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CONTENTS 



(5) Breathing by Lungs ; covered with Feathers ; Anterior 

 in the Form of Wings ; Oviparous. 



Limbs 



(c) Breathing by Lungs ; covered with Horny or Bony Shields ; 

 mostly Oviparous. 



(d) Breathing by Gills when Young, in Adult Life by Lungs and 

 Gills, or by Lungs alone ; Skin smooth and soft ; mostly Oviparous. 



Class IV. : Amphibians... 



Order I.: Frogs and Toads 

 „ II.: Tailed Amphibians 



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(e) Breathing by Gills throughout Life ; Skin usually bearing 

 Scales ; Limbs in the Form of Fins ; mostly Oviparous. 



Class V.: Fishes 



Order I.: Bony Fishes... 



„ II. : Enamel-Scaled Fishes 

 ,, III.: Sharks and Bays 

 ,, IV. : Round-Mouthed Fishes 

 „ V. : Lancelets 



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