Aristotle · a new plain-English translation from the original language
1| A few have neither a crop nor a wide gullet, but instead a very long one — these are the ones with a long neck, such as the purple coot; and nearly all of these also pass moister excrement than the rest. The quail is peculiar among the others in this respect: it has both a crop and, before the stomach, a gullet that is wide and has breadth to it; and the crop is separated from the gullet in front of the stomach by a considerable distance, relative to its size. Most birds also have a thin intestine, simple, and unwinding into one length. Birds have the blind appendages, as has been said, few in number, and not above as fish do, but below, at the end of the intestine. Not all birds have them, but most do, such as the cock, the partridge, the duck, the night-heron, the lokalos, the horned owl, the goose, the swan, the bustard, the owl. Some of the small birds have them too, but very small ones, such as the sparrow.
2| We have now spoken of the other internal parts — how many there are and of what sort, and what differences they have from one another. It remains to speak of the parts that contribute to generation. These are internal in all females, but in males they show more differences. For some blooded animals have no testicles at all, some have them but internal, and of those that have them internal, some have them near the loin, around the region of the kidneys, others near the belly, and others external. And as for the genital organ in these, in some it is attached to the belly, in others it hangs free just as the testicles do; and among those attached to the belly, it is attached differently in animals that urinate forward and those that urinate backward. Now none of the fish have testicles, nor does any other creature that has gills, nor the whole class of snakes, nor, generally, any footless animal that does not bear its young alive within itself. Birds have testicles, and have them internal, near the loin. And among the four-footed animals that are egg-laying, the arrangement is the same, such as the lizard, the tortoise, and the crocodile, and among the live-bearing animals, the hedgehog.
3| Among those that have the testicles internal, some have them near the belly, such as, among footless animals, the dolphin, and among four-footed live-bearing animals, the elephant; the rest have them visible. What difference there is in the way they are attached to the belly and to the adjoining region has been stated earlier: in some they are continuous from behind and not detached, as in the hog family, in others they are detached, as in humans. Now fish, as has been said before, have no testicles, nor do snakes; but they have two ducts, attached from the diaphragm on either side of the spine, joining into a single duct above the outlet for the residue — by 'above' we mean toward the spine. These become full of milt around the season of mating, and when pressed the semen comes out white. The difference these creatures have from one another must be studied from dissections, and will be stated later, more precisely, in the accounts devoted to each of them individually. All egg-laying animals, whether two-footed or four-footed, have testicles near the loin, below the diaphragm, some whiter, some more yellowish, and entirely enclosed in thin little veins.
4| And from each one a duct stretches, joining into one, just as in fish, above the outlet for the residue. This is the genital organ, which in small birds is not conspicuous, but in larger ones, such as the goose and birds of that size, becomes more evident when mating has recently occurred. The ducts, in both fish and these birds, are attached near the loin below the belly and the intestines, between the great vein, from which ducts stretch to each of the testicles. Just as in fish the milt is visible present around the mating season and the ducts are very clear, but once the season has passed the ducts too sometimes become inconspicuous, so it is also with the testicles of birds: before mating, some have them small, others altogether inconspicuous, but when they are mating, they have them very large. This happens most conspicuously in ring-doves and partridges, so that some people think these birds have no testicles at all in winter. Among those that have the testicles in front, some have them internal, near the belly, as the dolphin does, others have them external, in plain view, near the end of the belly.
5| In these the rest is arranged in the same way, but they differ in that some have the testicles by themselves, while others — those that have them external — have them in what is called the scrotum. The testicles themselves, in all land-dwelling, live-bearing animals, are arranged in this way. Veinous ducts stretch from the aorta as far as the head of each testicle, and two others from the kidneys; these latter are full of blood, while the ones from the aorta are bloodless. From the head, at the testicle itself, there is a duct denser than that one and more sinew-like, which bends back again in each testicle toward the head of the testicle; and from the head each of the two in turn joins together at the same point, forward toward the genital organ. The ducts that bend back and lie against the testicles are enclosed in the same membrane, so that they seem to be a single duct unless one splits the membrane apart. Now the duct that lies against the testicle still has a bloody fluid in it, though less so than the ones above coming from the aorta; but in the ducts that bend back into the shaft within the genital organ, the fluid is white. A duct also runs from the bladder, and joins in above, into the shaft.
6| Around this there is, as it were, a sheath — what is called the penis. Let what has been said be studied by reference to the following diagram. The origin of the ducts from the artery is marked A; the heads of the testes and the ducts leading down to them are marked K; those from these that lie against the testis are marked ΩΩ; those that bend back, in which the white fluid is, are marked ΒΒ; the penis is Δ, the bladder E, and the testes are marked ΨΨ. When the testes themselves are cut off or removed, the ducts are drawn upward. Some destroy them by friction while the animals are still young, others by cutting them out even later; and it has actually happened that a bull, once castrated, mounted immediately after and covered a cow and sired offspring. This, then, is how matters stand regarding the testes in animals. The uteri of animals that have uteri are neither alike in kind nor similar in all cases, but differ both among the live-bearing animals themselves and among the egg-laying ones. All animals that have the uterus near the genitals have it cloven in two, one part on the right side and the other on the left;
7| the point of origin is single and there is one mouth, like a stalk that is very fleshy and, in most and the largest of them, cartilaginous as well. Some of these parts are called uterus and delphys (from which people are also called adelphoi, 'brothers'), while the stalk and the mouth of the uterus is called metra. Now in all animals that are live-bearing and two-footed or four-footed, the uterus lies below the diaphragm — for example in man, dog, pig, horse, and ox; and this holds alike for all the horned animals too. At their upper ends, the uteri of most of them have a coiling in what are called the 'little horns.' Among the egg-laying animals, they are not all alike as seen externally: the uteri of birds lie near the diaphragm, but those of fish lie below, as in the live-bearing two-footed and four-footed animals, except that they are thin, membranous, and long, so that in very small fish each seems to be a single egg — as though these fish, in the cases where the egg is said to be crumbly, had two eggs; for it is in fact not one but many, which is why it disperses into many. The uterus of birds has, in its lower part, a stalk that is fleshy and firm, but the part near the diaphragm is membranous and altogether thin, so that the eggs would seem to lie outside the uterus.
