Table of Contents 



XI 



xiii 



Preface 



Introduction 



Maps xvi 



LANCELETS, By Henry B. Bigelow and Isabel Perez Farfante i 



Acknowledgments I 



General Discussion I 



Class Leptocardii I 



Order Ampihioxi 3 



Family Branchiostomidae y 



Genus Branchiostoma 8 



Branchiostoma bermudae 1 1 



Branchiostoma caribaeum 1 3 



Branchiostoma -platae 16 



Family Epigonichthyidae 1 8 



Genus Asymmetron 18 



Asymmetron lucayanum 19 



Am.'phioxides Larvae 23 



A m.'phioxides felagicus 25 



Amphioxides valdiviae 27 



CYCLOSTOMES, By Henry B. Bigelow and William C. Schroeder 29 



Acknowledgments 29 



General Discussion 29 



Class Agnatha 30 



Subclass Cyclostomata 30 



Order Myxinoidea 31 



Family Myxinidae 3 1 



Genus Myxine 32 



Myxine glutinosa 34 



Order Petromyzonida 43 



Family Petromyzonidae 43 



Genus Petromyzon 45 



Petromyzon marinus 46 



SHARKS, By Henry B. Bigelow and William C, Schroeder 59 



Acknowledgments ro 



General Discussion go 



Class Chondrichthyes g2 



Subclass Elasmobranchii 63 



Order Selachii 64 



vii 



