Huimur are the most common beasts of burden of the Commonwealth and are found everywhere on the raised roads. It is from these creatures that the Wise have bred the vast huimur or ruhuimur which are the core of the legions of the Masters and which are commonly referred to in Vulgate as 'dragons'. Both species are characterised by their four horns and bony crests.
Description given in The Chosen:
"Carnelian peered round the edge of his saddle-chair but could make no sense of what he saw. A huge wedge of bone swaying ponderously from side to side, tapering down to a cruel beak. Horn stumps curved out from the four corners of the wedge behind which, more bone fanned out in a fluted crest.
'Out of the way, barbarian, or by the horns I'll run you down.'
A small man was creasing his belly against the mottled edge of the crest. A tarpaulined mound rose behind him, criss-crossed with thongs. The man grimaced as he shook his hooked goad at Carnelian.
There was an impact to the side of his saddle-chair. Carnelian whisked round just as the reins were snatched from his hand. The cowled figure of one of the Masters leaned back as he pulled Carnelian's aquar out of the way.
'Try and be more careful,' his father cried.
Humiliation stung Carnelian to anger. A smell of malt distracted him from any outburst. He turned to see bronze hide flexing. His chair shook as he watched the monster lumber by. A wagon pole juddered past like a battering ram. Then the edge of a solid wheel of wood rolled into view, its splintered rim turning slowly. It lurched into a rut, causing Carnelian's aquar to flare its eye-plumes. He was shaken around in his chair as the creature recoiled.
Carnelian saw the other Masters nearby, waiting for the wagon to pass. He moved towards them, recognized Jaspar by his gloves and drew close to him. 'Was that a dragon?' he shouted in Vulgate over the noise.
'What?' the Master shouted back. 'No, no, no. Though a huimur, it is of a species far smaller than those used by the legions.'