History of All Cloven-Hoofed Quadrupeds

...sium have been given in various ways: but those which are rightly understood as horns belong only to the quadruped genus. For I reckon Actaeon and Cippus in Latin history to be fables. Nor elsewhere has a greater playfulness of nature sported with the weapons of animals. She scattered these in branches, as in stags; to others she granted simple ones, as in the same genus to the spikers, so called by reason of the thing itself;
Platycerotae

of others she shaped them into palms, and sent forth fingers from them, whence they call them platycerotae. She gave branched ones to roe deer, but small, and did not make them deciduous. Twisted into a coil for the ram kind, as if she gave them boxing-gloves, hostile to bulls. In this genus indeed, she gave them also to females; in many [others], only to males. In chamois they are hooked toward the back; in fallow deer, toward the front. But erect,
Strepticeros.

and twisted in a circuit of wrinkles, and sharpened to a light point, so that you might call them lyres, for the Strepticeros, which Africa calls the Addax. The same are movable, like ears, as with the herds of Phrygia; those of the Troglodytes are directed toward the ground, for which reason they graze with a tilted neck. To others they are singular, and these in the middle of the head or on the nostrils, as we have said. Indeed, because for some they are robust for charging, for others for striking; for some hooked, for others for tossing in many ways, bent backward, turned, connected. All tapering to a point. In a certain genus, they are used instead of hands for scratching the body. For snails, for feeling the way. Thus far Pliny, no mention having been made of the color of horns; and there is no small ambiguity regarding the variety of colors of which we spoke. For Aristotle writes that nails, hairs, horns, and other things of that kind sprout from the skin itself,
2. de generat. cap. 4.

and are stained with its color: which is confirmed by the same Philosopher in two other places; and giving the reason for this kind of staining,
3. Hist. 9. & lib. de colorib.

he says it is because in all [animals] nourishment is filtered through the skin to the outer circuit. But the reason for doubting is this: the horns of oxen have a blackish point, although they are almost entirely white. If therefore
Observation on the color of horns.

the skin stained the horns with its own color, they would not receive, it appears, this variety of colors. And although in the same book Aristotle says that blackness comes from age, and the extremities of horns, since they erupt first, are older than the other parts of them, the reason nevertheless is not sufficient: for the points of all horns ought to be black; moreover, those of black animals ought to be black, and those of red [animals] red. Finally, since the skin is of one color, the horns ought to be of one color; yet we read of some being multicolored, provided it is true what Aelian recorded concerning the unicorn ass. Regarding solidity, it must also be noted that all horns, though empty inside, were made solid by nature at both ends: in the base indeed, that they might be more firmly fixed to the forehead; but at the tip, that they might be stronger for striking. And Aristotle noted
Observation on the solidity of horns.

that the solid part which fills the inner cavity is by no means a part of the horns, but rather a certain exuberance of the skull. Two-horned animals armed with solid horns are very few, lest they be weighed down by too much weight. For just as bones are hollow, except for certain very small ones which nature has constructed especially in the hands
3. de par. 1.

and feet to strengthen the offshoots of the nerves, or if you prefer, tendons. Aristotle attributes solidity of horns to the stag alone: To the stag (he says) alone of the horned animals are the horns entirely solid; for the others they are hollow to some extent. Yet the horns of the roe deer are also solid, though much smaller; so are those of the elk, and perhaps also of others. Observing which, Albertus says:
3. de par. 2. 2. Hist. 1.

Furthermore (he says), the horns of many animals are empty near the head and solid at the end, except in the stag, and those having a nature similar to the stag, such as the roe deer, and the hircocervus, and such like, which are hard at both ends and are of much branching.

Finally, it must be noted that the same Philosopher calls horns the parts nearest to the bones. For the material is not simply
3. de animal mollitiẽ, tract. 2. c. 1.

bony, but also nervous, because they are thus stronger, which Galen also asserts in these words:

For all the protruding and naked parts of animals He created from such a substance as could neither be easily crushed because of softness, nor broken because of dryness: such a part is the hoof, as much the solid as the cloven; such is the spur; such is the horn.

Someone will say, if the material of the horn is nervous, it will also have the power of feeling, of
Material of horns. 1. de usu par. 12.

which horns are entirely devoid; likewise, if the material is earthy, how will it happen that they soften, which ancient authors report horns do, and use also confirms. The first doubt is removed if we say the material is not simply nervous, but drossy, which on account of its intemperance and thickness does not admit sensation. We have the solution to the other question in Aristotle in these words:

But those [parts] which arise as quite earthy, having obtained little moisture and heat, when these are cooled, the moisture evaporating with the heat, they take on a hard and earthy form, such as nails, hoofs, horns, and beaks; wherefore they are softened by fire.

For according to him, all things are soften-able which do not consist of congealed water, but which rather belong to earth, and neither is their entire moisture dried out, nor unequally; but they are tractable and not moistenable, or ductile and not aqueous, and are soften-able by the work and
2. de gener. cap. 4.

heat of fire, such as iron, horn, and wood. Where again it must be observed that Aristotle understood by the whole fluid a thick fluid, perceptible to the senses, but not that the whole fluid entirely vanishes and is dissipated through vapors; and therefore since such things congeal with cold,
4. Meteor. 9.

they thereafter become softer with heat: for by heat that internal moisture is melted, which, being melted, produces softness where hardness had previously existed while it lay hidden within; just as leather prepared by art becomes flexible and tractable if it is brought near fire, which before was felt to be rigid. Although therefore such things are earthy, they nevertheless have retained for themselves a little moisture, and that indeed glutinous, which
Parts proper to horned animals or ruminants.

is recalled to the senses by fire. Now, horned animals have certain other parts of the body proper [to them] and common to no others, such as the talus and suet; some common indeed with others, but different in position, such as the uterus, breasts, and spleen. Concerning the talus we read these things in Aristotle. The talus...