No More Learning

The 'womb' is a part peculiar to the female; and the 'penis' is
peculiar to the male. This latter organ is external and situated at
the extremity of the trunk; it is composed of two separate parts: of
which the extreme part is fleshy, does not alter in size, and is
called the glans; and round about it is a skin devoid of any
specific title, which integument if it be cut asunder never grows
together again, any more than does the jaw or the eyelid. And the
connexion between the latter and the glans is called the frenum. The
remaining part of the penis is composed of gristle; it is easily
susceptible of enlargement; and it protrudes and recedes in the
reverse directions to what is observable in the identical organ in
cats. Underneath the penis are two 'testicles', and the integument
of these is a skin that is termed the 'scrotum'.

Testicles are not identical with flesh, and are not altogether
diverse from it. But by and by we shall treat in an exhaustive way
regarding all such parts.

14

The privy part of the female is in character opposite to that of
the male. In other words, the part under the pubes is hollow or
receding, and not, like the male organ, protruding. Further, there
is an 'urethra' outside the womb; which organ serves as a passage
for the sperm of the male, and as an outlet for liquid excretion to
both sexes).

The part common to the neck and chest is the 'throat'; the
'armpit' is common to side, arm, and shoulder; and the 'groin' is
common to thigh and abdomen. The part inside the thigh and buttocks is
the 'perineum', and the part outside the thigh and buttocks is the
'hypoglutis'.

The front parts of the trunk have now been enumerated.

The part behind the chest is termed the 'back'.

15

Parts of the back are a pair of 'shoulderblades', the
'back-bone', and, underneath on a level with the belly in the trunk,
the 'loins'. Common to the upper and lower part of the trunk are the
'ribs', eight on either side, for as to the so-called seven-ribbed
Ligyans we have not received any trustworthy evidence.

Man, then, has an upper and a lower part, a front and a back
part, a right and a left side. Now the right and the left side are
pretty well alike in their parts and identical throughout, except that
the left side is the weaker of the two; but the back parts do not
resemble the front ones, neither do the lower ones the upper: only
that these upper and lower parts may be said to resemble one another
thus far, that, if the face be plump or meagre, the abdomen is plump
or meagre to correspond; and that the legs correspond to the arms, and
where the upper arm is short the thigh is usually short also, and
where the feet are small the hands are small correspondingly.

Of the limbs, one set, forming a pair, is 'arms'. To the arm
belong the 'shoulder', 'upper-arm', 'elbow', 'fore-arm', and 'hand'.
To the hand belong the 'palm', and the five 'fingers'. The part of the
finger that bends is termed 'knuckle', the part that is inflexible
is termed the 'phalanx'. The big finger or thumb is single-jointed,
the other fingers are double jointed. The bending both of the arm
and of the finger takes place from without inwards in all cases; and
the arm bends at the elbow. The inner part of the hand is termed the
palm', and is fleshy and divided by joints or lines: in the case of
long-lived people by one or two extending right across, in the case of
the short-lived by two, not so extending. The joint between hand and
arm is termed the 'wrist'. The outside or back of the hand is
sinewy, and has no specific designation.

There is another duplicate limb, the 'leg'. Of this limb the
double-knobbed part is termed the 'thigh-bone', the sliding part of
the 'kneecap', the double-boned part the 'leg'; the front part of this
latter is termed the 'shin', and the part behind it the 'calf',
wherein the flesh is sinewy and venous, in some cases drawn upwards
towards the hollow behind the knee, as in the case of people with
large hips, and in other cases drawn downwards. The lower extremity of
the shin is the 'ankle', duplicate in either leg. The part of the limb
that contains a multiplicity of bones is the 'foot'. The hinder part
of the foot is the 'heel'; at the front of it the divided part
consists of 'toes', five in number; the fleshy part underneath is
the 'ball'; the upper part or back of the foot is sinewy and has no
particular appellation; of the toe, one portion is the 'nail' and
another the 'joint', and the nail is in all cases at the extremity;
and toes are without exception single jointed. Men that have the
inside or sole of the foot clumsy and not arched, that is, that walk
resting on the entire under-surface of their feet, are prone to
roguery. The joint common to thigh and shin is the 'knee'.

These, then, are the parts common to the male and the female sex.
The relative position of the parts as to up and down, or to front
and back, or to right and left, all this as regards externals might
safely be left to mere ordinary perception. But for all that, we
must treat of them for the same reason as the one previously brought
forward; that is to say, we must refer to them in order that a due and
regular sequence may be observed in our exposition, and in order
that by the enumeration of these obvious facts due attention may be
subsequently given to those parts in men and other animals that are
diverse in any way from one another.

In man, above all other animals, the terms 'upper' and 'lower'
are used in harmony with their natural positions; for in him, upper
and lower have the same meaning as when they are applied to the
universe as a whole. In like manner the terms, 'in front', 'behind',
'right' and 'left', are used in accordance with their natural sense.
But in regard to other animals, in some cases these distinctions do
not exist, and in others they do so, but in a vague way. For instance,
the head with all animals is up and above in respect to their
bodies; but man alone, as has been said, has, in maturity, this part
uppermost in respect to the material universe.

Next after the head comes the neck, and then the chest and the
back: the one in front and the other behind. Next after these come the
belly, the loins, the sexual parts, and the haunches; then the thigh
and shin; and, lastly, the feet.

The legs bend frontwards, in the direction of actual progression,
and frontwards also lies that part of the foot which is the most
effective of motion, and the flexure of that part; but the heel lies
at the back, and the anklebones lie laterally, earwise. The arms are
situated to right and left, and bend inwards: so that the
convexities formed by bent arms and legs are practically face to
face with one another in the case of man.

As for the senses and for the organs of sensation, the eyes,
the nostrils, and the tongue, all alike are situated frontwards; the
sense of hearing, and the organ of hearing, the ear, is situated
sideways, on the same horizontal plane with the eyes. The eyes in
man are, in proportion to his size, nearer to one another than in
any other animal.

Of the senses man has the sense of touch more refined than any
animal, and so also, but in less degree, the sense of taste; in the
development of the other senses he is surpassed by a great number of
animals.

16

The parts, then, that are externally visible are arranged in the
way above stated, and as a rule have their special designations, and
from use and wont are known familiarly to all; but this is not the
case with the inner parts. For the fact is that the inner parts of man
are to a very great extent unknown, and the consequence is that we
must have recourse to an examination of the inner parts of other
animals whose nature in any way resembles that of man.

