'8 



PISCES 



CLASS I 



Lower 



more or less rounded, very deeply overlapping, and externally striated. 

 Carboniferous ; Scotland. 



Family -2. Platysomidae. Traquair. 



Trunk deeply fusiform or irregularly rhombic and laterally compressed. Head 

 hones enamelled; hyomandibular nearly vertical and mouth small; teeth, when 

 present, more or less blunt, chiefly on the pterygoid and splenial bones. Fins with 

 fulcra ; pelvic fins small or absent ; dorsal fin single, much extended. Scales rhombic, 

 deepened on the flank, each with an inner vertical keel projecting as a peg at the upper 

 border. Carboniferous and Permian. 



Eurynotus, Ag. (Plectrolepis, Ag.). Trunk deeply fusiform. Teeth short, 



obtusely conical to spher- 

 oidal. Pectoral fins 

 large ; dorsal fin arising 

 opposite the pelvic pair 

 and extending to the 

 caudal fin ; anal fin short- 

 based. E. erenatus, Ag., 

 from Lower Carbonifer- 

 ous, Scotland ; other 

 species from Ireland and 

 Belgium. 



Mesolepis, 

 Wardichthys, 

 Carboniferous ; 

 and England. 



Cheirodiis, 

 (Ampltieentrum, 

 (Fig. 140). Trunk deep, 

 rhombic. Pectoral fins 

 very small, pelvic fins absent, Dorsal and anal fins directly opposed, and both 



Fig. 140. 



Gheirvdus granulosus. Young sp. Coal Measures ; North Staffordshire. 

 Restored. Lettering as in Fig. 136 (after Traquair). 



Young ; 



Traquair. 



Scotland 



M'Coy 

 Young), 



A 



n 



Fig. 141. 



Platysomna striatus. Ag. Upper Permian (Magnesian Limestone); 

 Durham. 1/4 " at - S ' Z,J (restoration alter Traquair). 



Fig. 14-2. 



Platysomus parvulus, Ag. 

 Scale, outer (.4), ami innei 

 ( /.') aspects, twice nat. size. 

 Coal Measures ; England. 



much extended. Teeth absent, but pterygoid and splenial with denticulated 



