X CONTENTS. 



PAGE 



CHAPTER XIV. 



MOLLUSCA. 

 General Characters — Lamellibranchiata — Type : Anodonta— 



Gasteropoda— Type : Helix— Cephalopoda— Type : Sepia, 298 



VERTEBRATE ANIMALS (CHORDATA). 



CHAPTER XV. 

 Characters and Affinities of Vertebrates 344 



CHAPTER XVI. 



Hemichordata. 



Balanoglossus — Cephalodiscus, . . 35° 



CHAPTER XVII. 



Tunicata or Urochordata. 



General Characters — Description of Ascidian — Larvacea — 



Ascidiacea — Thaliacea, ..... 357 



CHAPTER XVIII. 



Cephalochordata. 



Amphioxus, .... . 364 



CHAPTER XIX. 

 Structure and Development of Vertebrates. 

 Skin — Muscular System — Skeletal System — Nervous System — 

 Alimentary System — Body Cavity — Vascular System — Re- 

 spiratory System — Excretory System — Reproductive System 

 , — Development, . . . . ■ 37 ■ 