In the first place then, the brain lies in the front part of the
head. And this holds alike with all animals possessed of a brain;
and all blooded animals are possessed thereof, and, by the way,
molluscs as well. But, taking size for size of animal, the largest
brain, and the moistest, is that of man. Two membranes enclose it: the
stronger one near the bone of the skull; the inner one, round the
brain itself, is finer. The brain in all cases is bilateral. Behind
this, right at the back, comes what is termed the 'cerebellum',
differing in form from the brain as we may both feel and see.

The back of the head is with all animals empty and hollow,
whatever be its size in the different animals. For some creatures have
big heads while the face below is small in proportion, as is the
case with round-faced animals; some have little heads and long jaws,
as is the case, without exception, among animals of the
mane-and-tail species.

The brain in all animals is bloodless, devoid of veins, and
naturally cold to the touch; in the great majority of animals it has a
small hollow in its centre. The brain-caul around it is reticulated
with veins; and this brain-caul is that skin-like membrane which
closely surrounds the brain. Above the brain is the thinnest and
weakest bone of the head, which is termed or 'sinciput'.

From the eye there go three ducts to the brain: the largest and
the medium-sized to the cerebellum, the least to the brain itself; and
the least is the one situated nearest to the nostril. The two
largest ones, then, run side by side and do not meet; the medium-sized
ones meet-and this is particularly visible in fishes,-for they lie
nearer than the large ones to the brain; the smallest pair are the
most widely separate from one another, and do not meet.

Inside the neck is what is termed the oesophagus (whose other
name is derived oesophagus from its length and narrowness), and the
windpipe. The windpipe is situated in front of the oesophagus in all
animals that have a windpipe, and all animals have one that are
furnished with lungs. The windpipe is made up of gristle, is sparingly
supplied with blood, and is streaked all round with numerous minute
veins; it is situated, in its upper part, near the mouth, below the
aperture formed by the nostrils into the mouth-an aperture through
which, when men, in drinking, inhale any of the liquid, this liquid
finds its way out through the nostrils. In betwixt the two openings
comes the so-called epiglottis, an organ capable of being drawn over
and covering the orifice of the windpipe communicating with the mouth;
the end of the tongue is attached to the epiglottis. In the other
direction the windpipe extends to the interval between the lungs,
and hereupon bifurcates into each of the two divisions of the lung;
for the lung in all animals possessed of the organ has a tendency to
be double. In viviparous animals, however, the duplication is not so
plainly discernible as in other species, and the duplication is
least discernible in man. And in man the organ is not split into
many parts, as is the case with some vivipara, neither is it smooth,
but its surface is uneven.

In the case of the ovipara, such as birds and oviparous
quadrupeds, the two parts of the organ are separated to a distance
from one another, so that the creatures appear to be furnished with
a pair of lungs; and from the windpipe, itself single, there branch
off two separate parts extending to each of the two divisions of the
lung. It is attached also to the great vein and to what is
designated the 'aorta'. When the windpipe is charged with air, the air
passes on to the hollow parts of the lung. These parts have divisions,
composed of gristle, which meet at an acute angle; from the
divisions run passages through the entire lung, giving off smaller and
smaller ramifications. The heart also is attached to the windpipe,
by connexions of fat, gristle, and sinew; and at the point of juncture
there is a hollow. When the windpipe is charged with air, the entrance
of the air into the heart, though imperceptible in some animals, is
perceptible enough in the larger ones. Such are the properties of
the windpipe, and it takes in and throws out air only, and takes in
nothing else either dry or liquid, or else it causes you pain until
you shall have coughed up whatever may have gone down.

The oesophagus communicates at the top with the mouth, close to
the windpipe, and is attached to the backbone and the windpipe by
membranous ligaments, and at last finds its way through the midriff
into the belly. It is composed of flesh-like substance, and is elastic
both lengthways and breadthways.

The stomach of man resembles that of a dog; for it is not much
bigger than the bowel, but is somewhat like a bowel of more than usual
width; then comes the bowel, single, convoluted, moderately wide.
The lower part of the gut is like that of a pig; for it is broad,
and the part from it to the buttocks is thick and short. The caul,
or great omentum, is attached to the middle of the stomach, and
consists of a fatty membrane, as is the case with all other animals
whose stomachs are single and which have teeth in both jaws.

The mesentery is over the bowels; this also is membranous and
broad, and turns to fat. It is attached to the great vein and the
aorta, and there run through it a number of veins closely packed
together, extending towards the region of the bowels, beginning
above and ending below.

So much for the properties of the oesophagus, the windpipe, and
the stomach.

17

The heart has three cavities, and is situated above the lung at
the division of the windpipe, and is provided with a fatty and thick
membrane where it fastens on to the great vein and the aorta. It
lies with its tapering portion upon the aorta, and this portion is
similarly situated in relation to the chest in all animals that have a
chest. In all animals alike, in those that have a chest and in those
that have none, the apex of the heart points forwards, although this
fact might possibly escape notice by a change of position under
dissection. The rounded end of the heart is at the top. The apex is to
a great extent fleshy and close in texture, and in the cavities of the
heart are sinews. As a rule the heart is situated in the middle of the
chest in animals that have a chest, and in man it is situated a little
to the left-hand side, leaning a little way from the division of the
breasts towards the left breast in the upper part of the chest.

The heart is not large, and in its general shape it is not
elongated; in fact, it is somewhat round in form: only, be it
remembered, it is sharp-pointed at the bottom. It has three
cavities, as has been said: the right-hand one the largest of the
three, the left-hand one the least, and the middle one intermediate in
size. All these cavities, even the two small ones, are connected by
passages with the lung, and this fact is rendered quite plain in one
of the cavities. And below, at the point of attachment, in the largest
cavity there is a connexion with the great vein (near which the
mesentery lies); and in the middle one there is a connexion with the
aorta.

Canals lead from the heart into the lung, and branch off just
as the windpipe does, running all over the lung parallel with the
passages from the windpipe. The canals from the heart are uppermost;
and there is no common passage, but the passages through their
having a common wall receive the breath and pass it on to the heart;
and one of the passages conveys it to the right cavity, and the
other to the left.

With regard to the great vein and the aorta we shall, by and
by, treat of them together in a discussion devoted to them and to them
alone. In all animals that are furnished with a lung, and that are
both internally and externally viviparous, the lung is of all organs
the most richly supplied with blood; for the lung is throughout spongy
in texture, and along by every single pore in it go branches from
the great vein. Those who imagine it to be empty are altogether
mistaken; and they are led into their error by their observation of
lungs removed from animals under dissection, out of which organs the
blood had all escaped immediately after death.

