22 CONTRIBUnONS TO NORTH AMERICAN ICHTHYOLOGY— IV. 



18.-CARCHARI]\US BlainTille, 1816. 



Blue Sharks. 



{Cipiocephalus Kleiu, Gill.) 

 (Carcharias Ciivier, not of Eafinesqxip.) 

 {Prionodon Miiller & Heiile.) 

 {Eulamia Gill.) 



(Blainville I'^lfi : type Carcharinwi comincrsoni Blainville.) 



Large sharks, withont 8i)ii'acles, with the teeth in both jaws strongly 

 serrated in the adult, those in the upper jaw broad, those below nar- 

 rower, straight, and claviform ; tirst dorsal large ; seeond dorsal much 

 smaller, usually not larger than the anal. Species numerous in the 

 tropical seas, {xdp/apo^, rough ; /i;vry, shark; abbreviated from Carclia- 

 rorhinus.) 



* Body and head slender; dorsiil tin inserted miflway between pectorals and veji- 

 trals (Carcharhtus). 



25. C. srlatlCUS (L.) Jor. & Gilb.— Gm(< Blue Shark. 



" Snout very long, nostrils rather nearer to the mouth than to the 

 extremity of the snout ; no labial fold except a groove at tlie angle of 

 the mouth ; teeth of the ui)per ja^v oblique, scarcely constricted near the 

 base ; lower teeth slender, triangular in young exami)les, lanceolate, with 

 a broad base, in old ones. Pectoral lin long, falciform, extending to the 

 dorsal, which is nearer the ventrals than the root of the pectorals." {Giin- 

 ther.) A large shark of the warm seas, occasionally taken on our 

 coast. 



{Sqaalus (jlaiicns L. Syst. Nat. ; Carcharian {jlaucus Gnnther, viii, 3()4.) 



**Body and head stout; dorsal fin placed close behind the root of the pectorals 

 (Evlamui Gill). 



26. C. obsciinis (Le Sueur) J. & d.—Diiski) Shark. 



Dark clear blue above, white below; head ratlier i)ointed, flattened 

 above and below ; lirst dorsal rather large ; second smaller than the 

 anal, and considerably produced behind ; jjectorals large, falciform. A 

 large shark, reaching a length of nine or ten feet, inhabiting the North 

 Atlantic and frequently taken on our coast. 



(Sqitaliis ohscurus Lc Sueur, .Jouni. Ac. Nat. Sci. Phila. 1818, i, ^U3 ; Carcharias 

 ohscitrus Giinther, viii, 3GG.) 



27. C milborti (-Miiller & Henle) Jor. &. Gilh.— i>7He Shark. 



This species is represented as having the snout shorter, blunter, and 



