178 FIRST FORMS OF VEGETATION. 
stituted for the rare and expensive foreign orchils. 
Many of them have been known to the rural in- 
habitants from time immemorial. The parti-col- 
oured and often exceedingly beautiful tartans of 
the Highland clans, used to be dyed with the col- 
ouring matter derived from the common grey foli- 
aceous lichens which so plentifully clothe almost 
every tree and wall ; and many an old woman in 
the remote parts of Scotland, skilled in the medi- 
cinal and dyeing properties of the various plants 
Fic. 16.—LECANORA TARTAREA. 
that grow around her humble home, still prefers 
the dyes she herself prepares, by simply boiling 
in water heather twigs, birch leaves, roots of the 
ruadh or yellow bed-straw, or the various species 
of crotal or lichens, to logwood, madder, indigo, 
copperas, or any other of the imported dyes of the 
shops; and the results she produces, by a skilful 
combination of these simple substances, are really 
astonishing ; many of the stuffs which have under- 
gone her primitive dyeing process, being as bril- 
liant and lasting in colour as those which have 