Of the other internal organs the heart alone contains blood.
And the lung has blood not in itself but in its veins, but the heart
has blood in itself; for in each of its three cavities it has blood,
but the thinnest blood is what it has in its central cavity.

Under the lung comes the thoracic diaphragm or midriff,
attached to the ribs, the hypochondria and the backbone, with a thin
membrane in the middle of it. It has veins running through it; and the
diaphragm in the case of man is thicker in proportion to the size of
his frame than in other animals.

Under the diaphragm on the right-hand side lies the 'liver',
and on the left-hand side the 'spleen', alike in all animals that
are provided with these organs in an ordinary and not preternatural
way; for, be it observed, in some quadrupeds these organs have been
found in a transposed position. These organs are connected with the
stomach by the caul.

To outward view the spleen of man is narrow and long,
resembling the self-same organ in the pig. The liver in the great
majority of animals is not provided with a 'gall-bladder'; but the
latter is present in some. The liver of a man is round-shaped, and
resembles the same organ in the ox. And, by the way, the absence above
referred to of a gall-bladder is at times met with in the practice
of augury. For instance, in a certain district of the Chalcidic
settlement in Euboea the sheep are devoid of gall-bladders; and in
Naxos nearly all the quadrupeds have one so large that foreigners when
they offer sacrifice with such victims are bewildered with fright,
under the impression that the phenomenon is not due to natural causes,
but bodes some mischief to the individual offerers of the sacrifice.

Again, the liver is attached to the great vein, but it has no
communication with the aorta; for the vein that goes off from the
great vein goes right through the liver, at a point where are the
so-called 'portals' of the liver. The spleen also is connected only
with the great vein, for a vein extends to the spleen off from it.

After these organs come the 'kidneys', and these are placed close
to the backbone, and resemble in character the same organ in kine.
In all animals that are provided with this organ, the right kidney
is situated higher up than the other. It has also less fatty substance
than the left-hand one and is less moist. And this phenomenon also
is observable in all the other animals alike.

Furthermore, passages or ducts lead into the kidneys both from
the great vein and from the aorta, only not into the cavity. For, by
the way, there is a cavity in the middle of the kidney, bigger in some
creatures and less in others; but there is none in the case of the
seal. This latter animal has kidneys resembling in shape the identical
organ in kine, but in its case the organs are more solid than in any
other known creature. The ducts that lead into the kidneys lose
themselves in the substance of the kidneys themselves; and the proof
that they extend no farther rests on the fact that they contain no
blood, nor is any clot found therein. The kidneys, however, have, as
has been said, a small cavity. From this cavity in the kidney there
lead two considerable ducts or ureters into the bladder; and others
spring from the aorta, strong and continuous. And to the middle of
each of the two kidneys is attached a hollow sinewy vein, stretching
right along the spine through the narrows; by and by these veins are
lost in either loin, and again become visible extending to the
flank. And these off-branchings of the veins terminate in the bladder.
For the bladder lies at the extremity, and is held in position by
the ducts stretching from the kidneys, along the stalk that extends to
the urethra; and pretty well all round it is fastened by fine sinewy
membranes, that resemble to some extent the thoracic diaphragm. The
bladder in man is, proportionately to his size, tolerably large.

To the stalk of the bladder the private part is attached, the
external orifices coalescing; but a little lower down, one of the
openings communicates with the testicles and the other with the
bladder. The penis is gristly and sinewy in its texture. With it are
connected the testicles in male animals, and the properties of these
organs we shall discuss in our general account of the said organ.

All these organs are similar in the female; for there is no
difference in regard to the internal organs, except in respect to
the womb, and with reference to the appearance of this organ I must
refer the reader to diagrams in my 'Anatomy'. The womb, however, is
situated over the bowel, and the bladder lies over the womb. But we
must treat by and by in our pages of the womb of all female animals
viewed generally. For the wombs of all female animals are not
identical, neither do their local dispositions coincide.

These are the organs, internal and external, of man, and such
is their nature and such their local disposition.

Book II

1

With regard to animals in general, some parts or organs are
common to all, as has been said, and some are common only to
particular genera; the parts, moreover, are identical with or
different from one another on the lines already repeatedly laid
down. For as a general rule all animals that are generically
distinct have the majority of their parts or organs different in
form or species; and some of them they have only analogically
similar and diverse in kind or genus, while they have others that
are alike in kind but specifically diverse; and many parts or organs
exist in some animals, but not in others.

For instance, viviparous quadrupeds have all a head and a neck,
and all the parts or organs of the head, but they differ each from
other in the shapes of the parts. The lion has its neck composed of
one single bone instead of vertebrae; but, when dissected, the
animal is found in all internal characters to resemble the dog.

The quadrupedal vivipara instead of arms have forelegs. This is
true of all quadrupeds, but such of them as have toes have,
practically speaking, organs analogous to hands; at all events, they
use these fore-limbs for many purposes as hands. And they have the
limbs on the left-hand side less distinct from those on the right than
man.

The fore-limbs then serve more or less the purpose of hands in
quadrupeds, with the exception of the elephant. This latter animal has
its toes somewhat indistinctly defined, and its front legs are much
bigger than its hinder ones; it is five-toed, and has short ankles
to its hind feet. But it has a nose such in properties and such in
size as to allow of its using the same for a hand. For it eats and
drinks by lifting up its food with the aid of this organ into its
mouth, and with the same organ it lifts up articles to the driver on
its back; with this organ it can pluck up trees by the roots, and when
walking through water it spouts the water up by means of it; and
this organ is capable of being crooked or coiled at the tip, but not
of flexing like a joint, for it is composed of gristle.

Of all animals man alone can learn to make equal use of both
hands.

All animals have a part analogous to the chest in man, but not
similar to his; for the chest in man is broad, but that of all other
animals is narrow. Moreover, no other animal but man has breasts in
front; the elephant, certainly, has two breasts, not however in the
chest, but near it.

Moreover, also, animals have the flexions of their fore and
hind limbs in directions opposite to one another, and in directions
the reverse of those observed in the arms and legs of man; with the
exception of the elephant. In other words, with the viviparous
quadrupeds the front legs bend forwards and the hind ones backwards,
and the concavities of the two pairs of limbs thus face one another.

The elephant does not sleep standing, as some were wont to
assert, but it bends its legs and settles down; only that in
consequence of its weight it cannot bend its leg on both sides
simultaneously, but falls into a recumbent position on one side or the
other, and in this position it goes to sleep. And it bends its hind
legs just as a man bends his legs.

