This book on ancient fishes unites the work of many specialists coming from different areas of biology. Hagfishes, lungfishes, Chondrosteans, and Holosteans constitute the main subject of study. Fossil records and extant species are compared to establish the conservation or the degeneration of specific characters. However, phylogenetic relationship

Preface. Phylogenetic introduction. The occurrence and function of the NOS/NO system in the heart of the eel and the African lungfish. Evolutionary aspects on the comparative biology of lungfishes: emphasis on South American lungfish, Lepidosiren paradoxa. Developmental metabolism of the Australian lungfish, Neoceratodus forsteri. Aestivation in African lungfishes: Physiology, biochemistry and molecular biology. Anatomy of the heart and circulation in lungfishes. The cardiac outflow tract of primitive fishes.Control of breathing in primitive fishes. The lung-swimbladder issue and the complex hierarchical nature of homology: A simple case of homology - Or not? The gut and associated organs in the African lungfish Protopterus annectens. Morphology, histology and functional structure of the alimentary canal of sturgeon. The structural organization in the olfactory system of the teleosts and garfishes. Hagfish slime and slime glands.