Each is illustrated with a fine line drawing by Eleanor Catherine and, where possible, by a photograph of the plant in its natural habitat, mostly taken by the author during expeditions to the Americas and China. Details of cultivation are also provided by Holger Perner, a well-known German slipper orchid grower. Introductory chapters cover the history of the genus, its morphology and anatomy, cytology, biology, ecology, conservation, evolution, and classification. One chapter chronicles the decline of the British plant and current attempts to save it. Kew is fortunate in having several species of Cypripedium in its living collections and this has permitted Dr Tony Cox and co-workers to compare a DNA analysis of the genus with taxonomies based on morphological characters.
Extant taxa seem to be characterised by high degrees of morphological and DNA divergence.
This may be due to either long periods of isolation or extinction of intermediate forms. Many papers related to the combination of different data matrices. For example, at 'Advances in Plant Molecular Systematics' in Glasgow, Dr Mark Chase gave an invited paper written with Dr Renee Grayer and others on the combination of molecular and phytochemical data. Also this summer, Dr Dick Brummitt attended a meeting of the committee for the Species Plantarum Project, of which he is convener, at the California Academy of Sciences. The project aims to produce a World Flora giving all basic taxonomic data down to species and infraspecific levels.