Various Works

antagonistic to fat, for it tends to melt it.

  Animals then, as a general rule, derive advantage from their kidneys

  being fat; and the fat is often very abundant and extends over the

  whole of these organs. But, should the like occur in the sheep,

  death ensues. Be its kidneys, however, as fat as they may, they are

  never so fat but that some part, if not in both at any rate in the

  right one, is left free. The reason why sheep are the only animals

  that suffer in this manner, or suffer more than others, is that in

  animals whose fat is composed of lard this is of fluid consistency, so

  that there is not the same chance in their case of wind getting shut

  in and causing mischief. But it is to such an enclosure of wind that

  rot is due. And thus even in men, though it is beneficial to them to

  have fat kidneys, yet should these organs become over-fat and

  diseased, deadly pains ensue. As to those animals whose fat consists

  of suet, in none is the suet so dense as in the sheep, neither is it

  nearly so abundant; for of all animals there is none in which the

  kidneys become so soon gorged with fat as in the sheep. Rot, then,

  is produced by the moisture and the wind getting shut up in the

  kidneys, and is a malady that carries off sheep with great rapidity.

  For the disease forthwith reaches the heart, passing thither by the

  aorta and the great vessel, the ducts which connect these with the

  kidneys being of unbroken continuity.

  10

  We have now dealt with the heart and the lung, as also with the

  liver, spleen, and kidneys. The latter are separated from the former

  by the midriff or, as some call it, the Phrenes. This divides off

  the heart and lung, and, as already said, is called Phrenes in

  sanguineous animals, all of which have a midriff, just as they all

  have a heart and a liver. For they require a midriff to divide the

  region of the heart from the region of the stomach, so that the centre

  wherein abides the sensory soul may be undisturbed, and not be

  overwhelmed, directly food is taken, by its up-steaming vapour and

  by the abundance of heat then superinduced. For it was to guard

  against this that nature made a division, constructing the midriff

  as a kind of partition-wall and fence, and so separated the nobler

  from the less noble parts, in all cases where a separation of upper

  from lower is possible. For the upper part is the more honourable, and

  is that for the sake of which the rest exists; while the lower part

  exists for the sake of the upper and constitutes the necessary element

  in the body, inasmuch as it is the recipient of the food.

  That portion of the midriff which is near the ribs is fleshier and

  stronger than the rest, but the central part has more of a

  membranous character; for this structure conduces best to its strength

  and its extensibility. Now that the midriff, which is a kind of

  outgrowth from the sides of the thorax, acts as a screen to prevent

  heat mounting up from below, is shown by what happens, should it,

  owing to its proximity to the stomach, attract thence the hot and

  residual fluid. For when this occurs there ensues forthwith a marked

  disturbance of intellect and of sensation. It is indeed because of

  this that the midriff is called Phrenes, as though it had some share

  in the process of thinking (Phronein). in reality, however, it has

  no part whatsoever itself in the matter, but, lying in close proximity

  to organs that have, it brings about the manifest changes of

  intelligence in question by acting upon them. This too explains why

  its central part is thin. For though this is in some measure the

  result of necessity, inasmuch as those portions of the fleshy whole

  which lie nearest to the ribs must necessarily be fleshier than the

  rest, yet besides this there is a final cause, namely to give it as

  small a proportion of humour as possible; for, had it been made of

  flesh throughout, it would have been more likely to attract and hold a

  large amount of this. That heating of it affects sensation rapidly and

  in a notable manner is shown by the phenomena of laughing. For when

  men are tickled they are quickly set a-laughing, because the motion

  quickly reaches this part, and heating it though but slightly

  nevertheless manifestly so disturbs the mental action as to occasion

  movements that are independent of the will. That man alone is affected

  by tickling is due firstly to the delicacy of his skin, and secondly

  to his being the only animal that laughs. For to be tickled is to be

  set in laughter, the laughter being produced such a motion as

  mentioned of the region of the armpit.

