20. RAIID^E RAIA. 39 



46. T. occidental!* Storer. Cramp-finh; Torpedo; Numb-fish. 



First dorsal more than twice as large as second, placed over the ven- 

 trals; spiracles not fringed, their edges smooth; color almost uniform 

 black, with obscure darker spots ; beneath white ; length 2 to 5 feet ; 

 breadth of length, the disk very blunt or almost emarginate in front. 

 Atlantic coast ; not very common. 



(Storer, Am. Journ. Sci. Arts, 45, p. 165; Storer, Fishes Mass. 247.) 



47. T. caiifoi'llica. Ayres. California Cramp-fixli. 



Dark grayish brown above, thickly spotted with black ; disk broad 

 and rounded, forming more than half the entire length ; teeth small, 

 very sharp. Coast of California. (Ayren.) 



(Ayres, Proc. Cal. Ac. Nat. Sci. 1854, TO.) 



> 



SUPER-FAMILY RAIOIDEA. 



(The Trite Rays.) 

 FAMILY XX. RAILED . 



(The Skates.) 



Rays with the disk broad, rhombic, more or less ypinous or rough ; 

 tail stout, rather long, with a longitudinal fold 011 each side, the skin 

 commonly rough with spines ; usually two dorsal tins and sometimes a 

 caudal fin present on the tail; pectoral fins extending to the snout; 

 ventrals large ; no serrated spine, on the tail ; no electric organs ; ovi- 

 parous, the eggs being laid in large leathery egg-cases, four- angled, with 

 two long tubular " horns " at each end. Genera 4 or more ; species 40, most 

 of them belonging to the genus Raia. Skates of generally small size ; 

 found in all seas. 



* Caudal fin rudimentary or absent; pectorals not confluent around the snout ; ven- 

 trals deeply notched -. RAIA, 37. 



37. RAIA Linnajus, 1758. 

 Rays. 



(Artedi Liimaiiis, Syst. Nat. : type Raia clarata L.) 



This genus, as here understood, comprises all those Raiidw which have 

 the pectoral fins not continued around the snout, the ventrals deeply 

 notched, and the caudal fin little developed or wanting; tlie tail is very 

 distinct from the disk, and is provided with two rayed dorsal fins ; the 

 skin of the body is usually more or less spinous ; the dentition differs 

 in the two sexes, and the male is usually provided with a differentiated 

 patch of spines on each pectoral. Species numerous. 



