CONTENTS ix 



CHAPTER XIV 

 Class Gasteropoda — Amphineura and Prosobranchiata . . . 400 



CHAPTER XV 



Class Gasteropoda (^continued) : Opisihobranchiata and Pulmonata 427 



CHAPTER XVI 



Classes Scaphopoda and Pelecypoda 444 



BEACHIOPODA (RECENT) 



CHAPTER XVII 



Introduction — Shell — Body — Digestive System — Body Cavity — 

 Circulatory System — Excretory Organs — Muscles — Nervous 

 System — Reproductive System — Embryology — Habits — Dis- 

 tribution — Classification 463 



BEACHIOPODA (FOSSIL) 



CHAPTER XVIII 



Introduction — Division L Ecardines — External Characters — In- 

 ternal Characters — Division II. Testicardines — External 

 Characters — Internal Characters — Synopsis of Families — 

 Stratigraphical Distribution — Phylogeny and Ontogeny . . 491 



