172 THE STORY OP THE EARTH AND MAN. 



Still the Permian has some life features of its own, 

 and we must now turn to these. The first is the oc- 

 currence here, not only of the representatives of the 

 great Batrachians of the coal period, but of true rep- 

 tiles, acknowledged to be such by all naturalists. The 

 animals of the genus Frotorosaurus, found in rocks of 

 this age both in England and Germany, were highly- 

 organised lizards, having socketed teeth like those of 

 crocodiles, and well-developed limbs, with long tails, 

 perhaps adapted for swimming. They have, however, 

 biconcave vertebrae like the lizard-like animals of the 

 coal already mentioned, which, indeed, in their general 

 form and appearance, they must have very closely 

 resembled. The Protorosaurs were not of great size ; 

 but they must have been creatures of more stately gait 

 than theij" Carboniferous predecessors, and they serve 

 to connect them with the new and greater reptiles of 

 the next period. 



Another interesting feature of the Permian is its 

 flora, which, in so far as known, is closely related to 

 that of the coal period, though the species are regarded 

 as different; some of the forms, however, being so 

 similar as to be possibly identical. In a picture of the 

 Permian flora we should perhaps place in the fore- 

 ground the tree-ferns, which seem to have been very 

 abundant, and furnished with dense clusters of aerial 

 roots to enable them to withstand the storms of this 

 boisterous age. The tree-ferns, now so plentiful in the 

 southern hemisphere, should be regarded as one of the 

 permanent vegetable institutions of our world — those 



