8H l.I'-T OF FISH. 



17*. Batis. — Caudal-fin distinct; pectoral-fin hardly produced 

 beyond the middle of the beak ; ventrals two-lobed ; beak none ; 

 tail with electric organs. 



II. Raidae anomalae. — Body gradually tapering to the tail. 



4. Torpedini. — Body orbicular, smooth; head rounded; tail de- 

 pressed ; moderately long. 



18. Temera. — Dorsals none ; body rounded ; spiracles near the 

 eyes ; mouth slender; internal labial-valves to both jaws. 



19. Asteape. — Dorsal one; body rounded; spiracles near the 

 eyes ; mouth slender ; internal labial-valves to both jaws. 



20. Narcine. — Dorsals two ; body roundish or angular ; spiracles 

 near the eyes; mouth slender; internal labial-valves in only one 

 jaw ; teeth extended beyond the edge of the lips. 



21. Torpedo. — Dorsals two ; body rounded, truncated in front ; 

 spiracles far from the eyes ; mouth larger. 



•">. Rhinobatina. — Body rhomboidal, elongated, beaked; tail thick, 

 fleshy ; dorsals two, far apart ; caudal apical. 



* Dorsals both opposite to the ventrals. 



22. Trygonorhina. — Body rhomboidal ; beak triangular ; caudal 

 obliquely truncated, one-lobed. 



23. Platyrhina. — Body orbicular ; beak scarcely produced; cau- 

 dal obliquely truncated, one-lobed ; nasal-valve elongate. 



24. Rhinobatus. — Body oval ; caudal obliquely truncated, one- 

 lobed ; nasal-valve scarcely produced. 



** Front dorsal opposite to the ventral. 



25. Rhynchobatus. — Body oval; caudal two-lobed; nasal- 

 valves scarcely produced to the inner angle ; mouth waved ; teeth 

 broad, elliptical. 



26. Rhina. — Body orbicular ; caudal two-lobed ; nasal-valves 

 produced to the inner angles ; mouth waved ; teeth rounded. 



6. Pristidini. — Body elongate, depressed in front ; beak very long, flat, 

 bony, spined on each side. 



27. Pristis. — Teeth granular ; gill-slits inferior. 



28. Pristidophorus. — Teeth acute ; gill-slits lateral ; nose with 

 free beards; eyebrows free. 



