GENERAL PREVIEW OF THE ANIMAL KINGDOM. 141 



Without notochord Invertebrata. 



Bilaterally symmetrical (chiefly). 

 Body made up of segments. 



Paired appendages jointed Phylum Arthropoda. 



Paired appendages unjointed Phylum Annulata. 



Body unsegmented; without paired appendages. 

 With mantle often secreting shell, 



Phylum Mollusca. 



No mantle Unsegmented Worms. 



Radially symmetrical in adult Phylum Echinodermata. 



Without true coelom. 



With a single mouth, which also- functions as an anus : stinging 



cells Phylum Caelenterata. 



With numerous incurrent openings or pores, and only one or 



few excurrent. No stinging cells Phylum Porifera. 



Single-celled animals (chiefly) Phylum Protozoa. 