  It is said also that when men in battle are wounded anywhere near

  the midriff, they are seen to laugh, owing to the heat produced by the

  wound. This may possibly be the case. At any rate it is a statement

  made by much more credible persons than those who tell the story of

  the human head, how it speaks after it is cut off. For so some assert,

  and even call in Homer to support them, representing him as alluding

  to this when he wrote, 'His head still speaking rolled into the dust,'

  instead of 'The head of the speaker'. So fully was the possibility

  of such an occurrence accepted in Caria, that one of that country

  was actually brought to trial under the following circumstances. The

  priest of Zeus Hoplosmios had been murdered; but as yet it had not

  been ascertained who was the assassin; when certain persons asserted

  that they had heard the murdered man's head, which had been severed

  from the body, repeat several times the words, 'Cercidas slew man on

  mam.' Search was thereupon made and a man of those parts who bore

  the name of Cercidas hunted out and put upon his trial. But it is

  impossible that any one should utter a word when the windpipe is

  severed and no motion any longer derived from the lung. Moreover,

  among the Barbarians, where heads are chopped off with great rapidity,

  nothing of the kind has ever yet occurred. Why, again, does not the

  like occur in the case of other animals than man? For that none of

  them should laugh, when their midriff is wounded, is but what one

  would expect; for no animal but man ever laughs. So, too, there is

  nothing irrational in supposing that the trunk may run forwards to a

  certain distance after the head has been cut seeing that bloodless

  animals at any rate can live, and that for a considerable time,

  after decapitation, as has been set forth and explained in other

  passages.

  The purposes, then, for which the viscera severally exist have now

  been stated. It is of necessity upon the inner terminations of the

  vessels that they are developed; for humour, and that of a bloody

  character, cannot but exude at these points, and it is of this,

  solidified and coagulated, that the substance of the viscera is

  formed. Thus they are of a bloody character, and in substance resemble

  each other while they differ from other parts.

  11

  The viscera are enclosed each in a membrane. For they require some

  covering to protect them from injury, and require, moreover,
that this

  covering shall be light. To such requirements membrane is well

  adapted; for it is close in texture so as to form a good protection,

  destitute of flesh so as neither to attract humour nor retain it,

  and thin so as to be light and not add to the weight of the body. Of

  the membranes those are the stoutest and strongest which invest the

  heart and the brain; as is but consistent with reason. For these are

  the parts which require most protection, seeing that they are the main

  governing powers of life, and that it is to governing powers that

  guard is due.

  12

  Some animals have all the viscera that have been enumerated;

  others have only some of them. In what kind of animals this latter

  is the case, and what is the explanation, has already been stated.

  Moreover, the self-same viscera present differences in different

  possessors. For the heart is not precisely alike in all animals that

  have one; nor, in fact, is any viscus whatsoever. Thus the liver is in

  some animals split into several parts, while in others it is

  comparatively undivided. Such differences in its form present

  themselves even among those sanguineous animals that are viviparous,

  but are more marked in fishes and in the oviparous quadrupeds, and

  this whether we compare them with each other or with the Vivipara.

  As for birds, their liver very nearly resembles that of the

  Vivipara; for in them, as in these, it is of a pure and blood-like

  colour. The reason of this is that the body in both these classes of

  animals admits of the freest exhalation, so that the amount of foul

  residual matter within is but small. Hence it is that some of the

  Vivipara are without any gall-bladder at all. For the liver takes a

  large share in maintaining the purity of composition and the

  healthiness of the body. For these are conditions that depend

  finally and in the main upon the blood, and there is more blood in the

  liver than in any of the other viscera, the heart only excepted. On

  the other hand, the liver of oviparous quadrupeds and fishes inclines,

  as a rule, to a yellow hue, and there are even some of them in which

  it is entirely of this bad colour, in accordance with the bad

  composition of their bodies generally. Such, for instance, is the case

  in the toad, the tortoise, and other similar animals.

  The spleen, again, varies in different animals. For in those that

  have horns and cloven hoofs, such as the goat, the sheep, and the

  like, it is of a rounded form; excepting when increased size has

  caused some part of it to extend its growth longitudinally, as has

  happened in the case of the ox. On the other hand, it is elongated

  in all polydactylous animals. Such, for instance, is the case in the

  pig, in man, and in the dog. While in animals with solid hoofs it is

  of a form intermediate to these two, being broad in one part, narrow

  in another. Such, for example, is its shape in the horse, the mule,

  and the ass.

  13

  The viscera differ from the flesh not only in the turgid aspect of

  their substance, but also in position; for they lie within the body,

  whereas the flesh is placed on the outside. The explanation of this is

  that these parts partake of the character of blood-vessels, and that

  while the former exist for the sake of the vessels, the latter

  cannot exist without them.

