During their conversation they had drawn neat the base of the hills,
which sloped gently, and were not above fifty feet in height.
Maskull now began to see strange specimens of vegetable life. What
looked like a small patch of purple grass, above five feet square,
was moving across the sand in their direction. When it came near
enough he perceived that it was not grass; there were no blades, but
only purple roots. The roots were revolving, for each small plant in
the whole patch, like the spokes of a rimless wheel. They were
alternately plunged in the sand, and withdrawn from it, and by this
means the plant proceeded forward. Some uncanny, semi-intelligent
instinct was keeping all the plants together, moving at one pace, in
one direction, like a flock of migrating birds in flight.

Another remarkable plant was a large, feathery ball, resembling a
dandelion fruit, which they encountered sailing through the air.
Joiwind caught it with an exceedingly graceful movement of her arm,
and showed it to Maskull. It had roots and presumably lived in the
air and fed on the chemical constituents of the atmosphere. But what
was peculiar about it was its colour. It was an entirely new colour--
not a new shade or combination, but a new primary colour, as vivid
as blue, red, or yellow, but quite different. When he inquired, she
told him that it was known as "ulfire." Presently he met with a
second new colour. This she designated "jale." The sense impressions
caused in Maskull by these two additional primary colors can only be
vaguely hinted at by analogy. Just as blue is delicate and
mysterious, yellow clear and unsubtle, and red sanguine and
passionate, so he felt ulfire to be wild and painful, and jale
dreamlike, feverish, and voluptuous.