8| In the larger birds, then, the membrane is more evident, and when blown through the stalk it rises and forms a pouch; in the small ones all this is less clear. The uterus is the same in character also in four-footed but egg-laying animals, such as the tortoise, the lizard, frogs, and other such creatures; for the stalk below is single and rather fleshy, while the division and the eggs lie above, near the diaphragm. As for the footless creatures that appear to bear live young but in fact lay eggs within themselves — such as the dogfish and the rest of the so-called selachians (an animal is called a selachian if it is footless, has gills, and is live-bearing) — in these the uterus is cloven in two and likewise extends toward the diaphragm, just as in birds. Further, beginning below, it runs through the middle of the two divisions up to the diaphragm, and the eggs form there, and also above, at the start of the diaphragm; then, once they have advanced into the open space, living creatures are produced from the eggs. The differences among these fish themselves, and between them and the other fish, in respect of the uteri, could be studied more precisely in their shapes from dissections.
9| The class of snakes, too, has differences both from these and among themselves. For the other kinds of snakes lay eggs, but the viper alone bears live young, having first laid eggs within itself; hence its uterine arrangement is much like that of the selachians. The uterus of snakes is long, like the body, and runs, beginning below, as a single continuous duct on either side of the spine, each side being like a separate duct, up to the diaphragm, in which the eggs form in a row, and it gives birth not one at a time but in succession. As for the position of the uterus: all animals that bear live young, both within themselves and visibly, have it above the belly, while all that lay eggs have it below, near the loins. Those that appear to bear live young but lay eggs within themselves have it in both positions: the part below, near the loins, is where the eggs are, while the part near the outlet lies above the intestines. There is also this further difference among uteri: horned animals, and those that are not double-toothed, have cotyledons in the uterus when it contains the embryo, and so do some of the double-toothed animals as well, such as the hare, the mouse, and the bat;
10| but the other double-toothed, live-bearing, footed animals all have a smooth uterus, and the attachment of the embryos is from the uterus itself, not from a cotyledon. This, then, is how matters stand with the non-uniform parts in animals, both the external and the internal. Among the uniform parts, the most common to all blooded animals is blood, together with the part in which it naturally forms (this is called a vein); next comes what is analogous to these in the bloodless animals, namely serum and fibers; and what is most truly the body of animals, flesh, together with the part analogous to it in each kind; further, bone and what is analogous to it, such as spine and cartilage; further, skin, membrane, sinew, hair, nails, and the things acknowledged to belong with these; and besides these, fat, suet, and the residues — these being dung, phlegm, and yellow and black bile. Since the nature of blood and of the veins seems to be a starting point, we must speak of these first, especially since some of those who have spoken before did not speak well of them. The cause of their ignorance is the difficulty of observing these parts. For in dead animals the nature of the principal veins is unclear, because these especially collapse as soon as the blood leaves them (for from these it pours out all at once as from a vessel; for nothing has blood in itself, except a little in the heart, but all of it is in the veins), while in living animals it is impossible to observe how they are arranged;
11| for their nature lies within. And so those who studied the greatest starting points in dead and dissected animals did not in fact observe them, while others, working from what appeared externally at the time in extremely emaciated men, distinguished the origins of the veins — Syennesis the Cyprian physician did so in this way. The thick veins are formed as follows: from the navel, along the loins, through the back, past the lung, under the breasts — one running from the right to the left, the other from the left to the right; the one from the left passes through the liver to the kidney and to the testis, the one from the right passes to the spleen and kidney and testis, and from there to the genital organ. Diogenes of Apollonia says the following. The veins in man are arranged thus. There are two largest ones; these stretch through the belly alongside the spine, one to the right, one to the left, each into the leg on its own side, and upward into the head, alongside the collarbones, through the throat. From these, veins extend through the whole body — from the right one to the right parts, from the left one to the left parts — the two largest into the heart, around the spine itself, and others a little higher up, through the chest, under the armpit, into each arm on its own side;
12| and one is called the splenic vein, the other the hepatic vein. The tip of each of these splits, one toward the big toe, the other toward the instep. From these, thin and much-branched vessels extend to the rest of the hand and the fingers. Other, thinner vessels extend from the first veins, one from the right to the liver, one from the left to the spleen and the kidneys. Those extending into the legs split at the point of attachment, and extend through the whole thigh. The largest of them runs behind the thigh, and shows up thick; another runs on the inside of the thigh, a little less thick than that one. Then they extend past the knee into the shin and the foot, just as they do into the hands; and they reach down to the instep of the foot, and from there extend on to the toes. Many thin veins also branch off from them toward the belly and the flank. Those extending to the head are visible, large, in the neck, running through the throat-vessels; from each of them, at the point where it ends, many branch off into the head, those from the right going to the left, those from the left going to the right —
13| both ending near the ear. There is another vein in the neck, alongside the large one on each side, a little smaller than it, into which most of the veins from the head converge. These extend inward through the throat-vessels, and from each of them branches extend under the shoulder blade and into the arms. Alongside the splenic and hepatic veins other, slightly smaller ones are visible, which they open when something is troubling the patient under the skin; but if the trouble is around the belly, they open the hepatic and splenic veins. Others also extend from these under the breasts. There are others, thin ones, extending from each side through the spinal marrow to the testicles. Others extend under the skin and through the flesh to the kidneys, and end at the testicles in men, and at the womb in women. The first veins, from the belly, are wider, then they become thinner, until they cross over from the right to the left and from the left to the right — these are called the seminal veins. The thickest blood forms under the flesh;
