TRIASSIC PERIOD. 



427 



Among Vertebrates, the Fishes were all Ganoids or Selachians. 

 The Amphibians comprised the gigantic Labyrinthodon, a scale-covered 

 animal, of a Batrachian form, the skull of which (Fig. 748) was over 



Figs. 748-752. 



Amphibians. —Figs. 748, Mastodonsaurus giganteus (XyL);749, tooth of same ; 750, Cheirothe- 

 rium ( x =-L) : 751, track of turtle ? True Reptiles. — Fig. 752, Telerpeton Elginense. 



two feet long, and the teeth (Fig. 749) three inches, — magnitude 

 enough for the Otozoum of the Connecticut valley. The tracks (Fig. 

 750) referred to a genus named Gheir other ium (because of a resem- 

 blance in form to the human hand) are supposed to be 

 those of a Labyrinthodon. 



True Reptiles were represented by Swimming Saurians 

 (Enaliosaurs) ; Rhynchosaurs, or Saurians with a beaked 

 turtle like mouth ; Belodonts, between Lacertians and 

 Crocodiles ; and true Lacertians. 



The species of Mammal, Microlesles antiquus Plien., 

 a tooth of which is represented in Fig. 753, was a marsupial, and 

 was closely related to that of North Carolina (p. 415). 



