SCHEME OF CLASSIFICATION 



xvn 



Sub-Class. 



Order. 



Sub-Order. 



DIPNEUSTI f 

 = DIPNOI \ 



(p. 505) I 



Division. Familj-. 



C Triacanthidae (p. 722). 

 Lerodermi I Triodontidae (p. 723). 



'j Balistidae (p. 723). 

 ' Ostraciontidae (p. 724). 

 [ Tetrodontidae (p. 726). 

 - Diodontidae (p. 726). 

 ( Molidae (p. 726). 

 C Ctenodontidae (p. 505). 

 | Uroncmidae (p. 507). 

 I Ceratodontidae (p. 507). 

 V Lepidosirenidae (p. 511). 



OF UNCERTAIN POSITION 



P.ILAEOSPOXVVLIDAE (p. 521). 



OSTRACODERMI (p. 522) 



AXTIARCHI (p. 532) 



ARTHRODIRA (p. 535) 



Order. 



HETEROSTRACI (p. 524) 



OSTEOSTRACI (p. 527) 



ANASPIDA (p. 531) 



Family. 



f Coelolepidae (p. 524). 

 I Drepanaspidae (p. 525). 

 1 Psammosteidac (p. 526). 

 V. Pteraspidae (p. 527). 

 ( Ateleaspidae (p. 528). 

 -j Cephalaspidae (p. 528). 

 [ Tremataspidae (p. 530). 



Birkeniidae (p. 531). 



Asterolcpidae (p. 534). 



Coccosteidac (p. 536). 





