THE PERMIAN PERIOD. 



205 



ent between the Permian and the overlying Triassic deposits. 

 Thus there are various deposits in different regions which 

 have yielded the remains of Reptiles, and which cannot in 

 the meanwhile be definitely referred either to the Permian 

 series or to the Trias by clear stratigraphical or palaeonto- 



Fig. l38.Protoro8aurus Speneri, Middle Permian, Thurlngla, reduced In size. 

 (After Von Meyer.) [Copied from Dana.] 



logical evidence. All that can be done in such cases is to be 

 guided by the characters of the Reptiles themselves, and to 

 judge by their affinities to remains from known Triassic or Per- 



