394 HISTORY OF THE FISHES OF MASSACHUSETTS. 
that portion of the jaw next to the colored side are the smaller. The nostrils are 
directly in front of the eyes; the anterior is tubular. Between the eyes is a smooth 
ridge, covered by the common cuticle of the head as far back as the posterior 
angle of the orbit of the upper eye; from this point it becomes naked and rough, 
and is continued back to the superior angle of the operculum, where it is much 
larger than at any other point, terminating obtusely; between the extremity of this 
and the commencement of the lateral line is a smaller bony tubercle, apparently 
separated from the former. | 
The lateral line commences just back of the outer edie of the tubercle just re- 
ferred to, and continues nearly in a straight course to the posterior extremities of 
the caudal rays. 
The dorsal fin commences above the superior anterior angle of the upper eye, 
and gradually increases in the height of its rays towards its posterior half, the 
height of the longest rays being five times that of the first rays; this fin termi- 
nates at the base of the fleshy portion of the caudal fin, its last ray being of about 
the same height as the first ray. 
The central rays of the pectorals are bifid. 
The ventral rays do not extend to the anal. 
The anal fin is formed like the dorsal, and terminates on a line with it. The 
rays of this fin, as well as of the dorsal, are somewhat scaled. 
The caudal fin is slightly rounded when expanded. 
The fin rays are as follows: — D. 62. P. 9. V. 6. A. 41. C. 16. 
Length, eight inches. | 
Remarks. This species differs from the plana in the smoothness of its body ; 
in the situation of the eyes; in its less distorted mouth; in the bony ridge upon its 
head; in the much greater thickness of its body; in its ventral fins not reaching 
the anal fin; in its caudal rays. being almost destitute of scales; in there being 
scarcely any curve at the origin of the lateral line; in the number of the dorsal 
and anal fin-rays; and in the rays of the fins being stouter. : 
Besides these external differences between this species and the plana, the differ- 
ent form of the teeth in the jaws of the two species, the absence of teeth on the 
hyoid bone of the plana, the comparative lengths of their intestinal tubes, and the 
difference in form of the vocal appendices, are very striking. 
This is not a common species. It is taken in company with the plana, and is 
generally known as the Plaice. 
. Massachusetts, STORER. 
