CONTENTS 



PAGE 



Preface 



V 



Scheme of the Classification adopted in this Book 



HEMICHOEDATA 



CHAPTER I 



Chokdat'a and Vertebrata — Hemichordata — Enteropneusta — Ex- 

 ternal Characters and Habits — Structure — Genera — Develop- 

 ment — Pterobrakchia — C'EPH.iLomscus AND Rhabdopleura — Phoko- 

 nidea — Phoronis and Actinotrocha — Affinities of the Hemi- 

 chordata 



TUNICATA 



CHAPTER II 



Introduction — Outline of History — Structure of a typical Ascidian 



— Embryology and Lifr-htstory . 35 



CHAPTER III 



Classification : Lakvacba — Appendicularians — Structure, etc. — 

 Asoidiaoea— SiMPLK Ascidians — Specific Characters — Compound 

 Ascidians — Gemmation — M erosomata — Holosomata — Pyrosoma- 

 xidae—Thaliacea—Doliolidae—Salpidae— General Conclusions— 

 Phylogeny ■ . . 63 



CEPHALOCHORDATA 



CHAPTER IV 



Introduction — General Characters — Anatomy of Amphioxus — 

 Embryoloqy and Life-history— Classification of Cephalochordata 

 — Species and Distribution . . .112 



vn 



