J 



456 



MESOZOIC TIME — REPTILIAN AGE. 



saurus communis; fig. 709, head of same; figs. 710 a, 710 6, view and seetior 

 of vertebra; fig. 711, tooth of same, natural size. Fig. 712, Plesiosaurus dolicho- 



Fig. 707. 



Ganoid.— iEchmodus (Tetragonolepis) (X K); a > Scales of same. 



Fisrs. 708-714. 



Reptiles. — Fig. 708, Ichthyosaurus communis (X xio); 709, Head of same (X<fc); 710 a, 

 710 6, view and section of vertebra of same (X Vz)\ 711, Tooth of same, natural size; 712, 

 Plesiosaurus dolichodeirus (X a\>); 713 a, 713 b, view and section of vertebra of same; 714, 

 Mystriosaurus Tiedmanni. 



