552 



FISHES. 



unknown. Dinichthys : a gigantic fisli from tlie Devonian 

 of North America (estimated at from 15 to 18 feet in length), 



Fig. 135.— Dorsal surface of Ptericlithys, after Pander, d, Dorsal fin ; c. 

 pectoral member ; 2-10, liead-bucklers ; 11-13, dorsal bucklers. 



with the dermal covering very similar to that of Cocco- 