In the case of the ovipara, as the crocodile and the lizard and
the like, both pairs of legs, fore and hind, bend forwards, with a
slight swerve on one side. The flexion is similar in the case of the
multipeds; only that the legs in between the extreme ends always
move in a manner intermediate between that of those in front and those
behind, and accordingly bend sideways rather than backwards or
forwards. But man bends his arms and his legs towards the same
point, and therefore in opposite ways: that is to say, he bends his
arms backwards, with just a slight inclination inwards, and his legs
frontwards. No animal bends both its fore-limbs and hind-limbs
backwards; but in the case of all animals the flexion of the shoulders
is in the opposite direction to that of the elbows or the joints of
the forelegs, and the flexure in the hips to that of the knees of
the hind-legs: so that since man differs from other animals in
flexion, those animals that possess such parts as these move them
contrariwise to man.

Birds have the flexions of their limbs like those of the
quadrupeds; for, although bipeds, they bend their legs backwards,
and instead of arms or front legs have wings which bend frontwards.

The seal is a kind of imperfect or crippled quadruped; for just
behind the shoulder-blade its front feet are placed, resembling hands,
like the front paws of the bear; for they are furnished with five
toes, and each of the toes has three flexions and a nail of
inconsiderable size. The hind feet are also furnished with five
toes; in their flexions and nails they resemble the front feet, and in
shape they resemble a fish's tail.

The movements of animals, quadruped and multiped, are crosswise,
or in diagonals, and their equilibrium in standing posture is
maintained crosswise; and it is always the limb on the right-hand side
that is the first to move. The lion, however, and the two species of
camels, both the Bactrian and the Arabian, progress by an amble; and
the action so called is when the animal never overpasses the right
with the left, but always follows close upon it.

Whatever parts men have in front, these parts quadrupeds have
below, in or on the belly; and whatever parts men have behind, these
parts quadrupeds have above on their backs. Most quadrupeds have a
tail; for even the seal has a tiny one resembling that of the stag.
Regarding the tails of the pithecoids we must give their distinctive
properties by and by animal

All viviparous quadrupeds are hair-coated, whereas man has only a
few short hairs excepting on the head, but, so far as the head is
concerned, he is hairier than any other animal. Further, of
hair-coated animals, the back is hairier than the belly, which
latter is either comparatively void of hair or smooth and void of hair
altogether. With man the reverse is the case.

Man also has upper and lower eyelashes, and hair under the
armpits and on the pubes. No other animal has hair in either of
these localities, or has an under eyelash; though in the case of
some animals a few straggling hairs grow under the eyelid.

Of hair-coated quadrupeds some are hairy all over the body, as
the pig, the bear, and the dog; others are especially hairy on the
neck and all round about it, as is the case with animals that have a
shaggy mane, such as the lion; others again are especially hairy on
the upper surface of the neck from the head as far as the withers,
namely, such as have a crested mane, as in the case with the horse,
the mule, and, among the undomesticated horned animals, the bison.

The so-called hippelaphus also has a mane on its withers, and the
animal called pardion, in either case a thin mane extending from the
head to the withers; the hippelaphus has, exceptionally, a beard by
the larynx. Both these animals have horns and are cloven-footed; the
female, however, of the hippelaphus has no horns. This latter animal
resembles the stag in size; it is found in the territory of the
Arachotae, where the wild cattle also are found. Wild cattle differ
from their domesticated congeners just as the wild boar differs from
the domesticated one. That is to say they are black, strong looking,
with a hook-nosed muzzle, and with horns lying more over the back. The
horns of the hippelaphus resemble those of the gazelle.

The elephant, by the way, is the least hairy of all quadrupeds.
With animals, as a general rule, the tail corresponds with the body as
regards thickness or thinness of hair-coating; that is, with animals
that have long tails, for some creatures have tails of altogether
insignificant size.

Camels have an exceptional organ wherein they differ from all
other animals, and that is the so-called 'hump' on their back. The
Bactrian camel differs from the Arabian; for the former has two
humps and the latter only one, though it has, by the way, a kind of
a hump below like the one above, on which, when it kneels, the
weight of the whole body rests. The camel has four teats like the cow,
a tail like that of an ass, and the privy parts of the male are
directed backwards. It has one knee in each leg, and the flexures of
the limb are not manifold, as some say, although they appear to be
so from the constricted shape of the region of the belly. It has a
huckle-bone like that of kine, but meagre and small in proportion to
its bulk. It is cloven-footed, and has not got teeth in both jaws; and
it is cloven footed in the following way: at the back there is a
slight cleft extending as far up as the second joint of the toes;
and in front there are small hooves on the tip of the first joint of
the toes; and a sort of web passes across the cleft, as in geese.
The foot is fleshy underneath, like that of the bear; so that, when
the animal goes to war, they protect its feet, when they get sore,
with sandals.

The legs of all quadrupeds are bony, sinewy, and fleshless; and
in point of fact such is the case with all animals that are
furnished with feet, with the exception of man. They are also
unfurnished with buttocks; and this last point is plain in an especial
degree in birds. It is the reverse with man; for there is scarcely any
part of the body in which man is so fleshy as in the buttock, the
thigh, and the calf; for the part of the leg called gastroenemia or is
fleshy.

Of blooded and viviparous quadrupeds some have the foot cloven
into many parts, as is the case with the hands and feet of man (for
some animals, by the way, are many-toed, as the lion, the dog, and the
pard); others have feet cloven in twain, and instead of nails have
hooves, as the sheep, the goat, the deer, and the hippopotamus; others
are uncloven of foot, such for instance as the solid-hooved animals,
the horse and the mule. Swine are either cloven-footed or
uncloven-footed; for there are in Illyria and in Paeonia and elsewhere
solid-hooved swine. The cloven-footed animals have two clefts
behind; in the solid-hooved this part is continuous and undivided.

Furthermore, of animals some are horned, and some are not so.
The great majority of the horned animals are cloven-footed, as the ox,
the stag, the goat; and a solid-hooved animal with a pair of horns has
never yet been met with. But a few animals are known to be
singled-horned and single-hooved, as the Indian ass; and one, to wit
the oryx, is single horned and cloven-hooved.

Of all solid-hooved animals the Indian ass alone has an astragalus
or huckle-bone; for the pig, as was said above, is either solid-hooved
or cloven-footed, and consequently has no well-formed huckle-bone.
Of the cloven footed many are provided with a huckle-bone. Of the
many-fingered or many-toed, no single one has been observed to have
a huckle-bone, none of the others any more than man. The lynx,
however, has something like a hemiastragal, and the lion something
resembling the sculptor's 'labyrinth'. All the animals that have a
huckle-bone have it in the hinder legs. They have also the bone placed
straight up in the joint; the upper part, outside; the lower part,
inside; the sides called Coa turned towards one another, the sides
called Chia outside, and the keraiae or 'horns' on the top.
This,
then, is the position of the hucklebone in the case of all animals
provided with the part.

