662 GEOLOGICAL SURVEY OF NEW JERSEY. 



taring membrane ; spiracles behind and near eye ; first dorsal fin 

 large ; tail fin as long as body, with a pit at its root and a notch 

 near tip. 



ALOPIAS, Raf. 



(Squalus. Alopecias.) 



A. vulpes, Gmel. Thresher. Fox Shark. Swingle-tail. Long-tail 

 Sharks, &c. 



For characteristics, see family characters. 

 " This is a common species, frequently taken on hooks baited 

 for other fish." 



Family ODOXTASPID^. 



Sand Sharks. 



Mouth wide ; teeth large, long and narrow ; gill openings all in 

 front of pectorals ; dorsal fins nearly equal ; pectorals short ; no nicti- 

 tating membrane; spiracles pore-like. 



ODONTASPIS, Ag. 



(Carcharias.) 

 O. littoralis, Mitch, (americanus.) Sand Shark. Shovel-nose. 



Teeth awl-like ; no basal cusps on first and fourth upper teeth 

 and first lower ; body elongate ; head pointed ; fins small ; color 

 gray. Length, 4 to 6 feet. Voracious. 



" This species, described in full by the author, was taken off 

 Beesley's Point." [C. C. A.] 



Family LAMNIDJE. 



The Porbeagles. 



Size large ; body stout ; mouth wide ; teeth large ; lobes of tail fin 

 nearly equal ; first dorsal and pectorals large ; second dorsal and 

 anal very small ; spiracles minute or absent ; gill openings wide and 

 lateral. 