14| but as it passes beyond into these regions it becomes thin, hot, and frothy. This, then, is what Syennesis and Diogenes have said; Polybus speaks as follows. The veins fall into four pairs. One runs from the back of the head, through the neck, on the outside along the spine on either side, down to the hips and into the legs, then through the shins to the outside of the ankles and into the feet; and this is why they perform bloodlettings for pains around the back and the hip from the backs of the knees and the outer ankles. Other veins run from the head, past the ears, through the neck — these are called the jugulars — each on the inside along the spine, past the loins to the testicles and to the thighs, and through the inner part of the backs of the knees and through the shins to the inner ankles and the feet; and this is why they perform bloodlettings for pains around the loins and the testicles from the backs of the knees and the ankles. The third pair runs from the temples, through the neck, under the shoulder blades, and reaches the lung: those from the right go to the left, under the breast and to the spleen and the kidney, while those from the left go to the right, from the lung, under the breast and the liver and to the kidney —
15| both ending at the testicle. The fourth pair runs from the front of the head and the eyes, under the neck and the collarbones; from there they extend through the upper arms, from above, down to the bends of the elbow, then through the forearms to the wrists and their bends, and through the lower part of the upper arms into the armpits, and along the ribs from above, until one reaches the spleen and the other the liver; then, passing over the belly, both end at the genitals. What has been said by the others is, then, roughly this. But there are also among the natural philosophers some who have not worked out such precision about the veins, yet all of them alike make the head and the brain their starting point — speaking incorrectly. Since the observation is difficult, as has been said, it can be learned adequately only in animals that have been strangled and first emaciated, if anyone takes the trouble over such things. The nature of the veins is as follows. There are two vessels inside the chest, along the spine: the larger of them lies in front, the smaller behind it; and the larger lies more toward the right, the smaller toward the left — this is the one some call the aorta, from having observed its sinewy part even in dead animals.
16| These have their starting points from the heart. For through the other internal organs, wherever they happen to run, they pass straight through, remaining intact and being veins throughout; but the heart is, as it were, a part of them — more so a part of the front and larger one — because these vessels lie one above and one below, and the heart lies between them. All hearts have cavities in them, but in very small animals only the largest of these is barely visible; in animals of middling size there is a second one as well; and in the largest animals there are all three. With the point of the heart turned forward, as has been said before, the largest cavity is on the right and at the very top; the smallest is on the left; and the one of middling size lies between the two, in the middle. Both of the smaller ones are far smaller than the largest. All three, however, are perforated toward the lung, though the passages are undetectable because of their smallness, except in the case of one. The great vessel, then, is attached to the largest cavity, the upper one, on the right; then again a vessel extends through the middle cavity, as though that cavity were a part of the vessel in which the blood collects.
17| The aorta runs from the middle cavity — except not in the same way, but communicating through a much narrower channel. And the vessel passes through the heart, while it is from the heart that it extends into the aorta. The great vessel is membranous and skin-like, while the aorta is narrower than it but very sinewy; and as it stretches on, far toward the head and toward the lower parts, it becomes narrow and entirely sinewy. First a part of the great vessel extends upward from the heart toward the lung and the junction with the aorta, remaining an undivided and large vessel. From it two parts split off, one toward the lung, the other toward the spine and the last vertebra of the neck. The vessel extending to the lung, since the lung itself is in two parts, first splits into two, then runs along each channel and each opening, larger along the larger ones, smaller along the smaller, so that there is no part to be found in which there is not both an opening and a small vein; for the last of these are undetectable in size because of their smallness, but the whole lung shows up full of blood.
18| Above, the passages from the vessel lie over those of the channels running from the windpipe. The vessel extending to the vertebra of the neck runs again along the spine — the very one Homer too spoke of in his verses, when he wrote: "and he cut clean through the whole vessel, which running up along the back reaches all the way to the neck."
19| From this vein, small vessels stretch along each rib and to each vertebra, and at the vertebra above the kidneys it splits in two. These, then, are the parts that have split off from the great vein in this way. Above these, again, from the vein extending from the heart, the whole splits into two regions. Some of them carry to the sides and the collarbones, and then, through the armpits, stretch — in humans to the arms, in quadrupeds to the front legs, in birds to the wings, in fish to the upper fins. The starting points of these veins, where they first split, are called the jugulars; and where they split off toward the neck from the great vein, they run alongside the windpipe of the lung. When these are pressed on from outside, people sometimes collapse without choking, losing sensation, their eyelids closed. Stretching in this way, and taking the windpipe between them, they extend as far as the ears, where the jaws of the head meet. Again from there they split into four veins, one of which bends back and descends through the neck and the shoulder, and joins the earlier branch of the vein at the bend of the arm, while the other part ends in the hand and the fingers; another, from each of the regions around the ears, stretches to the brain, and splits into many fine small vessels into the so-called membrane around the brain. The brain itself is bloodless in every animal, and no vessel, small or large, ends in it. Of the remaining veins split off from this vein, some encircle the head in a ring, while others end in the sense organs and the teeth as extremely fine small vessels.
20| In the same way the parts of the lesser vein too, called the aorta, have split, running alongside those of the great vein — except that its channels are smaller, and its small vessels are much smaller than those of the great vein. The veins above the heart, then, are in this condition; but the part of the great vein below the heart stretches suspended through the diaphragm, and is held together, both toward the aorta and toward the spine, by membranous, slack channels. From it one vein stretches through the liver, short but broad, from which many fine vessels stretch into the liver and disappear. From the vein through the liver there are two branches: one ends in the diaphragm and the so-called midriff; the other, doubling back through the armpit into the right arm, joins the other veins at the inner bend. That is why, when physicians bleed this vein, patients are relieved of certain pains around the liver. From its left side a vein, small but thick, stretches to the spleen, and the small vessels from it disappear into it.
