Apparently the vegetable kingdom in Mars, instead of having green
for a dominant colour, is of a vivid blood-red tint.  At any rate, the
seeds which the Martians (intentionally or accidentally) brought with
them gave rise in all cases to red-coloured growths.  Only that known
popularly as the red weed, however, gained any footing in competition
with terrestrial forms.  The red creeper was quite a transitory
growth, and few people have seen it growing.  For a time, however, the
red weed grew with astonishing vigour and luxuriance.  It spread up
the sides of the pit by the third or fourth day of our imprisonment,
and its cactus-like branches formed a carmine fringe to the edges of
our triangular window.  And afterwards I found it broadcast throughout
the country, and especially wherever there was a stream of water.