Analytical Synopsis of the Order of Squali. 397 



C Month infenor ; body subcylindrical. 

 D, Caudal bent upwards, with basal lobe. Ginglymostomatoidse. 



DD. Caudal straight. 

 CC, Mouth subterminal ; body depressed. 

 BBB. Dorsal fin single ; first absent. 

 AA. Anal fin absent. 



B. First dorsal before ventrals. 



a. Dorsals, each armed in front with a spine. 



b. Dorsals unarmed. 

 Snout normally produced. 

 Snout saw-shaped. 



BB. First dorsal above ventrals. 



II. Pectoral fins produced forward at base and 

 correspondingly notched. 



Mouth subterminal, body depressed. 



Scylliorhinoidaj. 



Crossorhinoidse. 



Notidanoidae. 



Spinacoidae. 



Scymnoidse. 

 Pristiophoroidse. 

 Echinorhinoidfe. 



Rhin.e. 

 Rhinoidse. 



Suborder SQUATJ Gill, 1861. 

 Family KHINODONTOIDyE, Owen. 

 Genus Rhineodon (Shiith) Muller and Jlenle, 1838. 

 Rhinodon Muller and Ilenle. 



Type Rhineodon typicus A. Smith. 



Family LAMNOID^ Muller and Henle. 

 Synopsis. 

 Branchial apertures very large, nearly meeting under the 



throat. Teeth small. 

 Snout abruptly slender and conic. 

 Snout short and blunt. 

 Branchial apertures moderate. Teeth well developed. 

 Teeth compressed, triangular and serrated. 

 Teeth nail-shaped, long, flexuous, prismatic, and acute. 

 Dorsal nearly intermediate between pectoral and 

 ventrals. 



Cetorhinin.b. 



Polyprosopus. 



Cetorhinus. 



ISURIN.«. 



Carcharodon. 



Isnropsis, 



