FISHES OF MASSACHUSETTS. 29 



terior angle of eyes to occiput. At posterior angle of opercu- 

 lum j at same angle of preoperculum j the whole lower edge 

 of preopercle j the scapular bones ; all seem like sharp points 

 and edges concealed by the skin. The operculum is of a tri- 

 angular form, one inch in length, bony beneath skin, with its 

 posterior angle acute, united to the preoperculum by its ante- 

 rior superior angle by means of a membrane. Preoperculum 

 large ; its superior and posterior angles obvious to the touch ; 

 its lower edge sharp, and feeling as if it was divided into two 

 ridges. Eyes circular ; diameter of eye equal to half the dis- 

 tance between eyes. Nostrils tubular, situated on each side of 

 snout, just at the edge of the intermaxillary bones. Lips fleshy ; 

 jaws equal ; numerous minute teeth in jaws and upon pala- 

 tine bones mouth situated obliquely ; Lateral line straight, 

 looking like interrupted dots. 



The Dorsal fin arises on a line above the middle of the pec- 

 toral fins, and is continued to, and united with the caudal : 

 all its rays are spinous, strong, distinct, and concealed by a 

 common membrane : the first few rays are shortest. 



The Pectorals arise beneath the membrane of the branchiae, 

 as it is connected with the body : their length and half their 

 height rounded. 



The Anal fin arises upon the anterior half of body, and is 

 similar in its form and the character of its rays and their en- 

 veloping membrane, to the dorsal fin. 



The Caudal fin appears almost like the prolongation of the 

 dorsal and anal fins. It is rounded at its extremity. 



The fin rays are as follows : B. 7 ; D. 77 ; P. 13 ; A. 50 ; 

 C. 19. 



The flesh being removed from the smallest of the three 

 specimens above spoken of, the following appearances are pre- 

 sented. The longitudinal ridges upon top of head ; the sub- 

 orbitar, inferior maxillary and preopercular bones, with deep 

 excavations or cavities. The angles of gill-covers quite acute, 

 as also those of scapulae ; humeral spine very prominent. 

 A single row of teeth, in jaws j on sides, double, in front j those 





