Pengelly, a lecturer in herbal therapies at the U. of Newcastle, New South Wales, originally wrote the reference as an undergraduate text, but it's also useful for health practitioners, lecturers, researchers, and producers of herbal remedies. A non-chemist writing for other non-chemists, he describes the chemical structures of plants as a means of explaining what makes each herb work. The revised edition includes an expanded introduction to plant molecular structures and adds chapters on fixed oils and triterpenoids. Distributed by Oxford U. Press. Annotation ©2004 Book News, Inc., Portland, OR (booknews.com)