Originally published in 1913, this book was intended to familiarise students of British Vascular Plants with the system of plant taxonomy devised by Adolf Engler (1844–1930). The major divisions of the vascular plants with their diagnoses are taken, to a large extent, verbatim from the seventh edition of Engler's Syllabus der Pflanzenfamilien (1912). This book will be of value to anyone with an interest in botany, plant taxonomy and the history of science.