Classification of Animals 



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IX. Classification of Animals, 



METAZOA. 



SUBKINGDOMS AND CLASSES OF ANIMALS. 



A i v A / J Series Metazoa (many-celled) 

 Animal Kingdom ( 2 Series Protozoa (one-celled) 



1. Vertebrata (animals with back-bone) 



2. Arthropoda (animals with segmented body and 



jointed legs) 



3. Mollusca (soft body covered with mantle) 



4. Vermes (bilateral, with no legs) 

 Subkingdoms 5. Echinodermata (radiate, with leathery or spiny 



covering 



6. Ccelenterata (radiate, with tentacles and nettling 



cells 



7. Porifera (sponge-like animals) 



8. Protozoa (no true tissues, single cells) 



Si. Mammals (suckle the young) 

 2. Birds (feathered, wings, lungs) 

 3. Reptiles (lungs and scales) 

 I 4. Amphibians (gills and lungs) 

 [ 5. Fishes (permanent gills, fins) 



Classes of Arthro- 

 pods 



Classes of Mol- 

 lusks 



1. Insecta (six legs, distinct head, thorax, and 



abdomen) 



2. Arachnida (eight legs, head and thorax 



united) 



3. Myriapoda (many legs, body of distinct seg- 



ments) 

 . 4. Crustacea (more than eight legs, gills) 



' i. Cephalopoda (head with arms around the 



mouth) 



2. Gasteropoda (shell of one valve, tentacles) 

 3 Lamellibranchiata (shell of two valves) 



Classes of 

 Worms 



1. Annelides (worms with soft body of similar segments) 



2. Brachiopoda (worms with shells) 



3. Polyzoa (minute, composite worms) 



4. Rotifera (minute ciliated worms) 



5. Nematelminthes (thread-like, not jointed) 



6. Platyhelminthes (flatworms) 



