LIST OF ILLUSTRATIONS. 



1. Gregarina of the Earth 



worm, 44 



2. Morphology of Rhizopoda, 



3. Actinophrys sol, .... 



4. Morphology of Foramini- 



fera, 



5. Nummulites Icevigatus, 



6. Acanthometrina and Poly- 



cystina, 



7. Morphology of Radiolaria, 



8. Diagram of Spongilla, 



9. Morphology and reproduc- 



tion of Spongida, . . 



10. Morphology of Infusoria, 



11. Vaginicola, Stentor, and 



Vorticella, .... 



12. Morphology of Hydrozoa, 



13. Morphology of Corynida, 



14. Reproductive processes of 



Hydrozoa, .... 



15. Medusiform gonophore of 



Clytia, 



1 6. Tubiilaria indivisa, 



17. Sertularia pinnata and 



Campanularia neglecta, 



1 8. Morphology of Oceanic 



Hydrozoa, .... 



19. Physalia utrictdus and Vel- 



ella vulgaris, . . . 



20. Morphology of Medusidcz, 



2 1 . Group of naked-eyed Med- 



usa, 97 



22. Lucernaria auricula, . 



23. Development of Lucer- 



narida, 



24. Generative zooid of Chry- 



saora, 103 



25. Generative zooid of Rhi- 



zostoma, 



26. Morphology of Grapto- 



lites, 



27. Didymograpsus V-fractus, 



28. Diagram of Actinia, 



29. Actinia rosea and Arach- 



nactis albida, . . . 



PAGE 



Morphology of Corals, . 1 14 

 Sclerodermic and Sclero- 



basic Corals, . . . .116 

 Pennatula phosphor ea, . 121 

 Virgularia mirabilis, . .121 

 Pleurobrachia pileus, . .125 

 Morphology of Ctenophora, 126 

 Structure of Coral-reefs, 130 

 Morphology of Echinoidea, 140 

 Cidaris papillata, . . . 140 

 Larva of Echinus. Dia- 

 gram of Echinus, . .142 

 Cribella oculata, . . . .145 

 Ophiura texturata and 



Ophiocoma neglecta, . . 148 

 Rhizocrinus Lofotensis, . 1 50 

 Comatula rosacea, larva and 



adult, 151 



Echinosphcerites aurantium, 152 

 Thy one papillosa, . . .154 

 Morphology of Tceniada, . 162 



Trematoda, 165 



Morphology* of Turbel- 



laria, 1 66 



Echinorhynchus gigas, . 169 

 Anguillula aceti and Dory- 

 laimus stagnalis, 



170 

 174 



Hydatina senta and Meli- 



certa ringens, .... 

 Diagram of an Annulose 



animal, 177 



Syrinx midus, . . . .178 

 Diagrammatic section of 



an Annelide, . . . .179 

 Medicinal Leech, . . .181 

 Serpula contortuplicata and 



Spirorbis communis, . 184 



Nereis, 187 



Diagram of the somite of 



a Crustacean, . . .194 

 Morphology of Lobster, . 195 

 Larva and adult of Achthe- 



res percarum, . . .199 

 Locomotive young of Ba- 



lanus, 201 