21| Another part, split off from the left side of the great vein in the same way, ascends to the left arm; except that the former is the one through the liver, while this is different from the one stretching to the spleen. Further, other veins split off from the great vein: one to the omentum, another to the so-called pancreas. From this, many veins stretch through the mesentery. All these end in one great vein, stretched out alongside the whole intestine and the stomach as far as the gullet. And around these parts many veins split off from them. Now as far as the kidneys each — both the aorta and the great vein — extends as a single vessel; there they attach more closely to the spine, and each splits into two like the letter lambda, and the great vein comes to lie more to the rear than the aorta. The aorta attaches most closely to the spine around the heart; the attachment is by small, sinewy vessels. The aorta, as it leads away from the heart, is quite hollow, but as it proceeds it becomes narrower and more sinewy. Veins also stretch from the aorta to the mesentery, like those from the great vein, except that they fall far short of them in size —
22| for they are narrow and fibrous; they end in fine, hollow, fibrous small vessels. Into the liver and the spleen no vein stretches from the aorta. The branches of each vein stretch to each hip, and both attach to the bone. Veins also carry to the kidneys, from both the great vein and the aorta; but they are spent not into the cavity but into the body of the kidneys. From the aorta, two other channels lead to the bladder, strong and continuous, and others lead from the cavity of the kidneys, having nothing in common with the great vein. From the middle of each kidney a hollow, sinewy vein hangs, stretching alongside the spine itself through the veins; then each of them first disappears into each hip, and afterward they become visible again, stretched out toward the hip. Their ends attach, in males, to the bladder and the genitals; in females, to the womb. From the great vein no vein stretches to the womb, but from the aorta many, closely packed.
23| From the aorta and the great vein, among those that split off, other veins also stretch: some, large and hollow, go first to the groin, then through the legs end in the feet and the toes; and again others, through the groin and the thighs, cross over — one from the left to the right, the other from the right to the left — and join the other veins around the backs of the knees. The condition of the veins, then, and where their starting points hang from, is clear from this. In all blooded animals the region around the starting points and the greatest veins is disposed in this way (for the rest of the multitude of veins is not the same in all, since the parts themselves are not disposed the same way in all, nor do all animals have all of them); yet it is not equally visible in all, but most of all in those richest in blood and largest. For in small animals, and those not rich in blood — whether by nature or by the fatness of the body — it cannot be made out in the same way: in some the channels are jumbled together like certain conduits choked with much silt; others have only a few fibers, and these in place of veins.
24| The great vein is in all animals the most distinguishable, even in the small ones. The sinews of animals are disposed in the following way. Their starting point too is from the heart; for the heart itself has sinews in its largest chamber, and the so-called aorta is a sinewy vein — at least its extreme and outermost parts; for these are without cavity, and have a tension like that of the sinews, where it ends at the bends of the bones. All the same, the nature of the sinews is not continuous from a single starting point, as the veins are. For the veins, as in painted outline-sketches, hold the shape of the whole body in such a way that, in animals thoroughly emaciated, the whole bulk appears full of small vessels (for the same region, when the animals are lean, shows small vessels, but when they are fattened, shows flesh); whereas the sinews are scattered apart around the joints and the bendings of the bones. If their nature were continuous, in emaciated animals the continuity of them all would become visible. The largest parts of the sinews are the one around the part that governs leaping (this is called the hollow of the knee), and another, double sinew, the tendon, and those that assist strength, the spinal ligament and the shoulder sinew.
25| The unnamed sinews are those concerned with the bending of the bones; for all the bones that are joined together where they touch one another are bound by sinews, and around all the bones there is a great quantity of sinews. Except in the head there is none, but the sutures of the bones themselves hold it together. The nature of sinew is that it splits lengthwise, but not crosswise, and it has great tension. A moisture forms around these, mucous, white and glutinous, by which they are nourished and out of which they appear to be generated. Now a vein can be cauterized and survive, but every sinew, once cauterized, is destroyed; and if it is cut through, it does not grow together again. Nor does numbness occur where there is no sinew in the body. Sinews are most numerous around the feet and the hands and the ribs and the shoulder-blades and around the neck and the upper arms. All animals that have blood have sinews; but in those that have no bendings but are footless and handless, they are thin and not evident; that is why in fish they are most evident near the fins.
26| Fibers lie between sinew and vein. Some of them have the moisture of serum, and they extend from the sinews to the veins and from these to the sinews. There is also another kind of fiber, which occurs in blood, though not in the blood of every animal; when these are removed from the blood, the blood does not clot, but if they are not removed, it clots. Now in the blood of most animals they are present, but in that of the deer and the roe and the bubalis and certain others fibers are not present; and that is why their blood does not clot in the same way as that of the others, but the blood of deer clots much like that of hares (the clotting of both is not firm, as in the others, but loose, like that of milk when nothing is put into it to curdle it), while that of the bubalis clots more; for it sets in a manner similar to, or a little less firm than, that of sheep. Concerning vein and sinew and fiber, then, matters stand in this way.
27| The bones of animals are all connected from one origin and continuous with one another, like the veins; and no bone by itself, taken on its own, is anything. The starting point, in all animals that have bones, is the spine. The spine is composed of vertebrae, and extends from the head to the hip-bones. Now all the vertebrae are pierced through, and above, the bone of the head is continuous with the last vertebrae; this is called the skull. The saw-toothed part of this is the suture. This is not the same in all animals alike; for some have a skull of a single bone, like the dog, others a composite one, like man, and in man the female has the suture running in a circle, while the male has three sutures meeting at the top, forming a triangle; indeed a man's head has even been seen without sutures. The head is composed not of four bones but of six; two of these are around the ears, small compared with the rest. From the head the jaws extend as bones. In all other animals the lower jaw moves; the river crocodile alone among animals moves the upper jaw.
