VI 



TABLE OF CONTENTS. 



PAGE 



Articulated Animals . . 405 



Insects 405 



Myriapoda . ., . . .454 



Arachnida 455 



Crustacea 465 



Worms (Vermes) . . . 497 



Annelida 497 



Rotifera 500 



Turbellaria 502 



Helminthia 502 



Cestoiida 503 



Mollusca 504 



Mollusca, properly so called 504 

 Cephalopoda .... 507 



PAGE 



Gasteropoda 515 



Pteropoda 519 



Acephala 519 



Mollusco'ida 522 



Tunicata, properly so called 523 



Briozoaria 523 



Zoophytes 525 



Echinodermata .... 526 



Acalephae 528 



Polyps 530 



Infusoria 583 



Spongiaria 534 



The Geographical Distri- 

 bution of Animals . , 535 



