PLATE XVI. 



Fig. 1. End view of Ceeatodds HiSLOPUHCS, ehowing the longitudinal fiurow along base of tooth. 



Fig. 2. Ceratodus Vieapa, shewing ditto. 



Fig. 4, Ceratodus Hunteeianus, ditto ditto. * 



Figs. 8, 6, 6, 7, 8. Fi'agments of bonea found with the teeth in same beds. 



