British Reptiles and Amphibians 



seem to have appeared, as stated, in Permian times, but 

 they evidently reached their most powerful position in 

 the Jurassic period, which may be included in the 

 " Middle Ages " of geological time. Fossil remains of 

 reptiles of huge proportions have been found. In spite 

 of the fact that there are many existing species of 

 Amphibians in the world, and even more Reptiles, both 



FIG. 5. FOSSIL REMAINS OF AN OLD-WORLD AMPHIBIAN 

 (Labyrinthodon giganteum). 



a. Footprints ; l>, head j r, tooth. 



classes should be looked upon as " back numbers "; 

 they have lost their ancient supremacy ; numberless 

 forms have become extinct, and in point of size they are 

 now reduced to mean proportions. In the days of their 

 supremacy they were the terrors of the Animal World ; 

 now the dwarfed descendants tread the earth in fear, 

 trembling before the onslaught of the Mammals which 

 are supreme. 



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