TRIASSIC PERIOD. 



437 



different genera of Swimming Saurians (Enaliosaurs) of the Triassic, whose 

 remains occur mostly in the Muschelkalk of Europe, and especially at Luneville, 



Figs. 661-663. 



Reptiles. — Fig. 661, Skull of Labyrinthodon (Mastodonsaurus) giganteus (X i^); 661 o. 

 Tooth of same (X 3^); 662, Footprints of Chirotherium(X ^2); 663, Footprints of a turtle?. 



Bayreuth, and in Upper Silesia. They are distinguished from the Enaliosaurs of 

 the Jurassic by the extraordinarily large temporal, orbitary, and nasal openings 

 through the cranium, which leave little bone. The Nothosaurus mirabilis was 

 about seven feet long. The teeth were thin, long, and conical, three to five times 

 as long as broad, striated, slightly inflexed, and inserted in distinct cavities. 

 Placodus is another related genus. Two or three Plesiosaurs of the Lias (as 

 P. Haichinsii and P. costatus) occur in the bone-bed at the very top of the Trias, 



Figs. 663 A, 663 B. 



Fig. 663 A, Molar tooth of Microlestes antiquus, side-view ; A', view of crown of same 

 663 B, Myrmecobius fasciatus ( X J4 )• 



or base of the Lias, at Aust Cliff in England. Other Triassic Saurians are the 

 Belodon of von Meyer (Phytosanrus of J ager), a carnivorous, crocodile-like species, 



