CONTENTS. 



PAGE. 



Introduction 73 



Decapoda Macrura 75 



Decapoda Anomura 82 



Arnphipoda 87 



Isopoda 89 



Echinoderms 91 



Polychaeta 91 



Colouration of the Mj'zostomids and its Relation to that of their Hosts 93 



Gasteropoda 95 



Summary , 96 



72 





