CONTENTS 



Introduction P a S e 3°3 



Interpretation of Busk's work 303 



Acknowledgements 304 



List of stations, and of the species collected at each 305 



List of species discussed 318 



Systematic descriptions 319 



Geographical distribution of species 477 



The relation between hydrological conditions and the distribution of the 



species 491 



Geographical distribution of genera 492 



Seasonal distribution of ancestrulae 497 



Note on the vermiform bodies found in some Polyzoa 499 



Addendum 501 



References 501 



Index 506 



Plates V-XIII following page 510 



