The major purpose ofthis third volume in The Flavonoidsseries is to provide a detailed review of progress in the field during the five years, 1981-1985 inclusive. It thus continues the comprehensive coverage of the literature on these fascinating and important plant pigments which began in 1975 with the publication of The Flavonoids and which was followed in 1982 with The Flavonoids: Advances in Research. As with the two previous vo1umes, this one is entire1y se1f-contained and where necessary tabu1ar data and references from earlier vo1umes are included and expanded here. A unique feature is the complete listing in the Appendix ofall known flavonoids, which now number over 4000 structures; in this list, structures newly reported during the period 1981-1985 are so indicated. The first ten chaptersofthis book provide a critical review ofthe new substancesthat have been discovered among each of the main classes of flavonoid during the period under review. Again, the numberofnew isoflavonoids reported outweighs that ofother classesand ahundred pagesare needed to describe all the nove1 findings.
Neoflavonoids, which were omitted in the first supplement, have been included again and a special chapter on miscellaneous flavonoids has been introduced to cope with those structures (e.g. homoisoflavonoids) which do not fit in easily anywhere else. Although there have been advances in flavonoid methodology, these have not been asspectacular as in earlier years. Hence, literature reports on new chromatographic and spectral procedures are included here in the individual chapters under the different flavonoid classes.