128 HISTORY OF THE FISHES OF MASSACHUSETTS. 



tween, anterior, and posterior to the ejes, reddish. At the base of the dorsal fin on each 

 side is a narrow green ridge ; also a similar ridge just back of the eyes. Pupils black ; 

 irides silvery, with the exception of the upper middle portion, which is brown or cupre- 

 ous. The dorsal fin is reddish, with the bodies of the anterior rays silvery white. Pec- 

 torals with a slight tinge of red, greenish at their base beneath. Ventrals of a greenish 

 tinge. Anal brownish, margined with blue. Caudal reddish. 



Description. The length of this species is from eight to twelve inches ; the length of 

 the head is about one fourth the length of the entire fish ; the depth of the body across 

 from the base of the pectorals is equal to rather more than one third its length ; the 

 width of the body at the base of the tail is equal to one tenth its length. Body very 

 much compressed towards the back ; back gibbous, gradually curving towards the tail. 

 The eyes are large and circular. The jaws when closed are equal. In the back of the 

 jaws are two rows of blunt teeth ; those in front of the jaws are sharp and prominent. 

 The lips are large and loose. The nostrils are double ; the anterior is smaller and circu- 

 lar, the posterior larger and vertical. The head is destitute of scales. The preoperculum 

 and operculum are covered with scales. A large semicircular scale is observed at the 

 commencement of the lateral line ; between this scale and the outer angle of the naked 

 space at the posterior angle of the eye, a band of smaller scales than those of the body 

 passes obliquely upwards to the anterior portion of the dorsal ridge. The lateral line, 

 commencing back of the upper angle of the operculum, and passing obliquely up to a 

 point on a line with the fifth or sixth spine of the dorsal fin, curves with the body to the 

 base of the tail. 



The dorsal fin is received into a deep groove at its base ; when this fin is not erect, 

 the spines are scarcely visible, so completely do they shut into this groove. The third 

 spine is the longest ; from the extremities of the first three spines are suspended delicate 

 filaments. Just anterior to the dorsal fin is situated a strong horizontal spine, almost en- 

 tirely enveloped by the skin, which projects forwards. 



The pectoral fins commence on a line beneath the origin of the dorsal fin ; they are 

 one fourth the length of the body. 



The ventrals are just back of the pectorals; their second and third rays are the longest. 

 A large subsidiary scale exists at the anterior edge. 



The anal fin is shorter than the dorsal, and terminates on the same plane with that fin, 

 and like the dorsal is received into a groove at its base. 

 The caudal fin is quite deeply forked. 



The fin rays are as follows : — D. 12-12. P. 15. V. 6. A. 3- 11. C. 16f. 

 Length about a foot. 



