AMPHIBIA. 253 



The " caducibranchiate " section of this order is characterised by 

 the fact that both pairs of limbs are always developed, and the 

 branchiae are never retained throughout life. The most familiar 

 examples are the Water-salamanders or Newts {Triton). The Newts 

 (fig. 182), are well known as inhabiting i)Ools in many regions, and 

 the young lead a strictly aquatic life. When the lungs are devel- 

 oped the external gills wholly disajopear ; and the respiration becomes 

 strictly aerial, though the animals still spend a great part of their 

 time in the water. The larva or young form is at iirat destitute of 

 limbs, and the fore-limbs are the first to be developed, the reverse 

 of this taking place in the Frogs. In accordance with their mode of 

 life, the tail is compi-essed and flattened, so as to form an efficient 



Fig. 182.— The Great Water-Newt (Jnton cristatm), male. (Aftei- Bell.) 



swimming apparatus. The Water-salamanders are all oviparoup, and 

 the young are like the tadpoles of the common Frog. 



The so-called Land-salamanders {Salamandra), in the strict sense 

 of the term, are essentially terrestrial animals, though commonly 

 frequenting water ; and they retain the larvie within the oviducts 

 for a longer or a shorter time after the emergence of the embryo 

 from (he egg. They are, therefore, ovo-vivijiarous or even viviparous. 

 The tail is rounded and cylindrical. A common form is the Spotted 

 Salamander of Europe, in which the larva^ have at first external gills ; 

 but in the Alpine Salamander of Southern Europe, the larvse are 

 not brought forth until the gills are .shed. 



Order III. ANijferRA. 



#^ 



This order is the highest of the Amphibia, and comprises the Frogs 

 and Toads. It is sometimes known by the name of Batrachia (Gr. 

 hatrachos, a frog), or Anoura (Gr. a, without ; oura, a tail), the latter' 

 name heing derived from the fact that the adults are "tailless." 



The tailless Amphibia are characterised by the fact that whilst the 

 larva possesses a tail, and is furnished with gills, the adult has no 

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