Some animals are, at one and the same time, furnished with a mane
and furnished also with a pair of horns bent in towards one another,
as is the bison (or aurochs), which is found in Paeonia and Maedica.
But all animals that are horned are quadrupedal, except in cases where
a creature is said metaphorically, or by a figure of speech, to have
horns; just as the Egyptians describe the serpents found in the
neighbourhood of Thebes, while in point of fact the creatures have
merely protuberances on the head sufficiently large to suggest such an
epithet.

Of horned animals the deer alone has a horn, or antler, hard
and solid throughout. The horns of other animals are hollow for a
certain distance, and solid towards the extremity. The hollow part
is derived from the skin, but the core round which this is wrapped-the
hard part-is derived from the bones; as is the case with the horns
of oxen. The deer is the only animal that sheds its horns, and it does
so annually, after reaching the age of two years, and again renews
them. All other animals retain their horns permanently, unless the
horns be damaged by accident.

Again, with regard to the breasts and the generative organs,
animals differ widely from one another and from man. For instance, the
breasts of some animals are situated in front, either in the chest
or near to it, and there are in such cases two breasts and two
teats, as is the case with man and the elephant, as previously stated.
For the elephant has two breasts in the region of the axillae; and the
female elephant has two breasts insignificant in size and in no way
proportionate to the bulk of the entire frame, in fact, so
insignificant as to be invisible in a sideways view; the males also
have breasts, like the females, exceedingly small. The she-bear has
four breasts. Some animals have two breasts, but situated near the
thighs, and teats, likewise two in number, as the sheep; others have
four teats, as the cow. Some have breasts neither in the chest nor
at the thighs, but in the belly, as the dog and pig; and they have a
considerable number of breasts or dugs, but not all of equal size.
Thus the shepard has four dugs in the belly, the lioness two, and
others more. The she-camel, also, has two dugs and four teats, like
the cow. Of solid-hooved animals the males have no dugs, excepting
in the case of males that take after the mother, which phenomenon is
observable in horses.

Of male animals the genitals of some are external, as is the case
with man, the horse, and most other creatures; some are internal, as
with the dolphin. With those that have the organ externally placed,
the organ in some cases is situated in front, as in the cases
already mentioned, and of these some have the organ detached, both
penis and testicles, as man; others have penis and testicles closely
attached to the belly, some more closely, some less; for this organ is
not detached in the wild boar nor in the horse.

The penis of the elephant resembles that of the horse; compared
with the size of the animal it is disproportionately small; the
testicles are not visible, but are concealed inside in the vicinity of
the kidneys; and for this reason the male speedily gives over in the
act of intercourse. The genitals of the female are situated where
the udder is in sheep; when she is in heat, she draws the organ back
and exposes it externally, to facilitate the act of intercourse for
the male; and the organ opens out to a considerable extent.

With most animals the genitals have the position above
assigned; but some animals discharge their urine backwards, as the
lynx, the lion, the camel, and the hare. Male animals differ from
one another, as has been said, in this particular, but all female
animals are retromingent: even the female elephant like other animals,
though she has the privy part below the thighs.

In the male organ itself there is a great diversity. For in some
cases the organ is composed of flesh and gristle, as in man; in such
cases, the fleshy part does not become inflated, but the gristly
part is subject to enlargement. In other cases, the organ is
composed of fibrous tissue, as with the camel and the deer; in other
cases it is bony, as with the fox, the wolf, the marten, and the
weasel; for this organ in the weasel has a bone.

When man has arrived at maturity, his upper part is smaller
than the lower one, but with all other blooded animals the reverse
holds good. By the 'upper' part we mean all extending from the head
down to the parts used for excretion of residuum, and by the 'lower'
part else. With animals that have feet the hind legs are to be rated
as the lower part in our comparison of magnitudes, and with animals
devoid of feet, the tail, and the like.

When animals arrive at maturity, their properties are as above
stated; but they differ greatly from one another in their growth
towards maturity. For instance, man, when young, has his upper part
larger than the lower, but in course of growth he comes to reverse
this condition; and it is owing to this circumstance that-an
exceptional instance, by the way-he does not progress in early life as
he does at maturity, but in infancy creeps on all fours; but some
animals, in growth, retain the relative proportion of the parts, as
the dog. Some animals at first have the upper part smaller and the
lower part larger, and in course of growth the upper part gets to be
the larger, as is the case with the bushy-tailed animals such as the
horse; for in their case there is never, subsequently to birth, any
increase in the part extending from the hoof to the haunch.

Again, in respect to the teeth, animals differ greatly both
from one another and from man. All animals that are quadrupedal,
blooded and viviparous, are furnished with teeth; but, to begin
with, some are double-toothed (or fully furnished with teeth in both
jaws), and some are not. For instance, horned quadrupeds are not
double-toothed; for they have not got the front teeth in the upper
jaw; and some hornless animals, also, are not double toothed, as the
camel. Some animals have tusks, like the boar, and some have not.
Further, some animals are saw-toothed, such as the lion, the pard, and
the dog; and some have teeth that do not interlock but have flat
opposing crowns, as the horse and the ox; and by 'saw-toothed' we mean
such animals as interlock the sharp-pointed teeth in one jaw between
the sharp-pointed ones in the other. No animal is there that possesses
both tusks and horns, nor yet do either of these structures exist in
any animal possessed of 'saw-teeth'. The front teeth are usually
sharp, and the back ones blunt. The seal is saw-toothed throughout,
inasmuch as he is a sort of link with the class of fishes; for
fishes are almost all saw-toothed.

No animal of these genera is provided with double rows of
teeth. There is, however, an animal of the sort, if we are to
believe Ctesias. He assures us that the Indian wild beast called the
'martichoras' has a triple row of teeth in both upper and lower jaw;
that it is as big as a lion and equally hairy, and that its feet
resemble those of the lion; that it resembles man in its face and
ears; that its eyes are blue, and its colour vermilion; that its
tail is like that of the land-scorpion; that it has a sting in the
tail, and has the faculty of shooting off arrow-wise the spines that
are attached to the tail; that the sound of its voice is a something
between the sound of a pan-pipe and that of a trumpet; that it can run
as swiftly as deer, and that it is savage and a man-eater.

