Unique, individual

Like snowflakes no two are the same. The amazing thing is that the lichen is growing in my garden although I live in a large city. Lichens absorb water and minerals from rainwater and directly from the atmosphere, over their entire surface area. This makes them extremely sensitive to atmospheric pollution. As a result, there are usually very few lichens around industrial centres and towns. Different lichen species vary in their tolerance to pollution and therefore make very good biological indicators of levels of atmospheric pollution.

Information from: http://www.countrysideinfo.co.uk/fungi/lichens.htm

I found this really beautiful plate on the internet

Source: Kunstformen der Natur (1904), plate 83: Lichenes 

Author: Ernst Haeckel (1834–1919)

German naturalist, philosopher and artist

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