28| In the jaws is found the class of teeth, bone that is in one respect unpierced and in another pierced, and alone among bones incapable of being carved. From the spine extend both the pin-bone and the collar-bones and the ribs. The breastbone too rests upon ribs; but these join together, while the others do not join; for no animal has bone around the belly. Further there are the bones in the shoulders, and the so-called shoulder-blades, and those next to the upper arms, and of these, those in the hands. And as many animals as have forelegs have the same arrangement in these too. Below, where the body ends, after the hip-bone comes the hip-socket, and then the bones of the legs themselves, those in the thighs and shins, which are called the shanks, of which the ankles are a part, and of these the so-called spurs in those that have an ankle-bone; and continuous with these are the bones in the feet. Now in as many of the blooded, land-dwelling animals as bear live young, the bones do not differ much, but only proportionally, in hardness and softness and size. Further, some of the bones in the same animal have marrow and some do not.
29| Some animals would seem not to have any marrow at all in their bones, such as the lion, because it has altogether little and thin marrow, and only in a few places; for it has it in the thighs and the upper arms. Of all animals the lion has the most solid bones; they are so hard that when they are struck together fire flashes out of them as out of stones. The dolphin too has bones, but not a spiny backbone. The bones of the other blooded animals in some cases differ slightly, as with birds, while in others they are the same by analogy, as with fish; for of these, the ones that bear live young have a cartilaginous spine, such as the so-called selachians, while the egg-laying ones have a spiny backbone, which stands to them as the spine does to quadrupeds. A peculiarity in fish is that in some of them there are, separate within the flesh, thin small spines. The snake is similarly disposed to fish; for its backbone is spiny. Among the quadrupeds that lay eggs, the larger ones have backbones more bony, the smaller ones more spiny. All animals that have blood have a backbone, either bony or spiny; the other bone-parts belong to some and not to others, but just as the having of the parts themselves varies, so too does the having of the bones within them.
30| For as many animals as have no legs and arms, neither do they have shanks, nor do those that have the same parts but not similar ones; for in these too the difference lies either in degree or in analogy. This, then, is how matters stand concerning the nature of bones in animals; cartilage too is of the same nature as bones, but differs from them in degree. And just as bone does not grow back if cut off, neither does cartilage. In the land-dwelling, live-bearing animals among the blooded, the cartilages are unpierced, and marrow does not form in them as it does in bones; but in the selachians (for these are cartilaginous-spined) there is, in the broad parts along the spine, a cartilaginous substance analogous to bone, in which there is a marrow-like moisture. In the land-dwelling animals that bear live young there are cartilages around the ears and the nostrils and around certain extremities of the bones.
31| Further, there are other classes of parts, having neither the same nature as these nor one far removed from it, such as nails and hooves and claws and horns, and besides these the beak, such as birds have, in those animals in which these parts occur. For these are both bendable and splittable, whereas no bone is bendable or splittable, but only breakable. And the colors of horns and nails and claws and hooves follow the color of the skin and the hair. For in animals with black skin the horns and the claws and the hooves, in those that have hooves, are black, and in white-skinned animals they are white, and in those in between, intermediate. It is the same way with nails too. Teeth are of the nature of bone. That is why among black men, such as Ethiopians and the like, the teeth are white, and so are the bones, but the nails are black, just like the whole skin. Of horns, most are hollow from their point of attachment around the solid bone that grows out from the head inward, but at the tip they have the solid part, and they are simple;
32| Only the horns of deer are solid all the way through and many-branched. And of the other animals that have horns, none sheds its horns, but the deer alone does so, each year, unless it has been castrated; about castrated deer we will speak later. The horns are attached more to the skin than to the bone; that is why in Phrygia and elsewhere there are cattle that move their horns just as they move their ears. Of the animals that have claws (and all that have toes have claws, and all that have feet have toes, except the elephant — for the elephant has toes that are unsplit and only faintly articulated, and has no claws at all), some have straight claws, like man, and some have curved claws, like the lion among land animals and the eagle among birds.
33| Concerning hair and its analogues, and skin, the position is as follows. Hair belongs to those animals that are land-dwelling and viviparous; scaly plates belong to those that are land-dwelling and oviparous; and scales belong only to fish, namely those that lay the crumbly kind of egg. For among the long fish the conger does not have such an egg, nor does the moray, and the eel has no egg at all. The thickness and fineness and size of hairs differ according to the region of the body they are on and according to the kind of skin present; for as a rule, hairs are harder and thicker on thicker skins, and more numerous and longer on skins that are more hollow and moist, provided the region is of a kind to have hair at all. The same holds for the scaly-plated and the scaled animals. Now animals that have soft hair, if they are well fed, get harder hair, while those with hard hair get softer and sparser hair. They also differ according to warmer and colder regions: for example, the hair of men is hard in hot regions and soft in cold ones. And again, straight hairs are soft, while curled hairs are hard.
34| The nature of hair is such that it splits. Hairs differ from one another by more and less of this. Some, changing by degrees toward hardness, no longer resemble hairs at all but spines, as with the hairs of land hedgehogs, which are much like claws; indeed in some animals the class of claws is not at all distinct from that of hairs, because of the hardness of the bones. Of all animals, man has the thinnest skin in proportion to his size. In all skins there is a sticky, mucous substance, less in some, more in others — as in the skin of cattle, from which glue is made; in some places glue is also made from fish. Skin, when cut, is itself without sensation; this is most true of the skin on the head, because the tissue between it and the bone is least fleshy there. Wherever skin exists purely by itself, if it is cut through it does not grow back together — for example the thin skin of the cheek, the foreskin, and the eyelid. In all animals the skin is continuous, and it is interrupted only where the natural passages let moisture out, and at the mouth and the claws. So then, all blooded animals have skin, but not all have hair, but rather as has been said before.
