104 



NATURAL HISTORY 



Sub -phylum I 



HEKIC«ORT>ATA 

 half - CL ' cViorcC 



Sub • pliylum H 



Urockorbata 



chor*<jC - in- t<xil 



CI) 

 Tunicate. 



CI.) 



sute-pViylvcm, uc 



CEPHALOCKORDOTA 



cViorcC-in- Vj«acC 



^ 



(1^ ri'^^i 



Arophioxus ' 

 Iccnc-elet 



ammals '*\/it*h a -notocVjorcC 



(A) SUPERCLASS AGNATHA 



(c) Superclass tetrapoda 



(ii fossil Ostracoderm 



'Pbsrichthys 



(2 ) Cyclostoma.to. 



^etronwjjon. . lamprey 



CB) SUPERCLASS PI5CE6 





(1) ^ 



A-mphibia 

 frog- 



(3) 



Aves 

 bird 



"ReptiLia 

 turtle 



sub-phylura IS" 



VERTEBRATA 



'->vit/Vi "toccc-Vctoones 



"Mammalia 



