8 



STORY OF THE AMPHIBIANS 



limbs are small and useless. The creature moves by 

 wriggling. (See Fig. 4.) 



Fig. 4. — Congo snake (Murcenopsis tridadyla). 



Tlie Csecilians have bands around the body, by 

 which they pull themselves through the ground. 



In the le2:o:ed forms the number of the toes varies. 



In the grasping hand of the frogs and tree-toads, 

 there is found the first thumb in nature. So perfect 

 is this that many tree- toads can suspend themselves 

 for some time by a single hand. These have soft 

 round pads on the ends of the digits, which enable 

 them to stick to smooth surfaces — the slipping being 

 prevented by moisture. The cricket-frog can, by the 

 mere adhesion of its moist underparts, climb up ver- 

 tical glass and remain there even when so turned that 

 its back is downward ; and one little salamander, hav- 

 ing neither pads nor claws, can so run on ceilings. 



Claws are very poorly developed in the amphibi- 



