The evolutionary origin and early history of the angiosperms (or flowering plants), which are the dominant land plants today, has remained an unsolved problem since the time of Darwin. It has been referred to since those days as an 'abominable mystery', because neither direct ancestor nor an agreed date could be determined. Mr Hughes argues that previous approaches, mostly through botanical theory, have been inadequate and misleading. He suggests that the date is about 110 million years ago (in the Cretaceous period) and there is a good chance of ancestors being found if the correct approach is adopted to the study of other fossil plants of that period. Moreover, the study of plant microfossils in the past twenty years has made feasible a fuller geological study of other fossils. When this book was first published in 1976, several reviewers saw it as a timely book on a controversial subject.