FISHES OF MASSACHUSETTS. 53 



lower jaw, twenty-two inches ; length of upper jaw or sword, 

 beyond the point of lower jaw, three feet five inches. Jaws 

 without teeth. Gill-covers silvery brown. Upper part of 

 sword, dark brown, almost black, having a dorsal ridge, within 

 which is a groove. Under portion of sword, lighter colored, 

 smooth, with a velvety feel. The two anterior feet of sword 

 have a bony, perfectly smooth edge. Widest portion of upper 

 jaw, five and a half inches ; jaw gradually terminates in a 

 point. Eyes very moveable in their orbits, three and a half 

 inches in diameter; distance between eyes, eight inches. 

 Branchiae composed of four pairs of large parallel laminae, and 

 one smaller one. 



The Dorsal fin commences nearly on a line with the pos- 

 terior edge of the operculum. It is strongly falciform ; twen- 

 ty-two inches high, eighteen inches long. But eighteen rays 

 are obvious ; the whole dorsal ridge between them and within 

 six inches of base of tail, destitute of fin rays ; and in their 

 place, a shallow groove the whole extent, supporting a slight 

 membranous elevation. Six inches in front of base of tail, a 

 small fin four inches high, one inch long, composed of three 

 rays, looking like the adipose fin of the " Salmonides," or the 

 finlets of many of the " Scombej'oides." 



The Pectoral fin, also, is falciform, eighteen inches high, 

 six inches long ; above, almost black ; beneath, color of abdo- 

 men. 



The Anal fin is, like the preceding, falciform ; sixteen inches 

 high, ten inches long. The extremity of this fin terminates on 

 a plane with the termination of dorsal, and is formed like that. 

 This small portion is three inches high, and one long. Fin, 

 color of the abdomen. 



At base of tail, a transverse furrow three inches long and 

 two thirds of an inch wide. On each side of base of tail, a 

 lateral carina three inches high, eight inches long, three 

 inches back of dorsal, extending three inches on the caudal fin. 



The Caudal fin deeply forked; twenty-nine inches high, 

 eight inches long, six inches high in its middle. 



The fin rays are as follows: D. 18-3; P. 15; A. 11-3; 

 C. 17. 



