Only 30 years ago the chemistry of bryophytes was virtually unknown. Recent research on the biology of bryophytes and progress in analytical techniques has resulted in a deeper knowledge about the chemical constituents of bryophytes, although our understanding of their biochemical processes, especially biosynthetic pathways, compared to vascular plants, is still rather poor. In the first part of this chapter the present state of the art regarding the chemistry of bryophytes will be presented, the second part deals with some aspects of chemosystematics, and in the third part knowledge of the biochemistry of bryophytes is summarized. A recent thorough and comprehensive review on the topic has been published by Asakawa (1995). A further review, in 1997, on “heterocyclic compounds in bryophytes” was published by the same author. He deals mainly with secondary metabolites and does not mention inorganic compounds. Primary metabolites are partly discussed, e.g., lipids, carbohydrates, and phaeophytins. Biochemistry was not a topic of his review; this field of research was recently surveyed in Chopra and Bhatla (1990) and Rudolph (1990).

In the section ‘Chemistry of bryophytes’, present knowledge about inorganic compounds and primary metabolites, their structural analogues, and other ubiquitous compounds in bryophytes will be discussed, followed by the main classes of secondary products. The examples mentioned here are selected from recent original papers not cited in Asakawa (1995, 1997); they are more or less confined to those compounds typical of bryophytes in general.