  14

  Below the midriff lies the stomach, placed at the end of the

  oesophagus when there is one, and in immediate contiguity with the

  mouth when the oesophagus is wanting. Continuous with this stomach

  is what is called the gut. These parts are present in all animals, for

  reasons that are self-evident. For it is a matter of necessity that an

  animal shall receive the incoming food; and necessary also that it

  shall discharge the same when its goodness is exhausted. This residual

  matter, again, must not occupy the same place as the yet unconcocted

  nutriment. For as the ingress of food and the discharge of the residue

  occur at distinct periods, so also must they necessarily occur in

  distinct places. Thus there must be one receptacle for the ingoing

  food and another for the useless residue, and between these,

  therefore, a part in which the change from one condition to the

  other may be effected. These, however, are matters which will be

  more suitably set forth when we come to deal with Generation and

  Nutrition. What we have at present to consider are the variations

  presented by the stomach and its subsidiary parts. For neither in size

  nor in shape are these parts uniformly alike in all animals. Thus

  the stomach is single in all such sanguineous and viviparous animals

  as have teeth in front of both jaws. It is single therefore in all the

  polydactylous kinds, such as man, dog, lion, and the rest; in all

  the solid-hoofed animals also, such as horse, mule, ass; and in all

  those which, like the pig, though their hoof is cloven, yet have front

  teeth in both jaws. When, however, an animal is of large size, and

  feeds on substances of so thorny and ligneous a character as to be

  difficult of concoction, it may in consequence have several

  stomachs, as for instance is the case with the camel. A similar

  multiplicity of stomachs exists also in the horned animals; the reason

  being that horn-bearing animals have no front teeth in the upper

  jaw. The camel also, though it has no horns, is yet without upper

  front teeth. The explanation of this is that it is more essential

  for the camel to have a multiple stomach than to have these teeth. Its

  stomach, then, is constructed like that of animals without upper front

  teeth, and, its dental arrangements being such as to match its

  stomach, the teeth in question are wanting. They would indeed be of no

  service. Its food, moreover, being of a thorny character, and its

  tongue necessarily made of a fleshy substance, nature uses the

  earthy matter which is saved from the teeth to give hardness to the

  palate. The camel ruminates like the horned animals, because its

  multiple stomach resembles theirs. For all animals that have horns,

  the sheep for instance, the ox, the goat, the deer, and the like, have

  several stomachs. For since the mouth, owing to its lack of teeth,

  only imperfectly performs its office as regards the food, this

  multiplicity of stomachs is intended to make up for its

  shortcomings; the several cavities receiving the food one from the

  other in succession; the first taking the unreduced substances, the

  second the same when somewhat reduced, the third when reduction is

  complete, and the fourth when the whole has become a smooth pulp. Such

  is the reason why there is this multiplicity of parts and cavities

  in animals with such dentition. The names given to the several

  cavities are the paunch, the honeycomb bag, the manyplies, and the

  reed. How these parts are related to each other, in position and in

  shape, must be looked for in the treatises on Anatomy and the

  Researches concerning Animals.

  Birds also present variations in the part which acts as a

  recipient
of the food; and the reason for these variations is the same

  as in the animals just mentioned. For here again it is because the

  mouth fails to perform its office and fails even more completely-for

  birds have no teeth at all, nor any instrument whatsoever with which

  to comminute or grind down their food-it is, I say, because of this,

  that in some of them what is called the crop precedes the stomach

  and does the work of the mouth; while in others the oesophagus is

  either wide throughout or a part of it bulges just before it enters

  the stomach, so as to form a preparatory store-house for the unreduced

  food; or the stomach itself has a protuberance in some part, or is

  strong and fleshy, so as to be able to store up the food for a

  considerable period and to concoct it, in spite of its not having been

  ground into a pulp. For nature retrieves the inefficiency of the mouth

  by increasing the efficiency and heat of the stomach. Other birds

  there are, such, namely, as have long legs and live in marshes, that

  have none of these provisions, but merely an elongated oesophagus. The

  explanation of this is to be found in the moist character of their

  food. For all these birds feed on substances easy of reduction, and

  their food being moist and not requiring much concoction, their

  digestive cavities are of a corresponding character.

  Fishes are provided with teeth, which in almost all of them are of

  the sharp interfitting kind. For there is but one small section in

  which it is otherwise. Of these the fish called Scarus (Parrot-fish)

  is an example. And this is probably the reason why this fish

  apparently ruminates, though no other fishes do so. For those horned

  animals that have no front teeth in the upper jaw also ruminate.

  In fishes the teeth are all sharp; so that these animals can

  divide their food, though imperfectly. For it is impossible for a fish

  to linger or spend time in the act of mastication, and therefore

  they have no teeth that are flat or suitable for grinding; for such

  teeth would be to no purpose. The oesophagus again in some fishes is

  entirely wanting, and in the rest is but short. In order, however,