FISHES OF NEW YORK 31 



Body slender and little compressed; head flat, semicircular in 

 front, posterior margins of " hammer " short, free, the lateral 

 margins continuous with the anterior; first dorsal high, midway 

 between pectorals and ventrals; second dorsal much smaller, 

 produced behind, higher and shorter than anal; ventral and 

 caudal fins moderate; pectorals large; mouth small; teeth 

 small, very oblique, deeply notched on the outer margin, dead 

 one sixth of total length to tip of caudal, slightly longer than 

 wide. 



Color uniform ashy, whitish beneath. Length 5 feet. At- 

 lantic and Pacific oceans, occurring on our coast from Long 

 Island southward. 



Neither Mitchill nor DeKay mentions the shovelhead shark, 

 though both record the hammerhead. Prof. Baird found it a 

 common fish in Great Egg bay in 1854, but the species was not 

 seen there by the writer in 1887. 



14 Sphyrna zygaena (Linnaeus) 

 Hammerhead Sha i A- 



Squalus zygacna LINNAEUS, Syst Nat. ed. X, 234, 1758; MITCHILL, Trans. 



Lit. & Phil. Soc. N. Y. I, 482, 1815. 

 Zyyaena malleus DE KAY, X. Y. Fauna, Fishes, 362, pi. 64, fig. 204, 1842; 



STOBER. Hist. Fish. Mass. 262, pi. XXXVIII, fig. 3, 1867. 

 Splujrna zi/yacua JORDAN & GILBERT, Bull. 16, U. S. Nat. Mus. 26, 1883; 



JORDAN & EVERMANN. Bull. 47, U. S. Nat. Mus. 45, 1896; SMITH, Bull. 



U. S. F. C. XVII, 88, 1898. 



Body elongate, cylindric; head hammer-shaped, its width two 

 or three times its length; nostril near eye, prolonged into a 

 groove which runs along nearly the entire front margin of the 

 head; eye large, placed near the angle formed by the anterior 

 and lateral margins of the " hammer ", enabling the animal to 

 look above and beneath; three rows of white, hyaline teeth in 

 each jaw, those in upper jaw entire, acute, triangular, their tips 

 directed outward from the center, with a shoulder on the outer 

 side; in the center a few with shoulders on both sides; gill open- 

 ings short and small, the last smallest and placed over the pec- 

 toral base; first dorsal large, quadrilateral, slightly behind pec- 

 torals, higher than wide, deeply concave behind, and pointed 



