XVI 



CONTENTS 



PART IV 



Evolutionary Morphology 



36. The bearing of Physical and Climatic factors on Chordates . 



37. The origin of Chordates, and their radiation as aquatic 



animals ......... 



38. The evolution of the Amphibia : the first land-Chordates 



39. The evolution of the Reptiles ...... 



40. The evolution of the Birds ....... 



41. The evolution of the Mammalia ...... 



42. The evolution of the Primates and Man .... 



415 



422 



431 

 436 

 445 

 452 

 460 



PART V 



43. Conclusions ......... 477 



Classification of the animals and groups of animals mentioned 



in this book ......... 487 



Index 



493 



