FISHES OF MASSACHUSETTS. 99 



To Dr. Yale I am indebted for a fine specimen of this spe- 

 cies, taken at Holmes Hole, which enables me to offer the ac- 

 companying description. Length fifteen inches ; greatest 

 depth one inch. Above, of a light green color ; beneath, a 

 clear silvery white. Just above the base of the pectorals, a 

 deep blue band arises and passes in a straight line to the origin 

 of the dorsal fin. Length of the head, from the angle of the 

 jaws to the posterior portion of ihe operculum, one inch six 

 lines ; flattened above, compressed on the sides. Length of the 

 lower mandible, from the tip to the eyes, three inches five lines, 

 and fleshy at its tip ; three lines longer than the upper mandible ; 

 both mandibles armed with distant, very sharp, conical teeth, 

 between which are numerous others, very minute ; no teeth 

 upon the upper mandible, for the extent of two lines from its 

 extremity. Eyes circular, three lines in diameter ; pupils 

 black, irides silvery. Distance between the eyes about equal 

 to the diameter of the eyes. Gill-covers silvery ; at the pos- 

 terior edge of the preoperculum, a vertical blue band, about 

 four lines long. Immediately in front of the eyes, a triangular 

 space, in which are situated the nostrils. 



The lateral line arises at the inferior angle of the opercu- 

 lum, and passing gradually up to the posterior extremities of 

 the pectorals, assumes a straight line, which is continued to 

 the base of the caudal rays. 



The Dorsal fin is situated upon the posterior fourth of the 

 body ; transparent, greenish, falciform, high anteriorly, very 

 low posteriorly. 



The whitish Pectorals are directly back of, and upon a line 

 with, the posterior angle of the operculum ; their length to the 

 height of their longest rays, is as 2 to 8. 



The Ventrals, of the color of the abdomen, are placed back 

 of the middle of the body ; their length to their height is as 1 

 to 4. 



The Anal fin commences in front of the dorsal, and termi- 

 nates upon the same plane as that fin ; its longest rays are 

 longer than those of the dorsal. 



The Caudal fin is slightly truncated obliquely, the lower 

 portion being the longer. 



