TAILLESS BATRACHIANS. 375 



cially as in these particulars they differ so widely 

 from any other member of their class. But these 

 characters apply only to the adult animals ; in the 

 tadpole condition, an unscientific observer would 

 scarcely detect any difference between a Frog and a 

 Newt. 



The Frogs (Rana) are too well known to need description. The 

 energetic movements of the Common Frog (Rana temporaria) 

 command general admiration. The length of its leaps and its 

 vigorous action in swimming depend on the great development of 

 the hinder limbs. These animals feed on slugs and insects, which 

 they seize by means of their tongue, the arrangement of which is 

 very curious. When at rest the tongue is doubled back upon itself, 

 so that the tip is directed towards the throat in seizing a fly or 

 beetle it is launched forth like lightning, and as quickly retracted, 

 with the captive prey adhering to its extremity. The accompany- 

 ing figure of the skeleton of the Frog may be compared with that of 

 the Salamander on a previous page. It will be seen, with many 



FlG. 306. SKELETON OF FROG. 



points in common, to present important differences, particularly the 

 small number of joints in the spine, the great size of the pelvis, or 

 bony frame- work at the hinder part, and the enormous development 

 of the hinder limbs, The Frog has no trace of ribs, which in the 

 Newts do exist, though very small. 



Frogs are distinguishable from Toads by a row of teeth all round 

 the upper jaw. They feed only on living prey. In winter they bury 

 themselves in the mud, or in holes, and do not eat. 



The Tree Frogs (Hyla} do not differ much from ordinary Frogs, 

 except that the extremity of each of their toes is enlarged and 

 rounded into a sort of viscid pellet, or ball, that enables them to 

 adhere to objects upon which they climb, and to ascend trees. En- 

 dowed with great suppleness and agility, Tree-frogs travel very 



