FISHES OF NEW YORK 39 



Massachusetts, which is not the case at present. In 1845 about 

 150 at least were captured in nets at Monhegan Me. during three 

 weeks of mackerel fishing. 



The fish was valued for its oil, of which 11^ gallons have been 

 taken from a single liver. 



This species feeds on many kinds of fish, but persistently fol- 

 lows the mackerel schools, and is generally known as the 



mackerel shark. At Provincetown it is called the blue shark. 



g 



Genus LAMNA Cuvier 



Body short, stout, the back considerably elevated; snout 

 prominent, pointed; teeth entire, pointed, triangular, with a 

 small basal cusp on each side, one or both cusps sometimes 

 wanting on some teeth in the young; gill openings wide, and all 

 of them in advance of the pectoral fin; first dorsal falcate, in- 

 serted over the axil of the pectoral; second dorsal and anal very 

 small, nearly opposite each other; pectorals falcate; caudal 

 peduncle strongly keeled on each side; deep pits at the root of 

 the caudal above and below; caudal lobes nearly equal in length. 

 Size large. 



18 Lamna cornubica (Gmelin) 



Porbeagle 



Squalus eornulicus GMELIN, L. Syst. Nat. I, 1497, 1788. 



Lamna cornubica GUNTHER, Cat. Fish. Brit. Mus. VIII, 389, 1870; JORDAN 



& GILBERT, Bull. 16, TJ. S. Nat. Mus. 30, 1883; BEAN, Bull. U. S. F. C. 



IX, 198, pi. LVII, 1891; JORDAN & EVERMANN, Bull. 47, U. S. Nat. Mus. 



49, pi. VI, fig. 22, 189(5. 



Body short, stout, fusiform, its greatest depth equaling nearly 

 one fifth of the total length including caudal, and slightly less 

 than the length of the head. The caudal lobes are nearly equal 

 in length, the upper as long as the head and exceeding depth of 

 body; caudal peduncle strongly keeled on each side; deep pits 

 at tho root of the caudal above and below. The snout is conical, 

 pointed, its length somewhat more than the width of the mouth. 

 Teeth entire, triangular, pointed, with a basal cusp on each side, 

 the cusp sometimes wanting in young, -ff- or -H on each side in 

 an individual about 3| feet long, the third tooth of the upper 



