Set a horn on a serpent's head and it stops being a snake and becomes a dragon. In a compilation of Chinese myth published in 1922, the Chinese dragon is assembled from borrowed parts — nine 'resemblances', each limb quoted from another beast — and the first of them is the crown: "its horns resemble those of" "a deer". The horn is no idle ornament. Some dragons, the same witness reports, have no ears at all, "the organ of hearing being said to be in the horns", so that the creature "hears through" "its horns". The horn is thus both rank and sense-organ: it marks the beast as sovereign among "the three hundred and sixty scaly reptiles" and it is the very ear by which it listens to the world. Growing a horn is, for this animal, a promotion. The witness lists "azure, scaly, horned" and hornless kinds that ripen one into another, noting that "a horned dragon" in a thousand years "changes to a flying dragon" — the horn is a stage of life, a thing acquired on the way up.

The same chapter's crowning image, in a later part of the shelf, watches the horn actually arrive. A patient white horse, its long labour done, is led to the banks of the "Pool of Dragon-transformation", plunges in, and rises "a four-footed dragon", the served text says, "with horns, scales", claws and wings complete — and from that moment becomes chief of the celestial dragon tribe. The horn does not decorate the transformation; it is one of the signs that the transformation has taken. Thompson filed the horns of the dragon as a trait in their own right, citing a study of the dragon and further Chinese authorities our shelf keeps but has not yet opened.

If a beast hears through the very horns that crown it, is listening, for a dragon, the same act as ruling?