35| Animals change color as they age, and in man they turn white. In the others this happens too, but not very noticeably, except in the horse. Hair also turns white starting from the tip. But most gray hairs grow white from the start. This makes it clear that grayness is not dryness, as some say; for nothing grows dry the moment it is born. In the skin eruption called leuke, all the hairs turn gray; and it has happened before now that people who were ill grew gray hairs, and then, once cured, when these fell out, black ones grew in their place. Hair turns gray more when it is kept covered than when it is exposed to air. In men the temples turn gray first, and the front hair before the back; last of all, the pubic hair. Some hairs are innate, others arise later according to age, in man alone among animals: innate are those on the head and on the eyelids and eyebrows; those that arise later are first the pubic hairs, then those of the armpit, and third those of the chin. For the regions in which hairs grow, whether innate or later-arising, are the same in number. The hairs of the head fall out and thin with age, and these are the first and the most to do so.
36| Of these, only the front ones do; for no one goes bald at the back. Smoothness at the crown is called baldness, and smoothness at the brow is called receding hair; neither of these happens to anyone before he begins to have sexual intercourse. No child goes bald, nor does a woman, nor do castrated men; but if a man is castrated before puberty, the later-arising hairs do not grow at all, while if he is castrated after puberty, these alone fall out, except for the pubic hair. A woman does not grow hair on the chin, except that in a few women a little grows when the menses stop, as for instance among the priestesses in Caria, which is thought to happen as a sign of things to come. In other women too it happens, but less. There are also men and women who from birth lack the later-arising hairs and are at the same time infertile, namely all who are also deprived of pubic hair. Now the other hairs grow in due proportion, more or less, most of all those on the head, then those of the beard, and men with fine hair grow it most of all. In some men, as they grow older, the eyebrows grow so shaggy that they must be trimmed, because they lie over the joining of bones which, as the bones separate with age, let through more moisture. The eyelashes do not grow further, but they fall out once a man begins to have sexual intercourse, and more so in those more given to it;
37| and these are the slowest of all to turn gray. Hairs that are plucked out grow back until a man reaches his prime, but not after. Every hair has a sticky moisture near its root, and as soon as it is plucked out it draws up light objects when touched to them. Animals that are variegated in their hair are already variegated beforehand in their skin, and in the skin of the tongue as well. As for the chin, in some men it happens that both the mustache and the chin are shaggy, while in others these are smooth but the jaws are shaggy; men whose beards come in thin go bald less. Hair grows more in certain illnesses, for instance more in consumption, and in old age, and even in the dead, and it becomes harder instead of soft; the very same things happen also with the claws. Innate hairs fall out more in men given to sexual intercourse; the later-arising hairs grow back faster. Men who have a viscous humor go bald less, and even if bald men acquire it, some of them grow hairy again. A hair that has been cut off does not grow further, but growing up again from below it becomes longer. Fish scales too become harder and thicker with age, and in fish that grow thin and in those that age they become harder. And as four-footed animals grow older, in some the hair, in others the wool, grows deeper but fewer in number;
38| In some animals the hooves become larger as they age, in others the claws, and likewise the beaks of birds. The claws grow larger too, just as the nails do. As for the winged animals, such as birds, none of them changes with age, except the crane; this bird, though gray, has darker feathers as it grows old. But because of the changes that occur with the seasons — for instance when the weather turns colder — some birds that are a single color sometimes turn from black or very black to white, as with the raven, the sparrow, and swallows; but none has been observed to change from the white kinds into black. And with the seasons most birds change their colors, so that one unfamiliar with them would fail to notice. Some animals also change the color of their hair according to changes in the water; for in one place the same animals become white, in another black. And around mating season there are, in many places, waters of this sort, which, when drunk and followed by mating, cause the sheep to bear black lambs — as, for example, in Chalcidice on the Thracian coast, in the district of Assyritis, the river called Cold River did. And in Antandria there are two rivers, of which one makes the sheep white and the other black. The river Scamander, too, is thought to make sheep tawny;
39| and this, they say, is why Homer calls it Xanthus instead of Scamander. Now the other animals have hair neither on the inside, nor on the underside of their extremities, only on the outward-facing parts; but the hare alone has hair inside its jaws as well and under its feet. Further, the whale — the sea creature called mys — has no teeth in its mouth, but has hair like a pig's bristles. Now hair, when cut, grows again from below but not from above; feathers, on the other hand, grow again neither from below nor from above, but simply fall out. The feather of the bee does not grow back once plucked, nor does that of any other creature whose wing is undivided; nor does the sting, when the bee loses it — instead the bee dies. All blooded animals also have membranes. A membrane resembles a dense, thin skin, but it is a different kind of thing, for it can be neither split nor stretched. There is a membrane around each of the bones and around each of the internal organs, both in larger and in smaller animals; but in the smaller ones they are inconspicuous because they are altogether thin and small. The largest membranes are the two around the brain, of which the one next to the bone is stronger and thicker than the one next to the brain itself, and after these, the membrane around the heart. When a bare membrane is cut through it does not grow back together, and bones stripped of their membranes become gangrenous.
40| The omentum, too, is a membrane. All blooded animals have an omentum, but in some it is fatty, in others fat-free. In the viviparous animals and in those with teeth in both jaws it has its origin and attachment from the middle of the stomach, where there is, as it were, a kind of seam in it; and in those without teeth in both jaws likewise from the large stomach. The bladder, too, is membranous, but it is a different kind of membrane. Not all animals have a bladder: all the viviparous ones do, but among the oviparous only the tortoise. When cut through, the bladder too does not grow back together, except right at the origin of the ureter — unless in some altogether rare case, for such a thing has in fact happened before. Now in dead animals it lets through no fluid, but in living ones it also lets through dry concretions, from which stones form in those who suffer from them. In some cases such concretions have even formed in the bladder so as to seem no different from shellfish. Concerning vein and sinew and skin, and concerning fibers and membranes, and further concerning hair and nails and claw and hoof and horns and teeth and beak and cartilage and bones and the parts analogous to these, matters stand in this way.
