1906.] SELACIIIAX FISilES. 723 



Division 2. Galeoidei. 



Family 1. Odontaspiclidce. 



Odontaspis, Scapanorliynchus. 



Family 2. Lamnidce. 



Lamna, Carcharodon, Cetorhinus, 

 Alopias. 



Family 3. Orectolohidce. 



Parascyllium,Ginglymostoma,Rliinodon, 

 Orectolobus, Ohiloscyllium, Stegostoma. 



Family 4. S'cyliorJmiidce. 



Scyliorhinus, Pristiurus, Pseudotriacis. 



Family 5. Car char iidce. 



Oarcharias, Galeocerdo, Thalassorliiniis, 

 Galeus, TrijBnodon, Triacis, Mustelus, Sphyrna. 



Division 3. Squaloidei. 



Family 1. Cochliodontidce. 



Psephodus, Pleuroplax, Xystrodus, 

 Deltodus, Poe.cilodus, Cochliodus. 



Family 2. Hyhodontidce. 



a. E7jbodo7itince—Orodus, Oampodus, Sphenacan- 



thus, Tristychius, Hybodus, Acrodus, Astera- 

 canthus. 



b. Palceospinacince — Palseospinax, Synechodus. 



Family 3. Cestracioniidce. 

 Cestracion. 



Family 4, Squalidce. 



a. Squalince—CentYoscjllium, Echinorhinus, Oxy- 



notus, Etmopterus, Squalus, Scymnodon, 

 Centroscymnus, Centrophorus, Scymnorhinus, 

 Somniosus, Isistius, Euprotomicrus. 



b. Pristiophorince—'Pristio^'hoYiis, Pliotrema. 



Family 5. Sguatmidce. 

 Squatina. 



Suborder 2. HYPOTREMATA. 



Division 1. Narcobatoidei. 



Family 1. Torpedmidce. 



Torpedo. Karcine, HypnoSjNarce, Temera, 

 Discopyge. 



