Contents. 



Preface V 



Introduction VH 



Polyzoa. 



1. Rhabdopleura mirabilis 1 



The Polyparium 3 



The Polypide 4 



The tentacular arms 6 



The bucal shield 8 



The contractile cord 10 



The axial cord 11 



Vital phenomena 12 



Occurrence 12 



Characteristics of genus and species 13 



Development 14 



Concluding remarks 15 



2. Flustra abyssicola 19 



Conchifera. 



3. Yoldia obtusa 23 



4. Pecchiolia abyssicola , 25 



Cephalophora. 



5. Dentalium agile 31 



6. Triopa incisa 35 



7. Gonieolis typica 37 



Annelida. 



8. Umbellisyllis fasciata 41 



9. Paramphinome pulchella 45 



Anthozoa. 



10. Mopsea borealis 50 



11. Fungiacyathus fragilis 58 



I* 