41| Flesh, and whatever has a nature similar to flesh, lies in all blooded animals between the skin and the bone, or the parts analogous to bones; for as the spine stands to the bone, so the fleshlike substance stands to the flesh in those creatures that have bones and a spine. Flesh can be divided in every direction, unlike sinews and veins, which run lengthwise only. When animals grow lean, flesh disappears and small veins and fibers become visible; but when animals are given richer feeding, fat takes the place of flesh. In those that have much flesh, the veins are smaller, the blood redder, and the internal organs and the stomach small; in those that have large veins, the blood is darker, the internal organs large, the stomach large, but the flesh less. Animals with small stomachs become fat in their flesh.
42| Pimele (soft fat) and stear (hard fat) differ from each other. Stear is brittle throughout and solidifies on cooling, whereas pimele is fluid and does not solidify; and the broths of animals with pimele, such as horse and pig, do not set, while those of animals with stear, such as sheep and goat, do set. They also differ in location: pimele forms between skin and flesh, while stear forms only at the end of the flesh. The omentum too becomes pimele-like in animals with pimele, and stear-like in animals with stear. Animals with teeth in both jaws have pimele, those without teeth in both jaws have stear. Among the internal organs, the liver in some animals becomes fatty like pimele — for instance in cartilaginous fish among the fishes; people make oil from these livers, which is produced by melting them down. The cartilaginous fish themselves are the least fatty of all, both in their flesh and in their stomach, their fat being kept separate. The fat of fish, too, is pimele-like, and does not solidify. All animals are fat either throughout the flesh or in a separate, localized place. Those that do not have their fatness set apart are less fat around the stomach and omentum, as with the eel;
43| for these have little stear around the omentum. Most animals become fat around the belly, and especially those animals that are not active. The brains of animals with pimele are moist and glistening, as with the pig, while those of animals with stear are dry. Among the internal organs, animals become fattest around the kidneys; and the right kidney is always less fatty, and even when animals are extremely fat there is always some deficiency around the middle. Fat forms around the kidneys more in animals with stear, and above all in sheep among animals; for a sheep dies if its kidneys become entirely covered over. This fat around the kidneys comes about through rich feeding, as in Sicily around Leontini; and this is why they drive the sheep out late in the day, so that they take in less food. Common to all animals is the fatty substance around the pupil in the eyes; for all animals that have such a part in their eyes and are not hard-eyed have this part made of stear. Animals with pimele are less fertile, both males and females. All animals grow fatter as they get older rather than when they are younger, and especially once they have reached their full breadth and length and are still growing in depth.
44| Here is how things stand regarding blood. This is the most necessary and most common thing to all blooded animals, and it is not something acquired but belongs to all of them as long as they are not decaying. All blood is in a vessel, in what are called veins, and in nothing else except the heart alone. Blood has no perception when animals are touched anywhere in it, just as the residue in the stomach has none; nor does the brain nor the marrow have perception when touched. Wherever one cuts the flesh, blood appears in a living animal, provided the flesh is not decayed. Blood by nature has a sweet flavor, if it is healthy, and a red color; blood that is worse, whether by nature or by disease, is darker. And the best blood is neither too thick nor too thin, unless it is worse through nature or through disease. In the animal it is always fluid and warm, but on going out it congeals in all animals except the deer and the roe deer and any other that has that same nature; the rest of the blood congeals unless the fibers are removed from it. Of all bloods, that of the bull congeals fastest.
45| Among blooded animals, those that bear live young both within themselves and outside themselves have more blood than those [and] blooded animals that lay eggs. Animals in good condition, whether by nature or through health, have neither too much blood, as animals that have just drunk a fresh draught, nor too little, as animals that are very fat; for fat animals have blood that is pure but scanty, and as they grow fatter they become more bloodless, since fat is bloodless. And fat does not putrefy, while blood, and blooded parts, putrefy fastest, and among these the parts around the bones putrefy fastest of all. The human being has the thinnest and purest blood, while the bull and the ass, among animals that bear live young, have the thickest and darkest. And in the lower parts of the body, or in the upper, the blood becomes thicker and darker. Blood pulses in the veins everywhere at once in all animals alike, and it is the only one of the fluids present throughout the whole body in animals, and it alone is present always, as long as the animal lives. Blood is the first thing to form in animals, in the heart, even before the whole body has been articulated. When it is diminished and released outward in quantity, animals die from losing much of it, and if they lose a very great deal, they die outright.
46| When blood becomes too watery, animals fall sick; for it turns serous, and flows through the body to such a degree that some have actually been observed to sweat blood. And on going out, in some animals it does not congeal completely, or only congeals in a divided and separate way. In sleeping animals, less blood is present in the outer parts, so that when they are pricked it does not flow in the same way. Blood, when concocted, comes to be formed from serum, and fat is formed from blood; and when blood has fallen sick, there results a flux of blood, both the kind in the nostrils and the kind around the seat, and also a viscous discharge. When blood putrefies within the body it becomes pus, and from pus comes callus. The blood of females differs from that of males: in females it is thicker and darker than in males of similar health and age, and near the surface it is scantier in females, but within, females have more blood. Of female animals, woman has the most blood of all, and what are called the menses occur in the greatest quantity of any animal in women. This blood, when it has fallen sick, is called a flux. Women share less than men in other diseases. Few women suffer from viscous discharge or flux of blood or a flow from the nostrils; and if any of these occurs, the menses become worse.
