TABLE XXI. 



Pedigree of Vertebrates. (Cf. Plate XV.) 



Primitive fishes Selachii 

 3. Fishes Pisces 



Amphirhina 



Dipneusta 



Lampreys Hags 



Petromyzontes Myxinoides 



2. Round-mouths 



Cylostoma 



I 



,SmijIt=n0striIlclJ Monorhina 

 Craniota 



Chordonia 



Worms 

 Verm** 



