CHAPTER II 



SKELETON OF UKODELA AND ANUKA SKIN COLOUU-CIIANGING 



MECHANISM POISON -(4LANDS SPINAL NERVES RESPIIiA- 



TORY ORGANS SUPPRESSION OF LUNGS URINO -GENITAL 



ORGANS FECUNDATION NURSING HABITS DEVELOPMENT 



AND :\IETAMORPHOSIS 



SKELPyrON OF THE UrODELA 



The vertebral column.— The ninnber of vertebrae is smallest in 

 the terrestrial, greatest in the entirely aquatic forms, and is excep- 

 tionally large in the eel-shaped Amphiunnt. In the following- 

 table the sacral verteln'a is included in those of the trunk. 



The vertebrae of tlie Urodela and those of the Apoda differ 

 from those of all the other Tetrapoda ^ by possessing no special 

 centra or bodies. That part wliich should correspond with the 

 centrum is formed either by the meeting and subsequent complete 

 (•o-ossitic;ition of the Iwo chief dorsal and ventral pairs of areualia 



' Cri'diicrs term f'oi- all Vertebrates liiglirr tluiii lislies. 