Man sheds his teeth, and so do other animals, as the horse, the
mule, and the ass. And man sheds his front teeth; but there is no
instance of an animal that sheds its molars. The pig sheds none of its
teeth at all.

2

With regard to dogs some doubts are entertained, as some contend
that they shed no teeth whatever, and others that they shed the
canines, but those alone; the fact being, that they do shed their
teeth like man, but that the circumstance escapes observation, owing
to the fact that they never shed them until equivalent teeth have
grown within the gums to take the place of the shed ones. We shall
be justified in supposing that the case is similar with wild beasts in
general; for they are said to shed their canines only. Dogs can be
distinguished from one another, the young from the old, by their
teeth; for the teeth in young dogs are white and sharp-pointed; in old
dogs, black and blunt.

3

In this particular, the horse differs entirely from animals in
general: for, generally speaking, as animals grow older their teeth
get blacker, but the horse's teeth grow whiter with age.

The so-called 'canines' come in between the sharp teeth and the
broad or blunt ones, partaking of the form of both kinds; for they are
broad at the base and sharp at the tip.

Males have more teeth than females in the case of men, sheep,
goats, and swine; in the case of other animals observations have not
yet been made: but the more teeth they have the more long-lived are
they, as a rule, while those are short-lived in proportion that have
teeth fewer in number and thinly set.

4

The last teeth to come in man are molars called 'wisdom-teeth',
which come at the age of twenty years, in the case of both sexes.
Cases have been known in women upwards. of eighty years old where at
the very close of life the wisdom-teeth have come up, causing great
pain in their coming; and cases have been known of the like phenomenon
in men too. This happens, when it does happen, in the case of people
where the wisdom-teeth have not come up in early years.

5

The elephant has four teeth on either side, by which it munches
its food, grinding it like so much barley-meal, and, quite apart
from these, it has its great teeth, or tusks, two in number. In the
male these tusks are comparatively large and curved upwards; in the
female, they are comparatively small and point in the opposite
direction; that is, they look downwards towards the ground. The
elephant is furnished with teeth at birth, but the tusks are not
then visible.

6

The tongue of the elephant is exceedingly small, and situated
far back in the mouth, so that it is difficult to get a sight of it.

7

Furthermore, animals differ from one another in the relative size
of their mouths. In some animals the mouth opens wide, as is the
case with the dog, the lion, and with all the saw-toothed animals;
other animals have small mouths, as man; and others have mouths of
medium capacity, as the pig and his congeners.

(The Egyptian hippopotamus has a mane like a horse, is
cloven-footed like an ox, and is snub-nosed. It has a huckle-bone like
cloven-footed animals, and tusks just visible; it has the tail of a
pig, the neigh of a horse, and the dimensions of an ass. The hide is
so thick that spears are made out of it. In its internal organs it
resembles the horse and the ass. )

8

Some animals share the properties of man and the quadrupeds, as
the ape, the monkey, and the baboon. The monkey is a tailed ape. The
baboon resembles the ape in form, only that it is bigger and stronger,
more like a dog in face, and is more savage in its habits, and its
teeth are more dog-like and more powerful.

Apes are hairy on the back in keeping with their quadrupedal
nature, and hairy on the belly in keeping with their human form-for,
as was said above, this characteristic is reversed in man and the
quadruped-only that the hair is coarse, so that the ape is thickly
coated both on the belly and on the back. Its face resembles that of
man in many respects; in other words, it has similar nostrils and
ears, and teeth like those of man, both front teeth and molars.
Further, whereas quadrupeds in general are not furnished with lashes
on one of the two eyelids, this creature has them on both, only very
thinly set, especially the under ones; in fact they are very
insignificant indeed. And we must bear in mind that all other
quadrupeds have no under eyelash at all.

The ape has also in its chest two teats upon poorly developed
breasts. It has also arms like man, only covered with hair, and it
bends these legs like man, with the convexities of both limbs facing
one another. In addition, it has hands and fingers and nails like man,
only that all these parts are somewhat more beast-like in
appearance. Its feet are exceptional in kind. That is, they are like
large hands, and the toes are like fingers, with the middle one the
longest of all, and the under part of the foot is like a hand except
for its length, and stretches out towards the extremities like the
palm of the hand; and this palm at the after end is unusually hard,
and in a clumsy obscure kind of way resembles a heel. The creature
uses its feet either as hands or feet, and doubles them up as one
doubles a fist. Its upper-arm and thigh are short in proportion to the
forearm and the shin. It has no projecting navel, but only a
hardness in the ordinary locality of the navel. Its upper part is much
larger than its lower part, as is the case with quadrupeds; in fact,
the proportion of the former to the latter is about as five to
three. Owing to this circumstance and to the fact that its feet
resemble hands and are composed in a manner of hand and of foot: of
foot in the heel extremity, of the hand in all else-for even the
toes have what is called a 'palm':-for these reasons the animal is
oftener to be found on all fours than upright. It has neither hips,
inasmuch as it is a quadruped, nor yet a tail, inasmuch as it is a
biped, except nor yet a tal by the way that it has a tail as small
as small can be, just a sort of indication of a tail. The genitals
of the female resemble those of the female in the human species; those
of the male are more like those of a dog than are those of a man.

9

The monkey, as has been observed, is furnished with a tail. In
all such creatures the internal organs are found under dissection to
correspond to those of man.

So much then for the properties of the organs of such animals
as bring forth their young into the world alive.

10

Oviparous and blooded quadrupeds-and, by the way, no terrestrial
blooded animal is oviparous unless it is quadrupedal or is devoid of
feet altogether-are furnished with a head, a neck, a back, upper and
under parts, the front legs and hind legs, and the part analogous to
the chest, all as in the case of viviparous quadrupeds, and with a
tail, usually large, in exceptional cases small. And all these
creatures are many-toed, and the several toes are cloven apart.
Furthermore, they all have the ordinary organs of sensation, including
a tongue, with the exception of the Egyptian crocodile.

This latter animal, by the way, resembles certain fishes. For, as
a general rule, fishes have a prickly tongue, not free in its
movements; though there are some fishes that present a smooth
undifferentiated surface where the tongue should be, until you open
their mouths wide and make a close inspection.

Again, oviparous blooded quadrupeds are unprovided with ears, but
possess only the passage for hearing; neither have they breasts, nor a
copulatory organ, nor external testicles, but internal ones only;
neither are they hair coated, but are in all cases covered with
scaly plates. Moreover, they are without exception saw-toothed.

