CHAPTER XLVI 

 ORDER OF TAILED AMPHIBIANS 



URODELA 



THE members of this Order are readily distinguished from 

 the preceding group by the possession of tails, which 

 they retain throughout their lives; by their gills, which most 

 of them retain permanently; by the absence of scales, and by 

 the fact that with very few exceptions they are strictly 

 aquatic. It is safe to say that any four-legged aquatic crea- 

 ture having a tail but no scales, is either a salamander, newt, 

 mud-puppy or siren. 



The Order U-ro-de'la is the. dividing line between the 

 finny, gill-breathing fishes, and the four-legged, lung-breath- 

 ing, land-going lizards. Strange to say, its members are most 

 abundant in the temperate regions of the earth, and except 

 in two or three small areas, are absent from the tropics. In 

 Australasia there are none, and in South America and Africa 

 there are none save in their extreme northern portions. 



Of all countries, the region embracing^the United States 

 and the southern provinces of Canada is by far the richest 

 in species belonging to this Order, the total number present 

 being 52. Mexico and Central America contribute 14 more, 

 all salamanders. In this total of 66 species 18 genera are 



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