282 



FISHES, LIVING AA r D FOSSIL 



XIX. THE SUPPOSED DESCENT 



Interrelationships and lines of descent as suggested by a number of 

 noted on each scheme. * Denotes that the diagram is the present writer's 



Howes ('91)* 

 (Oil T'rino Genital System) 



Smith Woodward ('!))* 



(On Palaeontology) 



Nephrorchidic 



(Ela.-mobranchs 



Batrachians 



Amniotes) 



Euthurchidic 



(Ganoids 



Teleosts 



Marsipobranchs 



Dipnoans) 



Ostracoderms 



Haeckel C98)* 



(On Genera 



Anatomy) 



Proselachian 



Cyclostome 



Teleosts 



Selachian 



. ^v. Chimaeroid 



\ Palaedipneusten 



\ \ 



Proganoid \ 



\ 



Dipnoan 



Ganoid and 



\ 



Ganoids 

 Crossopterygians 



'Sharks 



K I a,i I -< h ('98) 



(On Aiial Skeleton) 



Cartilaginous /\ PerichorHnl Cartilaginous 



Chordal Verte- f ( Vertebrae. 



brae 



Teleost Amphibian 



Shark 



W.N.Parker C5*2)* 



(On General Anatomy) 



Ancestral Stem 



of Amphibians 



and Fishes 



Acipeueer' \ Teleost 



Lepidosteus 

 Cope ('85)* 

 (On General Anatomy and Palaeoutology) 



Amphibian 

 Dipnoan 

 Ganoid 



Ichthyotome 



Selachian 



Ganoid - 



Burckhardt ('92) 



(On Central Nervous System) 



Selachian / v Petromyzon 



. Dipnoan 



~^J 



Chimaeroid 



Dipnoan 



\ 



Amphibian 



Elasmobraneh 

 Crossopterygian 

 Teleost' X Chondrostei 



(Nervous Syste 



Cerato'duB Protopterus 



Teleost 



Reptile 



Progauoid 



Acipeuser, 



Amphibia ^^ Bony Gauoids 



Teleosts 



ami End Organs) 



Petroruyzun 



Proselachian 



Shark 