River crocodiles have pigs' eyes, large teeth and tusks, and
strong nails, and an impenetrable skin composed of scaly plates.
They see but poorly under water, but above the surface of it with
remarkable acuteness. As a rule, they pass the day-time on land and
the nighttime in the water; for the temperature of the water is at
night-time more genial than that of the open air.

11

The chameleon resembles the lizard in the general configuration of
its body, but the ribs stretch downwards and meet together under the
belly as is the case with fishes, and the spine sticks up as with
the fish. Its face resembles that of the baboon. Its tail is
exceedingly long, terminates in a sharp point, and is for the most
part coiled up, like a strap of leather. It stands higher off the
ground than the lizard, but the flexure of the legs is the same in
both creatures. Each of its feet is divided into two parts, which bear
the same relation to one another that the thumb and the rest of the
hand bear to one another in man. Each of these parts is for a short
distance divided after a fashion into toes; on the front feet the
inside part is divided into three and the outside into two, on the
hind feet the inside part into two and the outside into three; it
has claws also on these parts resembling those of birds of prey. Its
body is rough all over, like that of the crocodile. Its eyes are
situated in a hollow recess, and are very large and round, and are
enveloped in a skin resembling that which covers the entire body;
and in the middle a slight aperture is left for vision, through
which the animal sees, for it never covers up this aperture with the
cutaneous envelope. It keeps twisting its eyes round and shifting
its line of vision in every direction, and thus contrives to get a
sight of any object that it wants to see. The change in its colour
takes place when it is inflated with air; it is then black, not unlike
the crocodile, or green like the lizard but black-spotted like the
pard. This change of colour takes place over the whole body alike, for
the eyes and the tail come alike under its influence. In its movements
it is very sluggish, like the tortoise. It assumes a greenish hue in
dying, and retains this hue after death. It resembles the lizard in
the position of the oesophagus and the windpipe. It has no flesh
anywhere except a few scraps of flesh on the head and on the jaws
and near to the root of the tail. It has blood only round about the
heart, the eyes, the region above the heart, and in all the veins
extending from these parts; and in all these there is but little blood
after all. The brain is situated a little above the eyes, but
connected with them. When the outer skin is drawn aside from off the
eye, a something is found surrounding the eye, that gleams through
like a thin ring of copper. Membranes extend well nigh over its entire
frame, numerous and strong, and surpassing in respect of number and
relative strength those found in any other animal. After being cut
open along its entire length it continues to breathe for a
considerable time; a very slight motion goes on in the region of the
heart, and, while contraction is especially manifested in the
neighbourhood of the ribs, a similar motion is more or less
discernible over the whole body. It has no spleen visible. It
hibernates, like the lizard.

12

Birds also in some parts resemble the above mentioned animals;
that is to say, they have in all cases a head, a neck, a back, a
belly, and what is analogous to the chest. The bird is remarkable
among animals as having two feet, like man; only, by the way, it bends
them backwards as quadrupeds bend their hind legs, as was noticed
previously. It has neither hands nor front feet, but wings-an
exceptional structure as compared with other animals. Its
haunch-bone is long, like a thigh, and is attached to the body as
far as the middle of the belly; so like to a thigh is it that when
viewed separately it looks like a real one, while the real thigh is
a separate structure betwixt it and the shin. Of all birds those
that have crooked talons have the biggest thighs and the strongest
breasts. All birds are furnished with many claws, and all have the
toes separated more or less asunder; that is to say, in the greater
part the toes are clearly distinct from one another, for even the
swimming birds, although they are web-footed, have still their claws
fully articulated and distinctly differentiated from one another.
Birds that fly high in air are in all cases four-toed: that is, the
greater part have three toes in front and one behind in place of a
heel; some few have two in front and two behind, as the wryneck.

This latter bird is somewhat bigger than the chaffinch, and is
mottled in appearance. It is peculiar in the arrangement of its
toes, and resembles the snake in the structure of its tongue; for
the creature can protrude its tongue to the extent of four
finger-breadths, and then draw it back again. Moreover, it can twist
its head backwards while keeping all the rest of its body still,
like the serpent. It has big claws, somewhat resembling those of the
woodpecker. Its note is a shrill chirp.

Birds are furnished with a mouth, but with an exceptional one,
for they have neither lips nor teeth, but a beak. Neither have they
ears nor a nose, but only passages for the sensations connected with
these organs: that for the nostrils in the beak, and that for
hearing in the head. Like all other animals they all have two eyes,
and these are devoid of lashes. The heavy-bodied (or gallinaceous)
birds close the eye by means of the lower lid, and all birds blink
by means of a skin extending over the eye from the inner corner; the
owl and its congeners also close the eye by means of the upper lid.
The same phenomenon is observable in the animals that are protected by
horny scutes, as in the lizard and its congeners; for they all without
exception close the eye with the lower lid, but they do not blink like
birds. Further, birds have neither scutes nor hair, but feathers;
and the feathers are invariably furnished with quills. They have no
tail, but a rump with tail-feathers, short in such as are
long-legged and web-footed, large in others. These latter kinds of
birds fly with their feet tucked up close to the belly; but the
small rumped or short-tailed birds fly with their legs stretched out
at full length. All are furnished with a tongue, but the organ is
variable, being long in some birds and broad in others. Certain
species of birds above all other animals, and next after man,
possess the faculty of uttering articulate sounds; and this faculty is
chiefly developed in broad-tongued birds. No oviparous creature has an
epiglottis over the windpipe, but these animals so manage the
opening and shutting of the windpipe as not to allow any solid
substance to get down into the lung.

Some species of birds are furnished additionally with spurs,
but no bird with crooked talons is found so provided. The birds with
talons are among those that fly well, but those that have spurs are
among the heavy-bodied.

Again, some birds have a crest. As a general rule the crest sticks
up, and is composed of feathers only; but the crest of the barn-door
cock is exceptional in kind, for, whereas it is not just exactly
flesh, at the same time it is not easy to say what else it is.

13

Of water animals the genus of fishes constitutes a single group
apart from the rest, and including many diverse forms.

In the first place, the fish has a head, a back, a belly, in the
neighbourhood of which last are placed the stomach and viscera; and
behind it has a tail of continuous, undivided shape, but not, by the
way, in all cases alike. No fish has a neck, or any limb, or testicles
at all, within or without, or breasts. But, by the way this absence of
breasts may predicated of all non-viviparous animals; and in point
of fact viviparous animals are not in all cases provided with the
organ, excepting such as are directly viviparous without being first
oviparous. Thus the dolphin is directly viviparous, and accordingly we
find it furnished with two breasts, not situated high up, but in the
neighbourhood of the genitals. And this creature is not provided, like
quadrupeds, with visible teats, but has two vents, one on each
flank, from which the milk flows; and its young have to follow after
it to get suckled, and this phenomenon has been actually witnessed.

