APPENDIX 

 A Synopsis of the Animal Kingdom 



This synopsis is primarily for reference purposes. All of the major groups of 

 animals have been included. In many cases the classification is carried down 

 to orders, with one or more genera cited as examples. Some of the extinct groups 

 in the molluscs, arthropods, echinoderms and chordates have been included, all 

 others are omitted. Those included are preceded by a dagger (f). 



The phyla appear in the order given on the following key. 



Unicellular: Phylum 1. Protozoa. 

 Uncertain status: Phylum 2. Mesozoa. 

 Multicellular: The subkingdom Metazoa. 

 No nervous system: Phylum 3. Porijera. 

 Nervous system: All remaining phyla. 



Little or no mesoderm and radial symmetry: the radiate phyla. 

 Ciliary locomotion, colloblasts: Phylum 4. Clenophora. 

 Muscular locomotion, nematocysts: Phylum 5. Coelenterata. 

 Well developed mesoderm with nephridia. 



Mouth-anus as a single opening: Phylum 6. Platyhelminthes. 

 Mouth and anus separate openings. 



Pseudocoelom, no circulatory system. 



No asexual budding, poor powers of regeneration, never with 



ciliated tentacles: Phylum 7. Aschelminthes. 

 Asexual budding, good powers of regeneration, with a ring of 

 ciliated tentacles: Phylum 8. Entoprocto. 

 No coelom circulatory system present: Phylum 9. Nemertea. 

 Eucoelom, circulatory system usually present: Superphylum Eucoelo- 

 m.ata. 

 Protostomous and primarily schizocoelous. 



Reduced coelom and no segmentation: Phylum 10. Mollusca. 

 Well developed coelom, usually segmented at least as larvae: 

 Phylum 11. Annelida and the related phyla 12. Echi- 

 uroidea, 13. Sipunculoidea, and 14. Priapuloidea. 

 Reduced coelom and segmented: Phyla 15. Onycophora and 

 16. Arthropoda. 

 Minor phyla that are protostomous but not closely related to the 

 preceding: some are enterocoelous: The lophophore-bear- 

 ing phyla 17. Phoronida, 18. Brachiopoda, and 19. Bryozoa, 

 and the phylum 20. Chaetognatha. 

 Deuterostomous and primarily enterocoelous. 



Hydraulic coelom and secondary radial symmetry: Phylum 21. 



Echinodermata. 

 Hydraulic coelom and gill slits: Phylum 22, Hemichordata. 

 Gill pouches and notochord: Phylum 23. Chordata. 



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