
abundantly supplied with blood than the sanguineous ovipara. Animals
that are in good condition, either from natural causes or from their
health having been attended to, have the blood neither too abundant-as
creatures just after drinking have the liquid inside them in
abundance-nor again very scanty, as is the case with animals when
exceedingly fat. For animals in this condition have pure blood, but
very little of it, and the fatter an animal gets the less becomes
its supply of blood; for whatsoever is fat is destitute of blood.
A fat substance is incorruptible, but blood and all things
containing it corrupt rapidly, and this property characterizes
especially all parts connected with the bones. Blood is finest and
purest in man; and thickest and blackest in the bull and the ass, of
all vivipara. In the lower and the higher parts of the body blood is
thicker and blacker than in the central parts.
Blood beats or palpitates in the veins of all animals alike all
over their bodies, and blood is the only liquid that permeates the
entire frames of living animals, without exception and at all times,
as long as life lasts. Blood is developed first of all in the heart of
animals before the body is differentiated as a whole. If blood be
removed or if it escape in any considerable quantity, animals fall
into a faint or swoon; if it be removed or if it escape in an
exceedingly large quantity they die. If the blood get exceedingly
liquid, animals fall sick; for the blood then turns into something
like ichor, or a liquid so thin that it at times has been known to