TABLE OF CONTENTS 



CHAPTER I. PRINCIPLES OF VERTEBRATE MORPHOLOGY 



The fundamental architectural plan of vertebrates 1-8 



A physiological interpretation of the fundamental structural plan of 



vertebrates 8-12 



Generalized, specialized, senescent, and retarded (paedogenetic) 



types of vertebrates 12-22 



Vertebrate phylogeny 22-33 



CHAPTER II. THE PHYLUM CHORDATA ' 



Cephalochordata 33^8 



Urochordata 48-60 



Hemichordata. 60-68 



Craniata (Vertebrates) 68-70 



CHAPTER III. THE ORIGIN AND EVOLUTION OF THE VERTEBRATES 



The Amphioxus Theory 72-75 



The Annelid Theory 77-79 



The Arthropod Theory .79-82 



Minor Theories 82-86 



CHAPTER IV. CYCLOSTOMATA 



Myxinoidea 89-91 



Petromyzontia 91-96 



CHAPTER V. PISCES (FISHES) 



Introduction to Pisces 97-112 



Elasmobranchii 112-127 



Teleostomi m . *, 127-153 



Dipneusti 153-159 



Generalized and specialized types of fishes and the axial gradient 



theory of structural relations 159-163 



Eggs, reproduction, and breeding habits of fishes 163-168 



Appendix to fishes (Ostrachodermi, etc.) . 168-172 



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