47| Blood also differs according to age, in both quantity and kind: in the very young it is serous and more abundant, in the old it is thick and dark and scanty, and in those in their prime it is in between. And the blood of old people congeals quickly, even while still within the body near the surface; this does not happen in the young. Serum is unconcocted blood, either because it has not yet been concocted or because it has become watery.
48| Now about marrow. This too is one of the fluids present in some blooded animals. All the fluids that are naturally present in the body are contained in vessels, just as blood is in veins and marrow is in bones, while others are contained in membranous structures, and in skins and cavities. In the young, marrow is entirely blood-like, but as animals grow older, it becomes fatty in animals that are fatty, and suet-like in animals that are suety. Not all bones have marrow, but only the hollow ones, and even among these some lack it: the lion's bones for one part lack it, for another part have only a very small amount, which is why some say that lions have no marrow at all, as has been said before. And in the bones of pigs there is less marrow, and in some of their bones none at all. These fluids, then, are almost always innate in animals, but milk and semen come later in life. Of these, the one that is separated off is present in all animals when it is present at all — that is, milk; but semen is not present in all, though in some fish what are called the milt serve this role. Whatever has milk has it in the breasts.
49| Breasts belong to whatever bears live young both within itself and outside itself, such as those that have hair, like the human being and the horse, and the cetaceans, such as the dolphin, the seal, and the whale; for these too have breasts and milk. Whatever bears live young only outside itself, or lays eggs, has neither breasts nor milk, such as fish and birds. All milk has a watery serum, called whey, and a solid part, called curd; the thicker of milks has more curd. The milk of animals that do not have teeth in both jaws congeals (which is why it is made into cheese among the domesticated ones), while the milk of animals with teeth in both jaws does not congeal, just as their fat does not, and it is thin and sweet. The thinnest milk is that of the camel, second is that of the horse, third that of the ass; the thickest is that of cattle. Cold does not make milk congeal, but rather makes it run more; fire congeals it and thickens it. Milk is not produced, in most cases, in any animal before it becomes pregnant. When it is pregnant, milk is produced, but it is useless both at the very first and at the very last. In animals not pregnant, a little milk comes from certain foods, and moreover it has been known to increase in older females already being milked, and in some cases so much that it has sufficed to nurse a child.
50| And the people around Mount Oeta, when any of their she-goats will not submit to mating, take nettle and rub the udders forcibly, because of the pain involved; at first what is milked out is blood-like, then somewhat purulent, and finally milk, no less than in goats that have mated. In males, both among the other animals and in man, milk is not produced in most cases, yet it does occur in some: for instance in Lemnos, milk was milked from the breasts of a he-goat — the male has two, beside the genitals — in such quantity that a small cheese was made from it, and again, when this goat mated, the same thing happened to the kid born from him. Such occurrences people take as omens, since indeed the god, when consulted by the man in Lemnos, foretold that he would come into an increase of wealth. In men, after puberty, a little milk is expressed in some cases; and in those already being milked, it has been known to increase considerably. There is a fatty quality present in milk, which in the congealed part becomes oil-like. Into sheep's milk in Sicily, and wherever there is a greater quantity of it, they mix goat's milk. What congeals most is not only the milk with the most curd, but also the milk that is drier.
51| Some animals have more milk than is needed to rear their young, and it is useful for making cheese and for storing, above all the milk of sheep and goats, and next that of cattle. Mare's milk and ass's milk are mixed in to make Phrygian cheese. There is more cheese-substance in cow's milk than in goat's milk: for herdsmen say that from an amphora of goat's milk they get nineteen curd-cakes of an obol's weight each, and from an amphora of cow's milk thirty. Other animals have only as much milk as suffices for their young, and no abundance, nor any that is useful for cheese-making — for example, all those that have more than two teats: for none of these has either a quantity of milk or milk that curdles into cheese. Milk is curdled by fig-juice and by rennet. Now the fig-juice is worked into wool, and when the wool is afterward washed out into a little milk, this, being mixed in, curdles it. Rennet is itself a kind of milk: it is found in the stomach of animals still suckling.
52| Rennet, then, is milk that has cheese-substance in it, produced when the milk is concocted by the heat of the animal. All ruminants have rennet, and among the double-toothed animals the hare has it. Rennet is better the older it is: such rennet, and that of the hare, is especially good against diarrhea, but the best rennet of all is that of the fawn. The amount of milk drawn from milk-bearing animals, more or less, differs according to the size of their bodies and the differences in their food. For example, in Phasis there are small cattle, each of which is milked in great abundance, while the large Epirot cattle are each milked one amphora, and half again as much from the two teats. The milker stands upright, bending slightly, because he could not reach them sitting down. Apart from the ass, the other four-footed animals in Epirus also grow large, and the largest are the cattle and the dogs. The large animals need more pasture, but the country has abundant good grazing of this kind, and suitable places for every season. The largest are the cattle and the sheep called Pyrrhic, which take this name from King Pyrrhus.
53| Some fodder dries up the milk, such as Median grass, especially in ruminants; other fodder produces much milk, such as cytisus and vetch, except that flowering cytisus is not beneficial (for it causes swelling), and vetch is not beneficial for pregnant animals (for it makes their delivery harder). In general, whatever four-footed animals are able to eat is beneficial for conception as well, and animals that have plenty of food are milked in abundance. Some flatulence-producing foods also produce milk when eaten, such as a large quantity of beans for a ewe, a goat, a cow, or a she-goat; for these make the udder go down. A sign that there will be more milk is when, before giving birth, the udder points downward. Milk continues to be produced for a long time in all animals that have it, if they remain unmated and have suitable food, and most of all in sheep among the four-footed animals: for they are milked for eight months. In general, ruminants are milked for much milk that is useful for cheese-making. Around Torone, cows stop only for a few days before giving birth, and have milk the rest of the time. Among women, the darker milk is better than the white for nursing infants, and dark-skinned women have healthier milk than fair-skinned ones.