328 



ICHTHYOPSIDA. 



liind-legs are enormously developed and adapted for leaping, the 

 toes always webbed ; the toes of the fore-limbs are free. The 

 Common Frog (Sana temjwirma), which is our common species, 

 is found over nearly the whole of Europe, IsTorth Asia, North 

 Africa, and North America. The adults hibernate in all manner 

 of moist situations — especially in mud, in dykes, and pools — 

 until the spring, when they come forth and soon commence to 

 breed and to deposit the gelatinous spawn in large masses in the 

 water. The development and growth of the tadjiole have been 

 previously described. 



The Frog often wanders far from water, but they must have 

 a certain amount of damp to flourish. They are most beneficial 

 in gardens, feeding off all kinds of vermin, and should he 

 encouraged with the Toad. 



Amongst the Urodela we have in Britain two well-known 

 species, the Great Crested Newt [Triton cridatiis) and the 

 Common Newt (Lissotriton tceniatus). The "Water-Salamandere 

 or Tritons have a compressed fish-like tail, and breathe only by 



Fig. 168.— Male Crested Newt (Triton crUtatvs). (Nicholson.) 



lungs. The tongue is small and free, and the mouth is pro- 

 vided with two rows of teeth. There will be observed, if we 

 examine a crested newt, to be four toes only to each foot in front 

 and five on each foot behind. All water-newts produce ovip- 

 arously, and the males can be distinguished by having a large 

 dorsal crest on the bade and tail. This crest appears during the 



