This book is the first county lichen flora for any part of Britain. The first half of the book looks at lichens, what they are, their reproduction, lifestyle, habitats etc. and explains how to identify them. It is written in as user-friendly way as is possible for what is a complex subject.
The second half of the book is a species list (with comments which habitats they are found in and abundance) for Shetland. Some 450 species are known to occur here.