78 



PISCES 



CLASS I 



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

 Carboniferous ; Scotlarid. 



Lower 



Family 2. Platysomidae. Traquair. 



Trank deeply fusiform or irregularly rhombic and laterally compressed. Head 

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

 preserif, more or less hlunt, chiefly on tlie pterygoid and splenial hones. 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 vpper 

 border. Carboniferous and Permian. 



Eurynotus, Ag. (Pledrolepis, 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. F. crenatus, Ag., 

 from Lower Carbonifer- 

 ous, Scotland; other 

 species from Ireland and 

 Belgium. 



Mesolepis, Young; 

 Wardiclähys, Traquair. 

 Carboniferous ; Scotland 

 and England. 



Cheirodus, M'Coy 

 (Amphicentrum, Young), 

 (Fig. 140). Trunk deep, 

 rhombic. Pectoral fins 

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



Cheirodus granuiosus, Young sp. 

 Restored. Lettering 



Fi«. 140. 



Goal Measures ; North Staffordsliire. 

 in Fig. 13(5 (after Traquair). 



l'latyaormis striatus. Ag. 

 Durhain. 1/4 nat 



Fio. 141. 

 Upper Permian (Maguesian Liniestone) : 

 size (restoration alter Traquair). 



Fio. 142. 



Platysoiuas parvulus, Ag. 

 Scale, outer (J), and inner 

 (/.') a8])eets, twice nat. size. 

 Goal Measures ; England. 



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



