But the gray lichen seemed to take it up and diffuse it.

At last the gray lichen ceased to be.

The south-facing sides of these stones sometimes bore lichens, yellow and grey.

All the north-facing surfaces were covered in grey lichens.

Lethargy, like the grey lichen that covered everything, clung to our limbs, bleeding strength with every step.

"Come here, then, and sit down," he said, taking his seat on a fallen log, felled so long ago that it was covered with gray lichen.

The boulder was twenty feet high and covered with gray green lichen, devoid of footholds, too steep to climb.

Their route became a steep scramble between white boulders speckled with green and grey lichen.

Most of the horizontal stones are covered in grey, black and light green lichens and mosses.

The whole of it was covered with gray lichen.