Analytical Synopsis of the Order of Squali. 379 



First family, Carciiari.is. 



I. Carcharias (1. Sub-genns Scoliodon ; 2. Sub-gemis Pbysodon 

 Valenc. ; 3. Sub-genus Aprioii ; 4. Sub-genus Ilypoprion ; 5. 

 Sub-genus Prionodon). II. Sphyrna Raf. 

 Second femily, Tri.enodontes. I. Triajnodon. 



Second sub-section. With a nictitating membrane and spiracles. 

 First family, Galei. 



I. Galeus Cuv. II. Galeocerdo. Ill, Loxodon. IV. Thalassorbi- 

 nus Valenc. 

 Second family, Scylliodontes. I. Triakis. 

 Third family, Musteli. I. Mustelus. 



Third sub-section. Without nictitating membrane ; with spiracles. 

 First family, Lamn^e. 



I. Lamna Cuv. II. Oxyrhina Agass. III. Carcharodon Smith. 

 IV. Selache Cuv. 

 Second family, Odontaspides. I. Odontaspis Agass. 

 Third family. Alopecia. I. Alopias Raf. 

 Fourth family, Cestraciontes. I. Cestracion Cuv. 

 Fifth fomily, Rhinodontes. I. Rhinodon Smith. 



III. section. Sharks with an anal and a single dorsal fin. 

 One family, Notidani. 



I. Hexanchus Raf. II. Heptanchus Raf. 



IV. section. Sharks without an anal fin. 

 First family, Spinaces. 



I. Acanthias Bonap. II. Spinax Bonap. III. Centrina Cuv. 

 IV, Centrophorus. V. Centroscyllium. 

 Second family, Scymni. 



I. Scymnus (1. Sub-genus Scymnus ; 2, Sub-genus Lsemargus). 

 II, Echinorhinus de Blainv, III. Pristiophorus. 

 Third famil)^, Squatin.^, I. Squatina Dum. 



The principal innovations in this arrangement of their pre- 

 vious one, are the transference of the genus Pristiiyhorus to the 

 sub-order of Squali and the family of Scymni, the subdivision 

 of the sharks with a nictitating membrane into five families, 

 the more positive circumscription of the families, and the crea- 

 tion of a distinct one for Rhinodon. The name of Odontasjpis 



