THE TRIASSIC PERIOD 



697 



Fig. 473. A Group of Triassic Cephalopods. a, Trachyceras austriacum 



3 Mois.; b-c, Tropites subbullatus Hauer; d, Choristoceras marshi Hauer; 

 e-f, Ceratites nodosus de Haan, lateral and ventral views of the shell. 