Fishes, then, as has been observed, have no breasts and no
passage for the genitals visible externally. But they have an
exceptional organ in the gills, whereby, after taking the water in the
mouth, they discharge it again; and in the fins, of which the
greater part have four, and the lanky ones two, as, for instance,
the eel, and these two situated near to the gills. In like manner
the grey mullet-as, for instance, the mullet found in the lake at
Siphae-have only two fins; and the same is the case with the fish
called Ribbon-fish. Some of the lanky fishes have no fins at all, such
as the muraena, nor gills articulated like those of other fish.

And of those fish that are provided with gills, some have
coverings for this organ, whereas all the selachians have the organ
unprotected by a cover. And those fishes that have coverings or
opercula for the gills have in all cases their gills placed
sideways; whereas, among selachians, the broad ones have the gills
down below on the belly, as the torpedo and the ray, while the lanky
ones have the organ placed sideways, as is the case in all the
dog-fish.

The fishing-frog has gills placed sideways, and covered not
with a spiny operculum, as in all but the selachian fishes, but with
one of skin.

Morever, with fishes furnished with gills, the gills in some
cases are simple in others duplicate; and the last gill in the
direction of the body is always simple. And, again, some fishes have
few gills, and others have a great number; but all alike have the same
number on both sides. Those that have the least number have one gill
on either side, and this one duplicate, like the boar-fish; others
have two on either side, one simple and the other duplicate, like
the conger and the scarus; others have four on either side, simple, as
the elops, the synagris, the muraena, and the eel; others have four,
all, with the exception of the hindmost one, in double rows, as the
wrasse, the perch, the sheat-fish, and the carp. The dog-fish have all
their gills double, five on a side; and the sword-fish has eight
double gills. So much for the number of gills as found in fishes.

Again, fishes differ from other animals in more ways than as
regards the gills. For they are not covered with hairs as are
viviparous land animals, nor, as is the case with certain oviparous
quadrupeds, with tessellated scutes, nor, like birds, with feathers;
but for the most part they are covered with scales. Some few are
rough-skinned, while the smooth-skinned are very few indeed. Of the
Selachia some are rough-skinned and some smooth-skinned; and among the
smooth-skinned fishes are included the conger, the eel, and the tunny.

All fishes are saw-toothed excepting the scarus; and the teeth in
all cases are sharp and set in many rows, and in some cases are placed
on the tongue. The tongue is hard and spiny, and so firmly attached
that fishes in many instances seem to be devoid of the organ
altogether. The mouth in some cases is wide-stretched, as it is with
some viviparous quadrupeds. . . .

With regard to organs of sense, all save eyes, fishes possess
none of them, neither the organs nor their passages, neither ears
nor nostrils; but all fishes are furnished with eyes, and the eyes
devoid of lids, though the eyes are not hard; with regard to the
organs connected with the other senses, hearing and smell, they are
devoid alike of the organs themselves and of passages indicative of
them.

Fishes without exception are supplied with blood. Some of them are
oviparous, and some viviparous; scaly fish are invariably oviparous,
but cartilaginous fishes are all viviparous, with the single exception
of the fishing-frog.

14

Of blooded animals there now remains the serpent genus. This genus
is common to both elements, for, while most species comprehended
therein are land animals, a small minority, to wit the aquatic
species, pass their lives in fresh water. There are also sea-serpents,
in shape to a great extent resembling their congeners of the land,
with this exception that the head in their case is somewhat like the
head of the conger; and there are several kinds of sea-serpent, and
the different kinds differ in colour; these animals are not found in
very deep water. Serpents, like fish, are devoid of feet.

There are also sea-scolopendras, resembling in shape their land
congeners, but somewhat less in regard to magnitude. These creatures
are found in the neighbourhood of rocks; as compared with their land
congeners they are redder in colour, are furnished with feet in
greater numbers and with legs of more delicate structure. And the same
remark applies to them as to the sea-serpents, that they are not found
in very deep water.

Of fishes whose habitat is in the vicinity of rocks there is a
tiny one, which some call the Echeneis, or 'ship-holder', and which is
by some people used as a charm to bring luck in affairs of law and
love. The creature is unfit for eating. Some people assert that it has
feet, but this is not the case: it appears, however, to be furnished
with feet from the fact that its fins resemble those organs.

So much, then, for the external parts of blooded animals, as
regards their numbers, their properties, and their relative
diversities.

15

As for the properties of the internal organs, these we must first
discuss in the case of the animals that are supplied with blood. For
the principal genera differ from the rest of animals, in that the
former are supplied with blood and the latter are not; and the
former include man, viviparous and oviparous quadrupeds, birds,
fishes, cetaceans, and all the others that come under no general
designation by reason of their not forming genera, but groups of which
simply the specific name is predicable, as when we say 'the
serpent,' the 'crocodile'.

All viviparous quadrupeds, then, are furnished with an oesophagus
and a windpipe, situated as in man; the same statement is applicable
to oviparous quadrupeds and to birds, only that the latter present
diversities in the shapes of these organs. As a general rule, all
animals that take up air and breathe it in and out are furnished
with a lung, a windpipe, and an oesophagus, with the windpipe and
oesophagus not admitting of diversity in situation but admitting of
diversity in properties, and with the lung admitting of diversity in
both these respects. Further, all blooded animals have a heart and a
diaphragm or midriff; but in small animals the existence of the latter
organ is not so obvious owing to its delicacy and minute size.

In regard to the heart there is an exceptional phenomenon
observable in oxen. In other words, there is one species of ox
where, though not in all cases, a bone is found inside the heart. And,
by the way, the horse's heart also has a bone inside it.

The genera referred to above are not in all cases furnished
with a lung: for instance, the fish is devoid of the organ, as is also
every animal furnished with gills. All blooded animals are furnished
with a liver. As a general rule blooded animals are furnished with a
spleen; but with the great majority of non-viviparous but oviparous
animals the spleen is so small as all but to escape observation; and
this is the case with almost all birds, as with the pigeon, the
kite, the falcon, the owl: in point of fact, the aegocephalus is
devoid of the organ altogether. With oviparous quadrupeds the case
is much the same as with the viviparous; that is to say, they also
have the spleen exceedingly minute, as the tortoise, the freshwater
tortoise, the toad, the lizard, the crocodile, and the frog.