The True Sharks 215 
ceous of England. Myliobatis dixoni is common in the Euro- 
pean Eocene, as is also Myliobatis toliapicus and Aétobatis 
Fie, 155.—Eagle-ray, Aétobatis narinari (Euphrasen). Cedar Keys, Fla, 
trregularis. Apocopodon seriacus is known from the Cretaceous 
of Brazil. 
Family Psammodontide. — The Psammodontide are known 
only from the teeth, large, flat, or rounded and finely dotted or 
roughened on the upper surface, as the name Psammodus (pappos, 
